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The overall aim of this thesis is to develop empirical probabilistic frameworks that help to quantify the impacts of temporal and spatial scale dependencies and model uncertainties of climate projections regarding precipitation-dependent parameters. The thesis is structured in four articles. Article one is the first study that analyzed climate projections from the spatially highly resolved regional climate model (RCM) ensemble EURO-CORDEX. Additionally, the significance and the robustness of the projected changes are analyzed, and improvements related to the higher horizontal resolution of the new data set are discussed. A major finding is, that RCM simulations provide higher daily precipitation intensities, which are missing in the global climate model (GCM) simulations, and that they show a significantly different climate change of daily precipitation intensities with a smoother shift from low towards high intensities. The second article elaborates on impacts of temporal and spatial aggregation on extreme precipitation intensities. By combining radar data with cloud observations, the different temporal and spatial scaling behavior of stratiform and convective type precipitation events can be analyzed for the first time. The separation between convective and stratiform type events also allows to quantify the contribution of convective events to the extremes. Further, it is shown that temporal averaging has similar effects on the precipitation distribution as spatial averaging. Associated pairs of temporal and spatial resolutions that show comparable intensity distributions are identified. Using precipitation data from radar observations, a gauge station network and a spatially highly resolved regional climate model, the third paper optimizes the process that finds associated temporal and spatial scales (see second article). This information is used to develop a method that adjusts point measurements to the temporal and spatial scale of a previously defined model grid. The study shows that this procedure can be used to improve bias-adjustment methods in areas with a low gauge station density. It is known that the EURO-CORDEX ensemble overestimates precipitation and shows a common cold bias in the Alpine region. The fourth article evaluates how these biases are changing the temperature distribution and the temperature dependency of precipitation-frequencies. These biases are a source of uncertainty that is not captured by the robustness tests performed in the first article. A probabilistic-decomposition-framework is developed to quantify the impact of these biases on precipitation-frequency changes and to investigate causes for the ensemble spread.
In theory we pursue a sustainable development, but in reality we do not. An economy based on continuous growth, which evidently is not sustainable, is however the priority model almost everywhere. If we really aim at implementing sustainability, then we must radically change our economic model. Sufficiency - which calls for individuals mainly from so-called “developed countries” not to consume more than is really needed - may offer a useful alternative. We can still find some - last - examples of indigenous peoples living in a sufficient manner, all of them nowadays in those “developing countries”. We could learn at least from them that it is possible to live differently, i.e., in harmony with ourselves and our environment. This would pave the way for their - and for our all - protection, as well as the manner in which we understand at present development politics.
Loss of natural and semi-natural habitat due to increasing human land use for agriculture and housing has led to widespread declines in bee pollinator diversity and abundance, which raised global concerns about the stability of pollination services. Bee population dynamics depend on floral resource diversity and availability in the surrounding landscape, and loss of plant biodiversity may thus directly impair the fitness of individual bee species. However, whether and how plant and resource diversity and availability affect foraging patterns, resource intake, resource quantity and nutrient quality and ultimately fitness of generalist social bees remains unclear. In this thesis, we placed hives of the Australian eusocial stingless bee Tetragonula carbonaria (Apidae, Meliponini) in natural habitat (subtropical forests) and two landscapes differently altered by humans (suburban gardens and macadamia plantations), varying in plant species richness, resource abundance and respective habitat patch size. Foraging patterns and resource intake were compared between landscapes in different seasons and colony growth and fitness were monitored over two and a half years. Bee foraging activity, pollen and sugar intake, diversity of collected pollen and resin resources, resource quantity (colony food stores), colony fitness (brood volume, queenand worker reproduction) and colony growth overwhelmingly increased with plant species richness in the surrounding habitat. However, plant species richness and thus bee fitness was highest in gardens, not in natural forests, as bees in gardens benefited from the continuous floral resource availability of both natural and exotic plants across seasons. In contrast, foraging rates and success, forager orientation and consequently colony fitness was largely reduced in plantations. While bees maximized diversity of collected resources, collecting more diverse resources did however not increase resource functionality and nutritional quality, which appeared to be primarily driven by the surrounding plant community in our study. Conversely, individual worker fitness (body fat and size) was not affected by available resource diversity and abundance, showing that colonies seem not to increase the nutritional investment in single workers, but in overall worker population size. This thesis consequently revealed the outstanding role of plant biodiversity as a key driver of (social) bee fitness by providing more foraging resources, even when only small but florally diverse patches are available.
The dissertation deals with the impact of nitrogen deposition on the functioning of heathland ecosystems. Special interests were the displacement of heather (Calluna vulgaris) by the purple moor-grass (Molinia caerulea) as well as the fate of nitrogen loads in dry heathland ecosystems. The results of the studies undertaken in the field and in the greenhouse are presented as five individual journal articles. The nature of nutrient limitation was studied by means of fertilisation experiments with nitrogen (N) and phosphorus for heather and purple moor-grass (Articles I and II). The impact of nitrogen deposition on the outcome of competition between these two species was analysed during a competition experiment in the greenhouse (Article III). The aim of a 15N tracer experiment was to determine the fate of nitrogen deposition as well as allocation patterns (Article IV). In addition, the response of purple moor-grass to the combined effects of nitrogen deposition and summer droughts was investigated in a second greenhouse experiment (Article V). The fertilisation experiments showed that the growth of heather as well as of purple moor-grass is predominantly limited by N (Articles I and II). However, the results of the competition experiment demonstrated that only purple moor-grass has the ability to benefit from additional N loads, which in turn gives the grass the opportunity to displace heather (Article III). Drought treatment resulted in strikingly reduced biomass production of purple moor-grass in N-fertilised pots, mainly as a result of dying aboveground biomass during dry periods (Article V). This striking susceptibility of purple moor-grass to the combination of nitrogen deposition and drought must be taken into account, when predicting future developments of dry heathlands. The results of the 15N tracer experiment showed that the investigated heath is still in an early stage of N saturation, as indicated by a high immobilisation capacity and negligible leaching losses of 15N (Article IV). The findings of the dissertation contribute to a better understanding of the processes underlying the encroachment of purple moor-grass in dry heathlands and can enhance heathland management. The results can also be used to to evaluate the current and future status of this ecosystem particularly with regard to the various stages of N saturation as well as in the determination of “Critical Loads”.
The Model of Culture Fit explains the way in which socio-cultural environment influences internal work culture and human resource management practices. This model was tested using 1,954 employees from business organisations in 10 countries. Participants completed a 57-item questionnaire which measured managerial perceptions of four socio-cultural dimensions, six internal work culture dimensions and HRM practices in three areas ...
One of the Colombian strategies to diversify and decarbonize the energy sector is encouraging the use of non-conventional renewable resources (NCRR). This thesis measures the environmental rebound effect (ERE) when increasing the shares of wind power into the Colombian power grid in the residential (household) sector. For doing so, a process-based Life Cycle Assessment (P-LCA), an environmental extended input output (EEIO) model and re-spending models (almost ideal demand system AIDS) were applied. Direct rebound effect was measured thought the elasticity price of the electricity demand; furthermore, the environmental savings for increasing the shares of wind power into the grid were calculated via P-LCA. For doing so, a P-LCA for a wind farm in Colombia was performed, whereas the information for other energy resources (Hydro, Coal, Gas, Solar and Thermal) where collected from Ecoinvent 3.4 database. To calculate the environmental indirect rebound effect the monetary savings obtained for the environmental efficiency were calculated. For doing so, an AIDS was applied to obtain the marginal budget shares (MBS). Combining the MBS obtained with the EEIO model the monetary savings were translated into environmental indicators. The ERE is presented for ten impact categories (climate change (CC), acidification (A), ecotoxicity (E), marine eutrophication (MEUT), terrestrial eutrophication (TEUT), carcinogenic effects (CE), non-carcinogenic effects (NCE), ozone layer depletion (OD), photochemical ozone creation (POC), and respiratory effects, inorganics (RES)). Moreover, a sensitive analysis was conducted to measure the variability of the ERE to different values of the direct rebound effect and different percentages of price efficiency. The results show that the inclusion of the environmental rebound effect has generally a non-negligible impact on the overall environmental indicators across all studied years. Such impacts ranging across impact categories from 5% (eutrophication) and 6,109% (photochemical oxidant creation) for the combined model, whereas for the single model the values fall on the ranges of 1% (eutrophication) and 9,277% (photochemical oxidant creation). Further, a sensitivity analysis of the elasticity price of the electricity and the price of the electricity reveals that the ERE varies in different ways, specifically, changes in these parameters could vary the impacts, respectively, by up to about <1% and 38%. Backfire effects are present for 8 of the 10 environmental impacts studied in different magnitudes across the years, depending meanly of the savings available to re-invest.
The concept of empowerment has gained considerable attention in the field of international development. Institutions such as the World Bank and the United Nations invest considerable funds and efforts trying to facilitate empowerment in developing countries. Thus, empowerment becomes important when people need to take action and be innovative in overcoming scarcity and fighting against poverty. Research shows the positive effects of empowerment on entrepreneurship-related behavior and outcomes such as proactive behavior, goal achievement, and innovation. Yet, there is a dearth of research addressing the phenomenon of empowerment in entrepreneurship. This dissertation aims to contribute to the understanding of the role of empowerment in entrepreneurship and its effects. Particularly, this dissertation targets the interplay between empowerment and entrepreneurship in the context of developing countries. Chapter 1 provides a general overview of the different topics of this dissertation. Chapter 2, introduces the construct of psychological empowerment at work as the theoretical foundation to advocate for the importance of empowerment in entrepreneurship. The chapter takes initial steps in drawing the rationale and identifying empirical evidence for the relationship between empowerment and entrepreneurial behavior and outcomes. Specifically, the chapter links the components of psychological empowerment to concrete action characteristics in entrepreneurship such as effectuation and experimentation. Chapter 3 establishes a first empirical link between empowerment and entrepreneurship. The chapter provides the construct of entrepreneurial empowerment and develops a multidimensional measure to measure its dimensions. By means of a nomological network, the chapter reveals the relations of entrepreneurial empowerment with relevant constructs and outcomes derived from entrepreneurship and empowerment research such as innovation, self-reliance, and decision-making. Chapter 4 posits entrepreneurship training, particularly personal initiative training and business literacy training, as effective means to facilitate entrepreneurial empowerment and its effect on business performance. The chapter uncovers the mechanisms accounting for the relationship between entrepreneurship training and entrepreneurial empowerment. Chapter 5 provides general theoretical and practical contributions and finishes with a general conclusion.
This dissertation addresses the question of how sustainability curricula can be implemented and established in higher education institutions. Universities – as hubs for knowledge generation, innovation, and education – provide a central leverage point for sustainably developing society at large. Therefore, the institutionalization of sustainability curricula is not only socially demanded, but also stipulated in numerous political statements from the international community (e.g., those of the UN and UNESCO) and operationalized via Sustainable Development Goal No. 4: "Quality Education". Previous findings on how such implementation can be successful and what factors support or inhibit the process have come primarily through case studies of individual higher education institutions. These studies have been largely descriptive rather than analytical and leave open questions about the generalizability of their findings. The present dissertation addresses this research gap. Through a meta-study (i.e., an analytical comparison of existing case studies), generalizable findings on the implementation processes of sustainability curricula are explored. In the first step, a case universe was collected in order to provide a database for deeper analyses. In two further analysis steps that built on the case universe from Step 1, certain factors that promote or inhibit the implementation of sustainability curricula (Step 2) and specific implementation patterns (Step 3) were examined. The presented findings add a complementary empirical perspective to the discourse on the establishment of education for sustainable development (ESD) at higher education institutions. First, the case studies that specifically address the implementation processes of sustainability curricula are reviewed and analyzed here for the first time as part of a research landscape. This research landscape reveals where research on such implementation processes has been or is being conducted. On this basis, both researchers and funders can reflect on the status quo and plan further research or funding endeavors. Second, this dissertation offers the opportunity to compare a multitude of individual case studies and thus to develop new and generalizable insights into the implementation of sustainability curricula. The empirical analysis uses 133 case studies to identify key factors that promote or inhibit the implementation of sustainability curricula and to add a complementary perspective to the discourse, which has thus far been dominated by theoretical considerations and individual case studies. The analysis thereby offers a new perspective on generalizable influencing factors that appear to be important across different contexts. Thus far, specific patterns of implementation processes have been infrequently studied, and with few datasets. This dissertation analyzes the complex interplay between over 100 variables and provides one of the first research attempts at better understanding the processes that lead to the deep-rooted and comprehensive implementation of sustainability curricula. Internal and external practitioners of higher education institutions can find examples and evidence that can be useful in planning the next steps of their sustainability curriculum implementation. This dissertation offers generalizable empirical findings on how universities can succeed in recognizing their own responsibility to that end and in realizing this transformation through the implementation of ESD.
Companies increasingly use social and environmental accounting and reporting (SEAR) to measure, manage, and report their influence on ecological and social issues, i.e., climate change and human rights violations. Nowadays, there are many different tools, frameworks, and standards for SEAR that companies can use. Beyond the content presented in the tool itself, e.g., social and/or ecological information, these tools differ, among others, by the language used and the type of data collected (e.g., qualitative, quantitative, or monetary data). This dissertation aims to expand previous literature by clarifying the effects of SEAR on corporate decision-making and its influencing factors. Additionally, antecedents for implementation and use of SEAR in regard to supporting sustainability decision-making are discussed. For this purpose, the given dissertation investigates public sustainability reports by companies with different environmental orientation, conducts two survey-based case studies on the effects of different types of SEAR and one qualitative case study on the antecedents of institutionalizing management accounting change through SEAR. The results lead to seven criteria that practitioners and researchers should recognize for supporting successful SEAR regarding a company's environmental orientation, the role of employees and leadership as well as the specific SEAR tool itself.
When screening projects for potential investment placements, Venture Capitalists have to base their decision on the information provided in the business plan. The aim of this study is to make VCs aware of the influence of various factors which are discussed in business plans, such as the management team and risk minimising strategies. In order to do this, the business plans of four companies which received investment placements were analysed. The analysis revealed the two main success factors to be industrial experience and a filled product pipeline. The results also suggested that the business plan in its current form may not cover all the information needed for an optimal result. However, since this work is only a first approach further research needs to be carried out.
While it is a stylized fact that exporting firms pay higher wages than nonexporting firms, the direction of the link between exporting and wages is less clear. Using a rich set of German linked employer-employee panel data we follow over time plants that start to export. We show that the exporter wage premium does already exist in the years before firms start to export, and that it does not increase in the following years. Higher wages in exporting firms are thus due to self-selection of more productive, better paying firms into export markets; they are not caused by export activities.
The study empirically examines the long-term export behaviour of about 200 young technology-oriented companies from Germany and the UK. These firms were contacted by means of two surveys, in 1997 and 2003. In this study, three dimensions of firms’ international engagements are examined econometrically: foreign market entry and exit, degree of internationalisation (i.e., export-sales ratio), and the change of sales modes in international markets. Moreover, the causal relationship between a firm’s status of internationalisation and its performance (measured by the firm’s labour productivity as well as its employment and sales growth rates) is analysed.
Due to the financial markets disturbances of 2007/2008, a considerable number of financial intermediaries such as banks, credit institutions and asset management companies noticed substantial liquidity shortages, difficulties to refinance their operations as a result of a drying out of appropriate refinancing sources, and withdrawals of deposits by consumers. These turbulences in the financial markets forced governments and central banks to increase liquidity provisions to ensure a sufficient aggregate liquidity of the financial industry. Furthermore, policy-makers decided on bailouts of banks or on supporting financial intermediaries by governmental warranties or liquidity provisions to avoid a substantial number of insolvencies of banks and other financial institutions that may have rapidly deteriorated the global financial industry. In the aftermath of the crisis, politicians and economists discussed these decisions controversially because interventions by governments and central banks appear to have a deep impact on the global economy particularly in the financial industry. Moreover, legislative and regulatory authorities decided on increasing their vigilance, particularly with focus on principal-agent problems within certain sectors of the financial industry. A considerable amount of recent research papers has focused on the dynamics of liquidity shortages that suggest the recent crisis being related to both an increasing funding liquidity risk and an emerging market liquidity risk. Self-amplifying interdependencies appear to connect these two dimensions of liquidity risk that during the period 2007 to 2008 have led to the contagion effects in the global financial industry. Only little research work so far has provided evidence from the financial crisis in 2007/2008 while focusing on the German financial industry. Thus, my doctoral dissertation covers three research papers that address the occurrence of substantial liquidity risk and default probability within the German financial industry over the course of the financial crisis of 2007/2008. My first publication co-authored with Daniel Schmidt, Leuphana University of Lüneburg, entitled ‘Consumer reaction to tumbling funds - Evidence from retail fund outflows during the financial crisis 2007/2008’ focuses on funding liquidity risk of German retail funds. Contrary to the findings reported in some of the extant literature, our study indicates that over the past few years a change in investors’ behavior patterns means that investment decisions are made at short notice, and that shares are redeemed in a discriminatory manner when funds perform poorly. By using data assembled from 1672 retail funds in Germany over the period March 2008 to April 2010, we are able to show that in general, both the prior fund performance and prior net redemptions have a statistically significant influence on fund outflows. Moreover, there are indications that in recent crises situations that have resulted in the withdrawal of shares investors react fast to market signals. My second research paper entitled ‘Leveraging and risk-taking within the German banking system: Evidence from the financial crisis in 2007 and 2008’ examines the risk-taking attitudes of distinguishable German banking sectors. This study intends to examine whether the German banking system displays pro-cyclical behavior during 2000 to 2011, and to what extent specific sectors of the German banking system show significant balance sheet operations to increase their leverage during years of booming asset prices. The results of this study demonstrate that different sectors of the German banking system did operate their business more or less pro-cyclical. It also provides empirical evidence that certain banking sectors did favor refinancing their assets by short-term borrowing in the interbank market to increase their leverage during periods of extraordinary high returns in financial markets. Moreover, this study shows that banks, which operate above average leverages, tend to report a high volatility of return on assets and low distances-to-default. Finally, my third paper entitled ‘Are private banks the better banks? An insight into the ownership structure and risk-taking attitudes of German banks.’, and co-authored with Thomas Wein, Leuphana University of Lüneburg, tries to enlighten the influence of the different principal-agent relationships on the risk-taking attitudes of German banks. In this study, we propose our hypothesis that the distinguishable principal-agent relationships of German banks are significantly influencing the risk-taking attitudes of bank managers. Particularly, we intend to substantiate the theory that banks owned by dispersed shareholders or federal state authorities face a higher relevance of principal-agent problems than other banking sectors due to a missing ability to monitor bank managers. Our results underline that these problems appear to mislead bank managers showing an unreasonable risk-taking behavior. In a first stage, we rely on a theoretical model explaining that from the bank owners’ viewpoint three factors of the principal-agent relationships are determining the probability of choosing the optimal portfolio of risky assets. These factors cover the ability to control bank managers, the risk pooling capabilities of bank owners and bank managers, and the incentives of seeking high returns. To support our hypothesis we apply an empirical study to the distances-to-default of different German banking sectors. This demonstrates that risk-taking attitudes of banks are closely related to banks’ ownership. Consequently, our findings offer evidence, that legislative and regulatory authorities should increase their vigilance in terms of principal-agent problems within certain sectors of the banking industry.
Employee health is an important factor for individual and organizational performance. In particular the healthcare sector is characterized by high physical and mental demands that result in poor employee health and high levels of sick leave. One way to support employee health at the workplace is through leadership. By creating a healthy work environment and climate, leadership can promote employee health and well-being, in particular health-specific leadership. However, there has been scant insights into contextual factors that are relevant for health-specific leadership. This dissertation aims to investigate the relevance of contextual factors for health-specific leadership and its relationship with employee health. Three studies were conducted to identify relevant individual and work-related characteristics for health-specific leadership as well as to investigate the influence of specific individual and organizational factors. The first study is a questionnaire-based survey with 861 healthcare employees. Its findings show a positive relationship between health-specific leadership and employee health in the healthcare sector. Social demands and social resources are analysed as mediating factors. Furthermore, the affective commitment of employees is considered as an additional outcome of health-specific leadership. The second study identifies drivers and barriers for health-specific leadership in an explorative design based on 51 interviews with healthcare managers and collates these factors with the theoretical background. The findings show various influencing factors relating to leadership, employees, and the organization. The third study investigates the influence of individual factors on health-specific leadership and is based on a questionnaire survey among 525 healthcare employees. Managers personal initiative and employee self-care influence the relationship between health-specific leadership and employee burnout in different ways. In summary, this dissertation contributes to the literature by putting health-specific leadership into context and providing insights into influencing factors. The findings broaden the understanding of how health-specific leadership can influence employee health. The implications for theory and practice are discussed and directions for future research are outlined.
This paper analyzes, within a regional growth model, the impact of productive governmental policy and integration on the spatial distribution of economic activity. Integration is understood as enhancing territorial cooperation between the regions, and it describes the extent to which one region may benefit from the other region’s public input, e.g. the extent to which regional road networks are connected. Both integration and the characteristics of the public input crucially affect whether agglomeration arises and if so to which extent economic activity is concentrated: As a consequence of enhanced integration, agglomeration is less likely to arise and concentration will be lower. Relative congestion reinforces agglomeration, thereby increasing equilibrium concentration. Due to the congestion externalities, the market outcome ends up in suboptimally high concentration.
Traditional farming landscapes have been created in coexistence of rural dwellers and local ecosystems over long time spans, and can be considered tightly coupled ´social-ecological systems´ (SES). Since these landscapes typically embody exceptionally high levels of biological diversity and multiple socio-cultural values, their protection is critical from a sustainability perspective. Due to the pressures of globalization and social change, however, rural livelihoods and farmland biodiversity are at risk. While the focus of research is often on the Southern hemisphere, there are traditional farming landscapes in the former socialist countries of Central and Eastern Europe (CEE) which are equally affected by rapid change, and thus deserve particular attention. Since the institutional breakdown of socialism in 1989, the CEE states have not only been confronted with an unprecedented socio-economic and environmental transition. Their integration into the multi-level governance regime of the European Union (EU) further resulted in the transformation of decision-making structures and competition within the EU common market. In light of the profound changes traditional farming landscapes of Central and Eastern Europe are confronted with, they serve as a valuable source of learning about the institutional design necessary to harmonize socio-economic development and biodiversity conservation within regional social-ecological systems worldwide. This thesis is the result of an in-depth analysis of one traditional farming landscape of Central and Eastern Europe, namely Southern Transylvania (Romania). Based on empirical research involving diverse stakeholder groups, this thesis assessed the impact of EU policy on the area, the institutional features characterizing local-level governance in Southern Transylvania, and the barriers and bridges towards sustainable rural development. This thesis finds that while rural dwellers are highly dependent on smallholder farming and local ecosystems for their livelihoods, Southern Transylvania is currently confronted with a range of structural development barriers. These are likely to be exacerbated by a governance system consisting of historically grounded ´elite social networks´, and by EU policies which often do not fit rural realities. The findings of this dissertation underline that entrenched informal institutions, political will, and historical legacies play a critical role for the governance of traditional social-ecological systems since these ´social system features´ do not only mediate how external policies act on the local level. They may further restrict local adaptive and innovation capacities which, however, are critical for the transformation towards sustainable development. This thesis further finds that there are no blueprint solutions for the design of rural development strategies. Instead, (supra-) national policies should take better account of local socio-economic and cultural particularities.
A central aspect of sustainability governance is collaboration, which has been lauded for its benefits but also criticized for its challenges. The potential benefits of collaboration have apparently been recognized also in the context of EU agriculture. Yet, there has been a lack of holistic consideration of how collaboration can be systematically integrated and promoted in the governance of EU agriculture. Sustainable agriculture cannot only be encouraged through changes in the overall governance system but also through the support of existing and emerging small-scale collaborative initiatives for sustainable agriculture. Indeed, there has been substantial research on the conditions that influence success of similar collaborative initiatives. However, the knowledge resulting from this research remains rather scattered and does not allow for the identification of overall patterns. Additionally, little of this research specifically focuses on sustainable agriculture. What is more, the promotion of collaboration for sustainable agriculture is further complicated by the lack of clarity of the meaning of sustainable agriculture, which is an inherently ambiguous and contested concept. This cumulative dissertation aims to address these gaps by contributing to a better understanding of how collaboration can be facilitated and designed as a means to govern for and advance sustainable agriculture. For this purpose, the dissertation addresses three sub-aims: 1) Advancing the understanding of the concept of sustainable agriculture; 2) scrutinizing the current governance system regarding its potential to facilitate or hamper collaboration; 3) assessing conceptually and empirically how actor collaboration can be facilitated as a means to govern for sustainable agriculture, both from a top-down and a bottom-up perspective. In doing so, this dissertation focuses on EU agriculture and applies a mix of methods, ranging from qualitative to quantitative dominant. The findings of this dissertation highlight that collaboration has been underappreciated and even hampered as an approach to governing for sustainable agriculture. In contrast, this dissertation argues that collaboration offers one promising way to promoting and realizing agriculture and emphasizes the need to integrate different approaches to collaboration and to sustainable agriculture.
This thesis aims at contributing to the better understanding of the roles of international and domestic institutional and governance patterns for corporate sustainability practices. By combining governance and new institutionalism approaches it bridges the gap between the close look at specific corporate sustainability (CS) policies and the broader view on institutional frameworks. The qualitative comparative approach aims to provide deeper insights on the implementation of different governance schemes by transnational corporations ((TNC). Finally, the conclusions might allow for the development of a) recommendations for the balancing of TNCs' CS management between global and domestic requirements, and b) policy recommendations in the field of CS governance. The overarching research question is as follows: What role do national governance patterns play in comparison to global governance practices in shaping the corporate sustainability (CS) management of transnational corporations (TNCs)? In order to further operationalize this research objective, it is structured into three subquestions: (1) What are relevant institutional factors and global governance patterns for corporate sustainability/ Corporate Social Responsibility (CSR)? (2) What are relevant institutional factors and national governance patterns for corporate sustainability/CSR in Germany, the US, and India? (3) How do these national and global governance patterns influence TNCs' CS management? The first two questions aim at tracing the institutional framework and governance patterns at both national and international levels by identifying norms, stakeholder expectations, prevalent modes of governance and actors involved in governance processes. On this basis, the third question targets TNCs' reaction to internationally varying governance patterns. Here, it is of main interest how relevant governance instruments are perceived by business actors and to which extent their sustainability management at the companies' headquarters and subsidiaries reflect global and national institutional and governance patterns. In order to answer these questions, literature research and a structured qualitative analysis have been conducted. The concepts of CS and CSR build the basis to analyze how TNCs and their subsidiaries manage their social and ecological corporate responsibilities. Against this conceptual background, the research question is approached empirically by the means of an international comparison. Three institutionally highly diverse countries were chosen: Germany, India and the US. India, an emerging market economy, was included to increase the diversity of the sample and to close the research gap indicated above. In order to identify the differences in governance for CS in these three countries, document analyses and 42 guideline-based interviews with experts from governments, NGOs, trade unions and trade associations were carried out. At the same time, global governance instruments for corporate sustainability – which are already relatively well researched - were identified by analyzing the relevant secondary literature. In a second step, in order to explore how TNCs strategically deal with the multitude of different governance approaches at their headquarters and subsidiaries, three case studies of Germany-headquartered transnational corporations in the chemical and engineering industries (Siemens, BASF and Bayer) have been conducted.
Climate change and atmospheric deposition of nitrogen affect biodiversity patterns and functions of forest ecosystems worldwide. Many studies have quantified tree growth responses to single global change drivers, but less is known about the interaction effects of these drivers at the plant and ecosystem level. In the present study, the authors conducted a full-factorial greenhouse experiment to analyse single and combined effects of nitrogen fertilization (N treatment) and drought (D treatment) on 16 morphological and chemical response variables of one-year-old Fagus sylvatica seedlings originating from eight different seed families from the Cantabrian Mountains (NW Spain). Drought exerted the strongest effect on response variables, reflected by decreasing biomass production. However, D and N treatments interacted for some of the response variables, indicating that N fertilization has the potential to strengthen the negative effects of drought (with both antagonistic and amplifying interactions). For example, combined effects of N and D treatments caused a sevenfold increase of necrotic leaf biomass. The authors hypothesize that increasing drought sensitivity was mainly attributable to a significant reduction of the root biomass in combined N and D treatments, limiting the plants' capability to satisfy their water demands. Significant seed family effects and interactions of seed family with N and D treatments across response variables suggest a high within-population genetic variability. In conclusion, the findings indicated a high drought sensitivity of Cantabrian beech populations, but also interaction effects of N and D on growth responses of beech seedlings.
This paper presents the first nonparametric test whether German works councils go hand in hand with higher labor productivity or not. It distinguishes between establishments that are covered by collective bargaining or not. Results from a Kolmogorov-Smirnov test for first order stochastic dominance tend to indicate that pro-productive effects are found in firms with collective bargaining only. However, the significance level of the test statistic is higher than a usually applied critical level. This somewhat weak evidence casts doubts on the validity of results from recent parametric approaches using a regression framework that point to high positive effects of works councils on productivity.
The doctoral thesis deals with future challenges that the tourism market has to face on a global level. The problem is treated from different perspectives and with different thematic foci. Thematically, the thesis approaches both global changes in the tourism market and further developments of the research methodology. The methodological repertoire includes a Delphi survey in combination with a focus group, mobile ethnography in conjunction with participant observation and contextual interviews, and a quantitative online survey.
When Libet and colleagues published their results on the temporal order of movement preparation and the reported time of conscious will to move in 1983, they shed some doubt on the existence of free will. This marked the beginning of a controversial and still ongoing debate, not only about the existence of free will, but also about the appropriateness of methods and validity of results from research on free will. Belief in free will was also discovered as psychological research topic. Literature on belief in free will shows some evidence that most laypersons across different cultural backgrounds believe that they have free will and that a person's belief in free will might have an impact on cognition and behavior, tending to positive outcomes with a greater belief in free will. Empirical findings from the German-speaking area are sparse, probably due to a lack of validated measurements assessing belief in free will available in the German language. The aim of this dissertation is to critically examine some aspects in psychological research on free will and the belief in free will. Two studies are reported that aim to generalize the Libet paradigm for a free and voluntary decision with consequences for the acting person, as this was never reported to have been researched in literature before, and to test the critical objection that the measurement of reporting the conscious intention to move has a direct effect on the result in the Libet paradigm. Furthermore, the construction of the first inventory measuring belief in free will in the German language is described. This inventory was also created with the aim of overcoming some methodological problems in the existing instruments in English language. Furthermore, studies on the experimental manipulability of the belief in free will are reported. These findings provide implications in view of the current state of research on free will and belief in free will and its reliability.
Considering the historical relationship of subordination from the Global South countries to the Global North countries, this research aims to understand how culture is instrumentalized in the Peruvian political arena looking to achieve Western development standards. By focusing on the Commission of Culture and Heritage of the Congress of Peru, period 2016-2017, as its case study, it will do a discourse analysis to try to find the spheres in which developmental ideology is produced and reproduced. Those findings will be later discussed under decolonial thought and dependency theories.
In this framework the editor describes the intention, background and structure of the publication "Community Supported Economy - CSX - New entrepreneurial narratives in words, deeds, and pictures". In addition, this chapter introduces the readers to the concept of community-supported economy (CSX) and opens the space for their own reflection.
Fostering sustainable urban mobility at neighborhood-based mobility stations with cargo bikes
(2019)
Educational research has shown that reflection and feedback are crucial for substantial development of pre-service teachers' professional competence. However, reflection and feedback sessions are not a standard element of teaching practicums due to time- and location-constraints. Digital practicum environments can lift these constraints. Digital reflection and feedback environments have typically applied either textual accounts or video sequences of classroom practice, with varying effects. Consequently, the studies presented in this cumulative dissertation are focused on how the use of text- or video-based digital reflection and feedback environments during a practicum influence specific components of pre-service teachers' professional competence (i.e., beliefs about teaching and learning, self-efficacy, professional vision of classroom management, feedback competence). All studies followed a quasi-experimental, pre-test-post-test design. Pre-service teachers at the fourth-semester bachelor level in a German university took part in the studies. Pre-service teachers participated in a four-week teaching practicum at local schools. During the teaching practicum, pre-service teachers were divided into five different groups. The control group (CG) took part in a traditional practicum with live observations and face-to-face reflection and feedback with peers and experts. Pre-service teachers of the intervention groups (IG 1, IG 2, IG 3, IG 4) reflected and received feedback in highly structured text- or video-based digital environments. Intervention groups 1 (IG 1) and 2 (IG 2) participated in a text-based digital reflection and feedback environment. While IG 1 participants only received feedback from peers, IG 2 pre-service teachers also received expert feedback. Intervention groups 3 (IG 3) and 4 (IG 4) took part in a video-based digital reflection and feedback environment. IG 3 pre-service teachers only received peer feedback, whereas IG 4 participants also received expert feedback. Mixed methods were applied by generating quantitative and quantitative-qualitative data was with questionnaires, a standardized video-based test and content analysis. The studies demonstrated that classroom videos and video-based digital reflection and feedback environments can effectively enhance pre-service teachers' professional competence. This finding can be predominantly attributed to two characteristics of the application in the digital reflection and feedback environments: (a) being able to revisit a multitude of authentic teaching situations without time pressure and (b) the degree of decomposition by deliberate, focused practice and scaffolding elements. Furthermore, expert feedback seemed to be of better quality and entailed more substantial effects than peer feedback. The results of the conducted studies on professional vision of classroom management, beliefs about teaching and learning and feedback competence showed that expert feedback can be seen as a lens reducing and focusing classroom complexity, enabling pre-service teachers to perceive crucial teaching situations that would have otherwise gone unnoticed and to benefit from expert modelling of high-quality feedback. Consequently, video-based digital reflection and feedback environments with expert feedback can significantly improve pre-service teachers' professional competence during teaching practicums and, thus, better prepare pre-service teachers for future classroom challenges, leading to better learning environments for school students.
This PhD dissertation thesis aims to analyse and discuss how a company can interact with its supply chain stakeholders to facilitate the development of sustainable supply chains. The research is based on empirical and conceptual work and contributes to the field of corporate sustainability, supply chain management and its intersection. The thesis develops a conceptual framework to analyse four organisational spheres of interaction (inter, intra, supra and sub) in sustainable supply chain management (SSCM). Thereby, further insights into risk and opportunityoriented approaches of companies to SSCM are provided.
Increasingly, researchers are expected to work in collaborative interdisciplinary teams to tackle more complex and interrelated problems. However, the prospect of collaborating with others, from different disciplines, exerts countervailing forces on researchers. There is the lure of transcending the limitations of one's own knowledge, methods and conventions, belonging to diverse intellectual communities and tackling, together, ambitious research topics. On the other hand, there is the risk that collaborating across disciplinary boundaries will be taxing, confounding at times, with no guarantee of success. This thesis is about collaborative interdisciplinary research from the perspective of a formative accompanying researcher. The author accompanied an interdisciplinary research team in the field of sustainability over three years for the duration of a collaborative project. Formative accompanying research (FAR) is an approach to "research into research" that learns about, with and for a collaborative interdisciplinary team. The author found - through immersion in the literature, her own daily experiences of collaborating, and her observations – that interdisciplinary collaboration is very difficult. It requires a basic understanding and appreciation of other disciplines and methods, as well as the skills to integrate research inquiries and findings across diverse epistemologies. It also requires awareness that collaborative interdisciplinary research is more than an intellectual task of knowledge creation. Other factors matter, such as interpersonal relationships, power differentials, different research tempos and a sense of belonging. And these factors have an impact on processes and outcomes of collaborative knowledge creation. Knowing this implies a willingness to keep learning and to tolerate discomfort so as to cultivate deeper levels of collaborative capacity. The author discovered that in these deeper levels lie skills for staying with inevitable tensions, for talking and listening to generate new understanding together, and for applying a researcher's frank curiosity to oneself too. A formative accompanying researcher, who is part of the team she is researching, has to navigate delicate terrain. In this thesis, the author develops a FAR methodology that takes seriously the questions of positionality and relationality, and reflects on the experiences of putting these into practice. A FAR practice involves remaining in dynamic movement between observing and participating, between exercising curiosity and care, and between the researchers' own sense of impartiality and investment in relation to the issues at hand. There is merit in furthering the methodology and practice of FAR on its own terms. This includes attending to the skills required by a formative accompanying researcher to remain oriented within the concentric circles of research, relationship and loyalty that make up a collaborative team. There is also the question of how FAR, and other forms of research into research, can help to advance collaborative interdisciplinary research. The author argues for creating the conditions in research teams that would enable treating collaboration as a capacity to develop, and that would facilitate team members' receptivity to learning with FAR. Furthermore, she explores dilemmas of intervening as a formative accompanying researcher and of sustaining dynamic positionality over the long-term.
Global environmental changes and the subsequent biodiversity loss has raised concerns over the consequences for the functioning of ecosystems and human well-being. This thesis provides new mechanistic insights into the role of tree diversity in regulating forest productivity and forests’ responses to climate change. The thesis also addresses the overlooked functional role of ecological continuity in mediating ecosystem processes in the context of multiple global environmental changes. The findings of the thesis emphasize the need to retain the functional integrity of forest ecosystem by preserving biodiversity and acknowledging the ecological memory forests.
The future of forests is closely linked to climate change and energy transition because the preconditions for forest management are changed through climate and energy policies (Beland Lindahl and Westholm 2012). Forest management has multiple objectives, and different stakeholders have competing interests in forests. A strong dichotomy between environmental and economic interests has characterized forest policy and most conflicts about forests in the past (Winkel and Sotirow 2011). Climate change and energy transition modify this established conflict line because new conflicts related to climate mitigation, climate adaptation, and renewable energies have blurred the clear opposition between environmental and economic interest (Mautz 2010). In the context of the new challenges of climate change and energy transition, the need for effective, efficient and legitimate forest governance is gaining a new importance. Based on 86 qualitative interviews about forest conflicts and forest governance in five qualitative case studies, theoretical approaches focusing on multi-level and multi-scale governance are merged with the field of environmental and natural resource conflict research in this thesis. Forest conflicts and their governance are a multi-level and multi-scale issue. However, not so much is known about how collective and individual state and non-state actors act in complex governance systems and how they perceive governance systems. In order to contribute to the understanding of these knowledge gaps, this thesis tests the applicability of three theoretical perspectives on multiple scales and levels of decision-making (multi-level governance, polycentricity, politics of scale) to fruitfully study forest conflicts. Furthermore, the thesis provides empirical insights about forest conflicts in the face of energy transition and climate change. Based on the theoretical and empirical findings, this thesis provides practical recommendations to policy makers and practitioners on how to improve governance in forestry and the management of other natural resources. For example, this thesis shows the importance of considering different actor constellations in participatory processes at different governance levels, and that not every actor will react the same way to a certain method of decision-making. Furthermore, this thesis illustrates how trust building measures, such as enhanced communication between stakeholders, transparency in decision-making and forest education can reduce the risk of destructive conflict escalation. This thesis also demonstrates that energy transition and the discussion about climate change are sources of new conflicts, can change old conflicts, and add new, additional levels to forest governance. Thus, climate change and energy transition cause further fragmentation of forest governance and make forest governance more multi-level, create additional venue-shopping opportunities, and bring new actors into forest governance, causing new power constellations in the policy field. Forest governance is in a reconfiguration process which can be conceptualized as shift towards multi-level governance. Level choice and the relation of state and non-state actors in decision-making are important aspects of governance, thus the theoretical approach has yielded valuable insights in forest conflicts and the importance of scale construction in conflict discourses can be illustrated. Different levels are associated with different functions, strengths, and weaknesses of stakeholders; the perceptions of appropriate scale choice are often based on frames. The empirical findings have shown that level choice is often a normative and/or cultural decision, often no objective ´best´ decision-making level exists. Some actors consider different competing, overlapping, and nested decision-making levels to be an opportunity for interest realization; others feel helpless and overwhelmed in complex, multi-level systems. Different re-scaling strategies (up-scaling, down-scaling, fit re-scaling) are applied by actors to realize their interests. Non-state actors have an important function in linking processes from different levels. However, multi-level governance and related concepts have their limits for the explanation of forest conflict processes because some important factors cannot be captured with this approach. For example, social-psychological factors and conflict frames are important for the understanding of conflict development and governance and at a local level individual action and the relations between individuals crucially set the preconditions for the governance of conflicts.
This cumulative dissertation investigates food policy councils (FPCs) as potential levers for sustainability transformation. The four research papers included here on this recent phenomenon in Germany present new insights regarding the process of FPCs' emergence (Emergence paper), the legal conditions which affect their establishment (Legal paper), the different roles of FPCs in policy-making processes (Roles paper) and FPCs' potential to democratise the food system (Food democracy paper). Drawing on and contextualizing the results of the four individual studies, the framework paper uses the leverage points concept originally developed by Meadows (1999) and adopted by Abson et al. (2016) as a lens to discuss FPCs’ potential as levers for sustainability transformation. This conceptual background includes three so-called realms of leverage, which are considered to be of particular importance in transformational, solution-oriented sustainability science: first, the change, stability and learning in institutions (re-structure), second, the interactions between people and nature (re-connect) and third, the ways in which knowledge is produced and used (re-think). Framing the findings of the four research papers in terms of these three realms, the framework paper shows that FPCs could serve as cross realm levers, i.e. as interventions that simultaneously address knowledge production, institutional reform and human-nature interactions.
Financial Decisions in Family Firms. Private Equity Investors, Capital Structures and Firm Identity
(2017)
This paper-based dissertation deals with financial issues of family businesses. These businesses are mainly characterized by the overlapping of the two social systems: family and business. Thus, the involvement of an owner family can have a significant impact on corporate decision-making, for instance in terms of corporate finance decisions. In Germany, the latter is dominated by a strong orientation towards banks. Nevertheless, the relevance of external equity, as source of funding, has increased during the last years due to regulatory interventions (Basel III) and a growing number of alternative private equity providers. Against this backdrop, the present dissertation and its four papers examine different research questions in the context of capital structure decisions of family firms. These decisions are related to external equity as well as debt financing. The first paper is a structured literature review concerning the interaction of family firms and external equity investors. The paper analyzes the current state of knowledge and points out directions for future research, which is particularly relevant for a young and recently growing field of research. The second paper is a conceptual paper that deals with the differences of various types of private equity investors from the perspective of family firms looking for funding. The literature review paper revealed that existing studies so far neglected the topic of heterogeneity among investor types. Thus, the second paper represents a first attempt to close this research gap. Paper three also takes up a research gap identified by the first paper and examines the exit of private equity minority investments in family-owned businesses. The paper applies a qualitative empirical research design, which includes fourteen cases and related six interviews. The results reveal that the disinvestment phase of private equity investors only rarely leads to conflicts with owner families. The fourth paper uses a quantitative research design with a comprehensive dataset of 691 companies. The paper aims to compare the capital structures of large family and non-family firms. Overall, the findings show that family firms have significantly higher overall and long-term debt levels compared to their non-family counterparts. The identity as a family firm, which leads to a leap of faith by banks, can be a possible explanation for these results.
The principle of this thesis was to study the environmental fate of three highly used psychotropic drugs and this achieved through: 1) examining the biodegradability of TMI, DMI and CPTX, 2) studying the behaviour of TMP, DMI and CPTX in photodegradation tests using Xe and UV lamps with studying the effect of different environmental conditions on their UV-photodegradation behaviour, 3) monitoring the primary elimination of TMP, DMI and CPTX during photodegradation and biodegradation tests using HPLC, and measuring their degree of mineralization by means of dissolved organic carbon analyser (DOC), 4) elucidating the structures of the transformation products (TPs) which formed during the degradation of TMI, DMI and CPTX by using LC-MS/MS analysis, 5) analysing the biodegradability of their TPs by laboratory tests and in-silico assessments in order to determine the fate and persistence of these TPs in the aquatic environment, 6) conducting in-silico toxicity predictions for the selected psychotropic drugs and their TPs in human (carcinogenicity, genotoxicity and mutagenicity) and in eco-system (toxicity to microorganisms and toxicity in rainbow trouts). As an overall conclusion, the present work demonstrates that a combination of laboratory simulation tests, LC-MS/MS analysis and in-silico tools result in valuable new information regarding environmental fate of three important psychotropic drugs and their TPs. This dissertation also highlights that different environmental conditions such as temperature, initial drug concentration and pH can differently affect the degradation behaviour of pharmaceuticals even when they are highly structurally related. Therefore, one cannot conclude from one pharmaceutical to another but each one needs to be investigated individually and this present a great challenge for risk assessment kinetics of chemicals in the aquatic environment. The results presented here showed that the investigated pharmaceuticals and their TPs can negatively affect the environment which may be harmful to the ecosystem as they might have been present for decades in the aquatic environment without any knowledge of their environmental fate or connected risk. Therefore, further work needs to be done including analysis of environmental samples (e.g., surface waters), as well as laboratory toxicity tests to further expand knowledge on their exact environmental impact.
Uranine (sodium fluorescein, UR) has been routinely used in hydrological research to monitor surface and subsurface water flow, transport and mixing processes since the end of nineteenth century. Based on such obtained data, further conclusions can be drawn on the spread and behavior of pollutants (partly on models). Use of UR for qualitative (visual) studies of underground contamination is common, however data available on its environmental behavior (e.g., conversion, degradation or formation and fate of the transformation products, TPs) are incomplete or not readily comparable. UR observations of biodegradation are still speculative. S-metolachlor (SM) is a popular worldwide chloroacetamide herbicide, which highly correspond to the global pesticide use. It is offered on the French market as an effective multicrop herbicide against annual grasses and certain broadleaf weeds under the trade name Mercantor Gold (MG). Photodegradation contributes to the fate of SM in the aquatic environment. TPs were already found in surface and groundwater. However, further fate and assessment of the TPs was not done. Moreover, adjuvants in MG´s formula can affect the solubility, biodegradation, photolysis and sorption properties of the active compound SM. TPs can have different properties (e.g. more mobile, toxic or present at higher concentrations) that enable them to reach the environmental compartments not affected by the parent compound (PC) itself. To assess the ecological impact of pesticides, tracers, and their respective TPs on water organisms, their behavior can be investigated in laboratory screening biodegradation tests. Yet, incomplete data was available on SM, MG and UR transformation or their photo- TPs´ fate in surface and water-sediment systems. The combination of photolysis with aerobic biodegradation in order to identify persistent photo-TPs could provide new insight into the environmental behavior of the selected compounds. Therefore, principle of this thesis was to 1) identify the impact of MG´s adjuvants on the biodegradation, photolysis (Xe lamp) and sorption compared to the SM alone, 2) examine the photolysis and biodegradability of UR 3) monitor the primary elimination (photolysis) of the PCs by HPLC (-UV, -FLD) and measure the degree of mineralization by means of nonpurgeable organic carbon (NPOC) 4) elucidate the photo-TPs of SM, MG and UR by using LCMS/ MS 5) analyze biodegradability of the photo-TPs in order to determine their fate and persistence in aquatic environment 6) conduct in silico toxicity predictions (pesticides) in human (carcinogenicity, genotoxicity and mutagenicity) and eco-toxicity (microtoxicity, bioconcentration factor and toxicity in rainbow trouts). SM, MG and UR were found not readily biodegradable in Closed Bottle test (CBT), Manometric Respiratory test (MRT) and in water-sediment test (WST). Chemical analysis of photolysis samples showed higher elimination of SM in MG compared to SM alone whereas UR displayed high primary elimination rate in general. The overall low degree of mineralization indicated that abundant photo-TPs were formed. Furthermore, the photo-TPs were found not biodegradable in performed biodegradation tests. Only small degradation rates for UR could be observed in the CBT and WST. Additionally, in the MRT and WST new bio-TPs were generated from the photo-TPs of SM and SM in MG. Obtained results suggest that the MG formulation did not significantly affect the biodegradation, however it influenced the diffusion of the active substance (SM) to sediment and potentially affected the photolysis efficiency, which might result in faster formation of photo-TPs in the environment. In silico predictions showed that for many endpoints, biotransformation might lead to an increased toxicity in humans and to water organisms compared with the parent compound SM. No indications were found for UR toxicity. Still, target-oriented investigations on long term impacts of photo-TPs from UR are warranted. The present work demonstrates that a combination of laboratory tests, analytical analysis and in silico tools result in valuable information regarding environmental fate of the TPs from selected compounds. Furthermore, it was shown that photo-TPs formed in the aquatic environment should be taken into account not only the parent compound and its decay.
The global coffee market is connected to many sustainability issues like the persisting poverty of coffee farmers, and degrading ecosystems. Many interventions, from state-led regulation to industry-led certification processes, exist, that try to change global value chains to shift societies back on more sustainable trajectories. To this date, it is still under debate if these interventions are an effective means to change global value chains. With climate change and persisting issues of social justice as strong accelerators, calls are increasingly made for a radical transformation of global production and consumption patterns. Many frameworks try to inform research and real-world policies for a transformation of global value chains. In this dissertation, the author uses the framework of the practical, political and personal sphere proposed by O'Brien and Sygna (2013) highlighting that the interactions between these three spheres bare the greatest potential for a transformation towards sustainability. However, in this dissertation, the author argues that it is exactly at the nexus between the three spheres of transformation where barriers towards a fundamental shift of systems occur. He, therefore, uses three perspectives to bring empirical nuance to the problems that arise on the interplay between the different spheres of transformation. (1) The scientific perspective: using a systematic review of alternative trade arrangements; (2) the producer perspective: facilitating a participatory network analysis of social-ecological challenges of Ugandan coffee farmers and their adaptive management practices; (3) the consumer perspective: through the use of a German consumer survey and a structural equation model to investigate into the Knowledge-Doing-Gap end-consumers are facing. Through the results from the scientific perspective, the author is able to show that most of the research is investigating the certified market and that the effectiveness of labels rarely exceeding the practical sphere. His empirical research on the producer perspective highlights that Ugandan coffee farmers facilitate a variety of on-farm crop management (practical sphere) but their support structures rarely exceed informal exchange with neighboring communities (political sphere). Exchange with governmental actors and global traders is happening but has been assessed as not sufficient to cope with the social-ecological challenges the producers are facing. Through the results of the consumer perspective, the author is able to highlight that even though end-consumers have pro-sustainable attitudes (personal sphere) they are facing situational constraints (political sphere) that create a gap between their attitudes and the respective behavior. Using these empirical insights about drivers and barriers for a transformation he proposes that frameworks, aiming to inform research and policies, need to include two aspects: (1) the notion of a forced transformation; and (2) the translational capacity of the frameworks to create meaningful interdisciplinary discourses in different contexts. The author, therefore, propose two approaches:(1) a fourth sphere, called the "planetary force" to include the notion of a forced transformation that is already happening in different contexts, highlighted by the producer perspective in this dissertation; and (2) the consequent use of methods that create interdisciplinary exchange and rigorous testing.
To be prepared for one´s own career is a major task during career development. However, existing research has primarily focused on adolescence in the transition from school to work while research on career preparation among university students, that are challenged by successfully transiting from university to work, are lacking so far. Thus, this cumulative dissertation studies career preparation in terms of career decidedness, planning, confidence, and career engagement using large samples of German university students and alumni as well as a variety of quantitative methods like latent state-trait analysis, cross-lagged analysis, and mediation analysis with multiple mediators. In the first paper, the stable component of career indecision is investigated with longitudinal data stemming from two samples with different time lags (Sample 1: N = 363, 7 weeks; Sample 2: N = 591, 6 months). Furthermore, the combined and unique effects of career indecisiveness and generalized indecisiveness on life satisfaction are examined using a sample consisting of 469 university students. Results indicate that career indecision is determined by a stable component (i.e., trait career indecisiveness) that is associated with lower core self-evaluations, lower occupational self-efficacy, and higher perception of career barriers. Additionally, results indicate that the stable career indecision component explains 5% of the variance in student life satisfaction beyond self-evaluated generalized indecisiveness. The second paper deals with the relationships of vocational interest characteristics - interest congruence, interest differentiation, and general interest level (elevation) - with several indicators of career preparedness (i.e., career planning, occupational self-efficacy beliefs, career decidedness, and career engagement) among a sample of 239 university students. Controlling for sociodemographic variables, multiple regression analyses revealed that differentiation is positively associated with career decidedness and career engagement and elevation is positively related to occupational self-efficacy beliefs and career engagement. The third paper investigates how protean career orientation (PCO) is related to vocational identity clarity and occupational self-efficacy. Study 1 reports a 1-year, three-wave cross-lagged study among 563 university students and established that PCO preceded changes in identity and self-efficacy - but not the other way around. Based on a 6-month longitudinal study of 202 employees, Study 2 shows that identity clarity and self-efficacy mediated the effects of PCO on career satisfaction and proactive career behaviors. PCO only possessed incremental predictive validity regarding proactive career behaviors. However, specific direct or mediated effects of PCO on job satisfaction could not be confirmed. The fourth paper explores the relationships between narcissism and two indicators of career success (i.e., salary and career satisfaction) among a group of young professionals (N = 314). A model proposing that the effect of narcissism on career success is mediated by increased occupational self-efficacy beliefs and career engagement was assessed. While correlations between narcissism and the two indicators of career success were minimal, the results show a significant indirect effect on salary via occupational self-efficacy and indirect effects on career satisfaction via self-efficacy and career engagement. Overall, the different studies corroborate the crucial role of career preparation for a successful start into working life. In sum, this dissertation contributes to literature on vocational psychology by providing novel insights in terms of facilitators and outcomes of career preparation among university students and graduates. Theoretical and practical implications are discussed, and promising directions for future research are identified.
Expatriate success divided into two criteria, expatriate adjustment and expatriate job performance, is analyzed in relation to extraversion and its facets. Measurements of the Big Five and scales of adjustment as well as job performance were used by interviewing a sample of 80 German, Austrian and Swiss expatriates working in Costa Rica. The overall extraversion trait, gregariousness, assertiveness, and activity show meaningful effects on expatriate job performance. By analyzing expatriate adjustment and its relationship with extraversion and corresponding facets moderate effects were found between activity and interaction adjustment. Positive emotions with interaction adjustment as well as positive emotions with general adjustment show the largest effects. Furthermore, small effects were found for activity and warmth in respect to expatriate adjustment. Finally, suggestions for further research concerning extraversion in expatriate management are given.
This dissertation analyses external appointees and successions on boards and consists of three papers which are all empirical in nature. It provides insights into the present literature from a meta-perspective, enlarges the understanding of external successions to German executive bank boards and extends the rare number of studies on the internal supervisory bodies of bank institutions. The first paper highlights the existing literature: conducting a literature search process, the paper aggregates 102 empirical results from 28 journal articles and working papers published between 1990 and 2017. The meta-analysis focuses on how researchers address the build-in issue that outsiders are not randomly assigned to firms. The results reveal that the relationship of outside successions and performance varies significantly with the methodological characteristics of the original studies. The following two papers concentrate on successions in banking institutions. More specifically, the second study examines the appointments of executive directors external to the bank and the consequences of that appointment on bank performance. The study addresses in particular alternative explanations, i.e. outside selection and/or joint endogeneity, while examining external executive appointments and their consequences on bank performance. The second empirical paper lend significant support to the view that some outsiders are better predisposed to helping the bank turn around poor performance and that the selected proxies of managerial ability, which are based on the historical return on assets and risk-return efficiency measured at outsiders' former banks, are able to identify such good outsiders. Finally, the third paper considers the link between the executive and the supervisory board. The study points to the conclusion that newly appointed executives to the supervisory board differ from their non-appointed counterparts with a particular set of experiences. The study provides evidence for the view that the pre-appointment financial situation, measured by several proxies of bank risk and performance, has significant influence on the decision to appoint such an experienced member to the supervisory board. This dissertation is framed by an introduction and concluding chapter where the author reflects on the research questions of her empirical studies, summarizes the results and identifies some possibilities for future research.
This paper presents the first empirical test with German establishment level data of a hypothesis derived by Helpman, Melitz and Yeaple in a model that explains the decision of heterogeneous firms to serve foreign markets either trough exports or foreign direct investment: only the more productive firms choose to serve the foreign markets, and the most productive among this group will further choose to serve these markets via foreign direct investments. Using a non-parametric test for first order stochastic dominance it is shown that, in line with this hypothesis, the productivity distribution of foreign direct investors dominates that of exporters, which in turn dominates that of national market suppliers.
While the role of exports in promoting growth in general, and productivity in particular, has been investigated empirically using aggregate data for countries and industries for a long time, only recently have comprehensive longitudinal data at the firm level been used to look at the extent and causes of productivity differentials between exporters and their counterparts which sell on the domestic market only. This papers surveys the empirical strategies applied, and the results produced, in 45 microeconometric studies with data from 33 countries that were published between 1995 and 2004. Details aside, exporters are found to be more productive than non-exporters, and the more productive firms self-select into export markets, while exporting does not necessarily improve productivity.
Using unique recently released nationally representative high-quality longitudinal data at the plant level, this paper presents the first comprehensive evidence on the relationship between exports and productivity for Germany, a leading actor on the world market for manufactured goods. It applies and extends the now standard approach from the international literature to document that the positive productivity differential of exporters compared to non-exporters is statistically significant, and substantial, even when observed firm characteristics and unobserved firm specific effects are controlled for. For West German plants (but not for East German plants) some empirical evidence for self-selection of more productive firms into export markets is found. There is no evidence for the hypothesis that plants which start to export perform better in the three years after the start than their counterparts which do not start to sell their products on the world market. Results for West Germany support the hypothesis that the productivity differential between exporters and nonexporters is at least in part the result of a market driven selection process in which those export starters that have low productivity at starting time fail as a successful exporter in the years after the start, and only those that were more productive at starting time continue to export.
Abstract: A recent survey of 54 micro-econometric studies reveals that exporting firms are more productive than non-exporters. On the other hand, previous empirical studies show that exporting does not necessarily improve productivity. One possible reason for this result is that most previous studies are restricted to analysing the relationship between a firm’s export status and the growth of its labour productivity, using the firms’ export status as a binary treatment variable and comparing the performance of exporting and non-exporting firms. In this paper, we apply the newly developed generalised propensity score (GPS) methodology that allows for continuous treatment, that is, different levels of the firms’ export activities. Using the GPS method and a large panel data set for German manufacturing firms, we estimate the relationship between a firm’s export-sales ratio and its labour productivity growth rate. We find that there is a causal effect of firms’ export activities on labour productivity growth. However, exporting improves labour productivity growth only within a sub-interval of the range of firms’ export-sales ratios.
We use comparable micro level panel data for 14 countries and a set of identically specified empirical models to investigate the relationship between exports and productivity. Our overall results are in line with the big picture that is by now familiar from the literature: Exporters are more productive than non-exporters when observed and unobserved heterogeneity are controlled for, and these exporter productivity premia tend to increase with the share of exports in total sales; there is strong evidence in favour of self-selection of more productive firms into export markets, but nearly no evidence in favour of the learning-by-exporting hypothesis. We document that the exporter premia differ considerably across countries in identically specified empirical models. In a meta-analysis of our results we find that countries that are more open and have more effective government report higher productivity premia. However, the level of development per se does not appear to be an explanation for the observed cross-country differences.
The majority of empirical studies that centre on exporter performance and the determinants of export performance have focused mainly on the manufacturing sector, largely because there are very few datasets that facilitate a detailed investigation into the service sector. In 2008, however, the German Federal Statistical Office and the statistical offices of the Federal States released the German business services statistics panel (this dataset is described in more details in Chapter 2). Thus, for the first time, appropriate panel analyses of the export behaviour of German business services firms became possible. This thesis uses this panel dataset and contributes to the literature on the microeconometrics of international trade by providing evidence concerning the German business services sector. Overall, the results noted for exporter performance in the German business services sector correspond with those from the manufacturing sector. Chapter 3 shows that, similar to the manufacturing sector, exporting German business services firms are more productive and clearly larger (in terms of turnover and number of employed persons) than non-exporters, even when it is controlled for size and industry. Further, business services enterprises that export pay higher average wages (even when controlling for size and industry). When controlling for unobserved, time-invariant characteristics, the significant differences between exporters and non-exporters relative to productivity or average wages disappear, while significant export premia associated with the size variables continue to exist, but on a much smaller scale. Concerning the hypothesis that better performing enterprises self-select into export markets, the results indicate that in the business services sector as in the manufacturing sector, enterprises that begin to export are larger than non-exporters, even two years before they commence exporting operations. Regarding productivity (in terms of turnover per employed person) and average wages, the results were statistically significant only for business services enterprises in Germany’s western region. Aside from these similarities with the manufacturing sector, Chapter 4 presents evidence which suggests that, contrary to firms in the manufacturing industries, German business services firms do not benefit from exporting in terms of higher rates of profit. Chapter 4 documents a negative profitability differential of services exporters compared to non-exporters, and finds that export-starters in the business services sector are less profitable than non-exporters, even two years before they begin to export. Further, the estimated dose-response function, which is used to investigate the causal impact of exports on profits, shows an s-shaped relationship between profitability and firms’ export-sales ratio. Enterprises with a very small share of exports in total sales have a lower rate of profit than non-exporting firms. Then, with an increase in export intensity, the rate of profit increases as well. However, even at the maximum, the average profitability of the exporters is not, or is only slightly, higher than the average rate of profit of the non-exporting firms. Chapter 5 investigates the question which factors determine the export performance of German business services firms by estimating a model of the firms’ export intensity decision. Overall, the results support most of the explanations of export behaviour found in the literature for both service firms and manufacturing firms, such as the positive effects of size, human capital, and productivity. Yet when controlling for unobserved heterogeneity, the picture changes; notably, in the model with fixed effects, the significance of productivity and human capital disappears. This indicates that these variables are not positively related to the export performance per se, but are related instead to unobserved time-constant characteristics. Size still has a significant positive effect on exporting when controlling for unobserved effects. Finally, Chapter 6 considers the impact of the 2004 EU enlargement on service enterprises close to Germany’s eastern border by using regression-adjusted difference-in-differences estimators. The results suggest a small negative impact associated with the EU enlargement on export intensity and the turnover of large enterprises with an annual turnover of €250,000 or more, and no effect on the share of exporters and the turnover profitability of these enterprises. For small enterprises close to Germany’s eastern border, an increase in turnover and a decrease in profitability relative to other small enterprises are noted.
This paper contributes to the flourishing literature on exports and productivity by using a unique newly available panel of exporting establishments from the manufacturing sector of Germany from 1995 to 2004 to test three hypotheses derived from a theoretical model by Hopenhayn (Econometrica 1992): (H1) Firms that stop exporting in year t were in t-1 less productive than firms that continue to export in t. (H2) Firms that start to export in year t are less productive than firms that export both in year t-1 and in year t. (H3) Firms from a cohort of export starters that still export in the last year of the panel were more productive in the start year than firms from the same cohort that stopped to export in between. While results for West Germany support all three hypotheses, this is only the case for (H1) and (H2) in East Germany.
Destination websites, which are maintained by destination marketing/management organisations (DMOs), are a key source of information for tourists in the pre-trip phase. DMOs are increasingly applying experiential marketing on their websites to support positive pre-travel online destination experiences (ODEs) and make the vision of the holiday as vivid as possible. However, research into technology-driven travel experiences is still in its infancy. In particular, a theoretical understanding of the nature of ODEs arising from destination websites is still lacking. Therefore, this dissertation is dedicated to an extensive investigation of ODEs on destination websites in the pre-travel phase. The aims were to analyse the influences of experiential design on ODEs, explore the ODE dimensions, and develop and validate a measurement tool for assessing the ODE values of destination websites. In the first qualitative multi-method study (eye-tracking, retrospective think-aloud protocols, semi-structured interviews, and video observations), the objective was to gain an in-depth understanding of the ODE facets in the travel inspiration phase. It was found that the experience dimensions adopted in previous research regarding the product-brand context (sensory, affective, intellectual, social, and behavioural dimensions) also occurred in the ODE context but exhibited some particularities, such as a future-oriented affective component (affective forecasting). Moreover, a supplementary spatio-temporal experience dimension was identified. An online field experiment was subsequently conducted and aimed at assessing the effects of applying experiential marketing on destination websites on ODEs in the travel inspiration phase. Based on the findings of Study 1, an initial attempt at developing an ODE measurement instrument was made and the ODE dimensionality tested. The results showed the theoretically relevant experience dimensions to be less differentiated compared to the product-brand context; instead, they merged into a holistic ODE encompassing several experience facets. Furthermore, it was shown that the application of experiential design enhanced ODEs; however, considering the subjectivity of experiences, the effect was rather small. Accordingly, complex multi-media elements do not automatically increase the experiential effect. In the third study, a quasi-online field experiment was conducted, simulating the travel information phase (higher involvement than Study 2) to re-assess the ODE dimensions and develop and validate a measurement instrument. The results showed the overall ODE to be reflected by two interrelated dimensions that aligned with the dual process theory: hedonic and utilitarian experiences. The facets identified in the first study were largely reflected in these two overarching components. Moreover, a reliable, valid, and parsimonious second-order measure for assessing ODEs was proposed. Overall, the results yielded by this dissertation enhance the scientific understanding of the technology-empowered tourist experience in the currently under-researched pre-travel experience phase. In addition, by proposing a new scale for the measurement of ODEs, this dissertation provides useful methodological advancements that can pave the way for further research in this field.
Exploring artful possibilities: a transdisciplinary research on culture, arts and sustainability
(2021)
The texts gathered in this manuscript offer a largely congruent set of insights on the cultural dimension of sustainability and on the important functions of the arts in relation to the cultural dimension of sustainability, not only in society – more particularly in cities – but also more self- reflexively in transdisciplinary sustainability research itself. The introduction paper (original text for the Cumulative Habilitation) presents all the published texts included in the cumulative habilitation manuscript, and discusses the challenges of transdisciplinary research, differentiating two schools of transdisciplinarity (the so-called the ‘ETH’ and ‘CIRET’ approaches) to which the author’s postdoctoral research relates. The four texts in the first part (PART 1 - Culture(s) and Aesthetics of sustainability)articulate the relations between culture and sustainability. They focus on a theoretical dimension of the author’s postdoctoral research that further developed an understanding of “cultures of sustainability” and of “aesthetics of complexity” that was initiated in the author’s PhD, bringing them in a dialogue with other ongoing and emerging discourses about “cultural sustainability” and “queer ecologies”. The four texts in the second part (PART 2 - The Arts in Relation to Culture(s) and Aesthetics of Sustainability) represent the part of the author’s research that constituted a closer examination of specific artistic practices: ecological art, musical practices, and contemporary interdisciplinary arts in urban arts organizations.
The ten texts in the third part (PART 3 - Creative Sustainable Cities) share the insights gained in the parts of the author’s research work that focused on urban cultural and arts-related phenomena in their relationships to urban sustainability. Several of the texts lay out a critique of the “Creative City” and demonstrate an effort to develop an alternative understanding of the Creative City that would deserve to be also named a “Sustainable City”. Later texts share the insights from the author’s co-leading of the “Stadt als Möglichkeitsraum” (“City as Space of Possibilities”) research project (2015-2018).
The nine texts collected in the fourth part (PART 4 - Towards Artful Sustainability Research)reflect how the author’s ongoing research work included a transdisciplinary reflection and development in terms of epistemology and methodology, incorporating increasingly more elements of arts-based research and of phenomenology and integrating them with systems thinking and qualitative social-scientific research. This development brought the author to reflect further upon the imaginaries and research practices of sustainability researchers, and to advocate for an “artistic turn” in sustainability research (including the more specific field of sustainability science).
The conclusion paper (original text for the Cumulative Habilitation) summarizes the insights from all the published texts included in the cumulative habilitation manuscript, and suggests ways to address the transdisciplinary challenges presented in the introduction paper, suggesting ways to articulate the ‘ETH’ and ‘CIRET’ approaches to transdisciplinarity.
Since its establishment, the African Union (AU) has assumed an important role in matters of peace and security on the continent. This doctoral dissertation is dedicated to its conflict and crisis interventions and seeks to identify as well as subsequently explain the broader patterns that have emerged. The dissertation posits that neither the AU's regime-serving roots, which emphasize the primacy of incumbents' parochial interests, nor the AU's problem-solving commitment, which emphasizes the pursuit of its declared organizational mission, can convincingly explain these patterns on their own. Instead, we should understand the AU as being driven by two different logics of cooperation at the same time: a problem-solving and a regime-serving logic. Across its three constitutive articles, the dissertation makes empirical as well as theoretical contributions to the existing literature. Empirically, it offers a broad and systematic analysis of AU interventions over time, across different intervention types, and without bias towards high-profile cases. The novel dataset, on which the dissertation builds, constitutes the hitherto most comprehensive effort to capture the AU's responses to crises and conflicts. Theoretically, the dissertation develops a set of testable theory-driven expectations based on the notion of two different logics of cooperation. While identifiable in the literature on the AU and linking to broader existing debates on international cooperation, the dissertation breaks ground by clearly outlining the implications of each logic and bringing them together under a single theoretical framework. Jointly, the articles provided strong evidence that the AU is indeed driven by both a problem-solving and a regime-serving logic of cooperation, and that this serves as the foundation for explaining the AU's broader intervention patterns. This contributes not only to a better understanding of AU interventions but also has a chance to enrich other important debates, including the debates on African regionalism, comparative regionalism, and multilateral interventions.
Expatriate success
(2006)
Many public goods are characterized by rivalry and/or excludability. This paper introduces both non-excludable and excludable public inputs into a simple endogenous growth model. We derive the equilibrium growth rate and design the optimal tax and user-cost structure. Our results emphasize the role of congestion in determining this optimal financing structure and the consequences this has in turn for the government’s budget. The latter consists of fee and tax revenues that are used to finance the entire public production input and that may or may not suffice to finance the entire public input, depending upon the degree of congestion. We extend the model to allow for monopoly pricing of the user fee by the government. Most of the analysis is conducted for general production functions consistent with endogenous growth, although the case of CES technology is also considered.
The doctoral dissertation deals with the problems of the diagnosis of rolling bearings using recurrence analysis. The main topic is the influence of radial internal clearance on the change of dynamics in a self-aligning double-row ball bearing with a tapered bore, in which the axial preload can control this parameter in a wide range. The dissertation began with an analysis of the state of knowledge. In the next part of the dissertation, the thesis was formulated and activities related to its proving were defined. The theoretical part was supplemented with the basics related to vibroacoustic diagnostics of rolling bearings and presented methods that can be used for their diagnostics. The research on proving the thesis was started with the preparation of a mathematical model in which a change in the damping coefficient in the field of radial clearance was adopted, a difference in the clearance value for a given row of balls was proposed, and the influence of shape errors and radial shaft endplay on the dynamics of the tested bearing was taken into account. During the dynamics tests, the radial clearance was adopted as a bifurcation parameter, and on the basis of the bifurcation diagram, it was possible to indicate the characteristic areas of bearing operation due to the radial internal clearance. In order to verify the model, experimental tests were carried out with a series of bearings in which the radial clearance was changed in a wide range possible to be physically realized. Recurrence analysis was used for both the dynamic response obtained from model and experimental studies. Owing to the comparative analysis of the dynamic response, recurrence quantificators were selected that are most susceptible to changes in radial clearance to bearing dynamics. Moreover, as a result of the research, it was possible to select a narrow range of radial clearance, ensuring the smoothest operation of the tested bearing.
In the early 1990s the European Commission and the national governments of the EU member states initiated an extensive deregulation and liberalization process in the European railway industry. Prior to this process, the European railway industry was characterized by loosely connected national monopoly railway companies which faced severe losses of transportation market share and required increasing subsidies. Overall, this system was not what a single European market needed: an integrated transport system that provides reliable and fast cross-border transportation of goods, services, and people. The main elements of the reforms have been the separation of infrastructure management from transport operations, the implementation of interoperability among the national railway systems, the assurance of third-party access to the infrastructure, and the introduction of independent railway regulatory systems. In general, the intention of the reforms has been to enhance competition by opening the market and to improve the economic performance of the European railway industry. The objective of this thesis is to analyze the effectiveness of the European railway deregulation process in enhancing efficiency and productivity in the European railway industry. For that purpose three empirical papers are introduced that use non-parametric and parametric benchmarking methods to evaluate the impact of different production technologies and country- and firm-specific environmental and regulatory conditions on efficiency and productivity. The first paper, ‘Testing for Economies of Scope in European Railways: An Efficiency Analysis’, conducts a pan-European efficiency analysis to investigate the performance of European railways with a particular focus on economies of vertical integration. We test the hypothesis that integrated railways realize economies of scope and, thus, produce railway services with a higher level of efficiency. To determine whether joint or separate production is more efficient, we apply an innovative two-stage data envelopment analysis super-efficiency model which relates the efficiency for integrated production to a reference set consisting of separated firms which use a different production technology. We find that for a majority of European railways economies of scope exist. The second paper, ‘Productivity Growth in European Railways: Technological Progress, Efficiency Change and Scale Effects’, analyzes the efficiency and productivity of the European railway sector in the period of deregulation (1990-2005). Using a stochastic frontier panel data model that controls for unobserved heterogeneity a distance function model is estimated in order to evaluate the sources of productivity growth: technological progress, technical efficiency change and scale effects. The results indicate that technology improvements were by far the most important driver of productivity growth, followed by gains in technical efficiency, and to a lesser extent by exploitation of scale economies. Overall, we find an average productivity growth of 39 percent within the sample period. The third paper, ‘European Railway Deregulation: The Influence of Regulatory and Environmental Conditions on Efficiency’, investigates the impact of regulatory and environmental conditions on technical efficiency of European railways. Using a panel data set of 31 railway firms from 22 European countries from 1994 to 2005, a distance function model, including regulatory and environmental factors, is estimated using stochastic frontier analysis. The results obtained indicate positive and negative efficiency effects of different regulatory reforms. Furthermore, estimating models with and without regulatory and environmental factors indicates that the omission of environmental factors, such as network density, substantially changes parameter estimates and, hence, leads to biased estimation results. The last chapter of the thesis summarizes the results of the three empirical analyses. It contains overall conclusions, highlights implications for economic policy, and provides directions for further research.
On 25 October 2016, the European Commission presented a proposal for a directive on a Common Corporate Tax Base (CCTB Proposal), which contains a comprehensive concept for the harmonisation of profit calculation regulations within the EU. Against this current background, the objective of the present work is to contribute to the implementation of the CCTB by identifying ambiguities and conceptual weaknesses in the design of the profit determination system of the CCTB Proposal and developing concrete recommendations for action for adjustments in the course of the further legislative procedure. In the first article, selected profit calculation rules of the CCTB Proposal will be analysed in detail and compared with the provisions on profit calculation under German commercial and tax law and the International Financial Reporting Standards (IFRS) recognised across member states. Based on the legal comparison, questions of interpretation and inadequacies of the profit calculation system will be considered and proposals for adjustments to various regulatory areas will be submitted. Furthermore, in the second article, within the framework of a holistic study, expert interviews will be used as an empirical-qualitative research design to generate reliable assessments on the part of the various stakeholder groups affected by the implementation of the future directive or involved in its elaboration. The results show the extent to which the profit determination rules of the CCTB Proposal in their current form are suitable for national and EU-wide implementation and in which areas the various expert groups still see concrete need for adaptation. Based on these expert assessments, the third article finally develops a proposal to reduce the threat of legal uncertainty in interpretation issues criticised by the experts. Based on economic maxims developed by the European Commission and existing accounting principles of the current CCTB Proposal, the EU Accounting Directive and IFRS, a system of specific European tax principles will be developed which could be implemented within the framework of the CCTB Proposal.
This research work aims to create a theoretical base for new urban planning guidelines involving a comprehensive study of housing in Damascus with emphasis on social and cultural factors. The research starts with a historical review of the Muslim City in general and distinguishes between cities that existed before Islam and then were conquered and modified by Muslims and cities established by Muslim Authority. The focus is only on the residential quarters in the city and the local market, mosque and etc (outside the old walled city of Damascus). Other Muslim city urban elements such as Grand mosque, caliph's residency, Citadel and etc. are not in the scope of this study. A brief historical review of Damascus before and during Islam and the development of residential quarters are illustrated. Later, the study analyzes the traditional residential quarter and explores the building guidelines that governed the evolution of the built form of the quarter. Then, the study explores the multi-faceted changes (economic, social and political) that the Middle Eastern region went through, in the last century, in general and the effect of those changes on the city form, case of Damascus. The effect will be traced through examining the decrees that the Authority issued in order to govern land reform and manage public and private domains. Then, the study looks at the ramifications of those decrees on the urban form of Damascus. It also investigates the decrees that were the guide for new planning and organizing developments. The study will inspect the end products of the planning and organizing process by studying several cases of building permits. Then, provides morphology of the new residential sub-quarter and its urban form. Based on lessons learned from the previous decades of housing policy, the study will recommend foundation for governmental norms to produce responsive physical and social urban forms.
In 2013, the European Commission adopted the so called "Entrepreneurship 2020 Action Plan" to ease the creation of new ventures and to support the takeover of existing firms. The goal is to create a supportive environment for entrepreneurs to thrive and grow (European Commission 2013). This shows that the European Union puts its efforts to support small firms as they are seen as means for Europe's sustainable economic growth. However, the successful processes of growth and investment are complex and depend on different determinants. The present thesis focuses on the firm level and analyzes in three independent articles: how small firms invest over time, how new ventures grow and which variables influence growth, how small firms grow after business takeover and which variables influence growth. The framework that connects these articles forms the content-related focus on the early stage of development of small firms and the methodological and analytical approaches that comply with up-to-date and adequate statistical analysis techniques. Supported by an extensive dataset, which is the foundation of all three articles, it is possible to investigate empirically different open research questions using bivariate and multivariate analysis techniques. Thus, this thesis also serves the research needs for more multivariate analyses for small firms, for which so far mainly cross-sectional studies have been conducted.
Essays on Say-on-Pay: theoretical analysis, literature review and empirical evidence from Germany
(2019)
The dissertation contains four journal articles together with a framework manuscript. The overall subject is the so-called Say-on-Pay (SOP) vote. SOP is a law that enables shareholders to vote on the appropriateness of executive compensation during the firms’ annual general meeting. The dissertation investigates SOP votes from different angles. While the framework provides a background for the relevance of the work, outlines existing research gaps, covers an in-depth discussion and concludes relevant research questions, the four articles present the essence of the dissertation. The first article is a theoretical paper on the recent advances of behavioural agency theory. It serves as a theoretical foundation for the empirical work of the dissertation. Although principal-agent theory has gained a prominent place in research, its negative image of self-serving managers is frequently criticized. Consequently, scholars advocate the utilization of positive management theories, such as stewardship theory. This paper reviews the literature of both theoretical concepts and describes how behavioural characteristics allow for a mutually beneficial symbiosis of the two theories. The second article establishes the foundation of the scholarly knowledge in the field by systematically reviewing the empirical literature. The review covers 71 empirical articles published between January 1995 and September 2017. The studies are reviewed within an empirical research framework that separates the reasons for shareholder activism and SOP voting dissent as input factor on the one hand and the consequences of shareholder pressure as output factor on the other. The implications are analysed, and new directions for further research are discussed by proposing 19 different research questions. Building on the research gaps defined in the literature review, the third article is an empirical manuscript. In this paper, a hand-selected sample of 1,676 annual general meetings with 268 management-sponsored SOP votes in 164 different companies between 2010 and 2015 in Germany is analysed. The analysis focused on the structure, rather than the level, of executive compensation by applying a sample-selection model and panel data regression. Finally, the fourth paper investigates the rare setting of voluntary SOP votes. Using 1,841 annual general meetings of listed firms in Germany between 2010 and 2016, the effects of financial and non-financial (sustainable) performance on SOP voting likelihood and voting results are tested.
In this dissertation, the author focuses on the link between (internal) corporate governance structures and processes and firms financial reporting quality. Specifically, the dissertation aims to provide insights into the following general research question: What is the effect of different corporate governance stakeholders on the financial reporting quality of a firm? The author provides insights into this question through three different articles. Paper #1 explores the relationship between family firm status and earnings management and synthesizes and explains previous research findings with the help of meta-analytic methods that are still uncommon in financial accounting research. The authors find a negative relationship between family firms and earnings management on average across 37 primary studies (and 305 effect sizes in total). Furthermore, they show that the considerable variation in size and direction of primary effect sizes can be explained by researchers choice of study design, earnings management proxy and different institutional settings. The second paper explores institutional owners as a different set of shareholders and their impact on financial reporting quality. The study enables the authors to compare the results against the backdrop of the previous chapter and to see different rationales that managers in institutionally-owned companies might have to engage in earnings management. Here, the authors study 511 effect sizes from a total of 87 primary studies and find that the average effect is slightly negative, meaning institutional owners on average can get more transparent earnings figures from the companies they invest in. Similar to the work they did on family firms, they find considerable heterogeneity between results from primary studies. Specifically, their multivariate meta-regression models can explain 26% of the variability in effect sizes, mainly attributable to study design choices. The third paper is concerned with managers and how managerial personality drives the propensity to engage in fraudulent accounting activities. The author uses a primary sample of 956 professionals, who work in accounting and finance departments, and ask them to rate their immediate superior on dark triad personality traits, as well as common actions taken by management to obscure and manipulate earnings figures. He finds that managers with high ratings for dark triad personality traits engage to a greater extent in fraudulent accounting practices, than managers scoring low on the dark triad scale. Moreover, the author can show that traditional risk management mechanisms, like internal audit departments, are only partially effective. Specifically, he finds that only internal audit departments that are fully staffed by external personnel can curb the adverse effect of dark triad managers on financial reporting quality. This suggests that managers with dark personalities can take advantage of mixed or entirely in-house internal audit departments. Overall, this dissertation contributes significantly to both literature streams of corporate governance and financial reporting quality. This work can explain a significant degree of heterogeneity in previous findings on the link between different kinds of ownership and earnings management. Further, it stresses that the considerable variation in current findings is not mainly attributable to cross-country differences, as previously suggested, but in no small part attributable to study design features. Finally, the author can provide additional evidence on current research linking executive personality traits and financial reporting practices.
This dissertation is based on three empirical studies on the thematic complex of the comparative advantages of self-employment and business start-ups out of unemployment. The first study examines the characteristics of persons who present a broad range of experience in terms of professional competencies. The extent to which self-reported entrepreneurial competence and the assessment of professionally self-employed activities correlate with the number of professional competencies acquired is examined in particular. It emerged from previous studies that the tendency to establish new businesses increases with the variety of experience. More recent studies show, however, that different causes may lie behind this correlation. The results of this study show that both entrepreneurial competence and the estimation of self-employment increase with the number of professional competencies. However, the analyses would indicate that entrepreneurial competence (self-assessment) is more strongly correlated and that an actual increase in qualifications lies behind the self-assessed entrepreneurial competence. Moreover, it emerges that self-assessed entrepreneurial competence increases at decreasing marginal rates with the number of professional competencies. The second study examines the extent to which professional background and, in particular, the professional and employment experience of an individual influence the duration he or she remains in self-employment. This is studied on the basis of data from a survey of founders who become self-employed out of unemployment. The study is based on the idea that individual characteristics can be used productively in different forms of employment and that specific competence and comparative characteristics affect the time-dependent exit from self-employment. The results initially confirm previous findings, in particular that firm characteristics do not play a very significant role in the decision to start up a business from a position of unemployment. Broad-based qualifications plus business skills, a high level of intrinsic motivation for self-employment and exploitable professional experience display a strong positive correlation with the duration in self-employment; this would suggest corresponding comparative advantages for self-employment. However, business skills alone reduce the time-dependent probability of survival in self-employment and accelerate exits into employment. The third study analyzes features of local labor markets in terms of their influence on the duration of self-employment. The basis of the study is provided by process-produced data generated by the German Federal Employment Agency on the employment biographies of individuals who received support in establishing businesses with a view to exiting unemployment. Individual characteristics were examined in addition to regional determinants. The idea behind the study is that local labor market conditions can have different comparative effects on income possibilities in both positions of employment and self-employment. The exit from self-employment is described as a change in work activity which arises following the evaluation of different income options. The results show that local labor market conditions have a considerable influence on the duration of self-employment and that the effect of local labor market conditions is very complex. The results would prompt the expectation that a one-dimensional perspective based on the local unemployment rate does not provide an adequate measure of general economic conditions. Increasing regional unemployment reduces the duration of self-employment while increasing uncertainty on the local labor market results in its extension. Moreover, all local characteristics display reducing to reversing marginal effects. Tests of individual characteristics show that persons from small businesses, master craftsmen and foremen, and persons with high income premiums remain longer in their last employment situation than the controls. These characteristics are clearly associated with comparative advantages for self-employment. The study also corroborates the impression that people with business backgrounds quickly leave self-employment for employed positions.
All of the papers contained in this thesis address the topic of population economics, especially in relation to labor markets. The first chapter, Introduction, gives an overview of the papers discussed in this thesis. In the second chapter, Age and Gender Differences in Job Opportunities, job opportunities for older workers are analyzed. Newly-employed women and men who are older than the age of 55 are more limited in their occupational choices than younger women and men. Different measures of segregation such as the Duncan Index and Hutchens Index show unequal distribution of jobs over age. Older women in particular face the highest segregation. Several years of the IAB Employment Sample are used in the analysis. In the third chapter, Explaining Age and Gender Differences in Employment Rates: A Labor Supply Side Perspective, the labor supply of older individuals is analyzed. The comparison of reservation wages and entry wages shows age- and gender-specific differences. Nonemployed individuals at the age of 55 and older have the highest reservation wages. Reservation wages for females are always higher than those for males. Entry wages increase with age for males, but not for females. Furthermore, the job satisfaction of women decreases with age while satisfaction with leisure tends to increase. This may explain why employment rates for females are lower than for males. The German Socio-Economic Panel (GSOEP) data is used in the paper. In the forth chapter, Somewhere over the Rainbow: Sexual Orientation Discrimination in Germany, sexual orientation-based differences in income are analyzed. Although Germany has an anti-discrimination law that has explicitly prohibited discrimination on the basis of sexual orientation since 2006, there are significant income differences for gay men and lesbian women. While gay men have an income discount of 5 to 6 percent relative to married heterosexual men, lesbian women have an income premium of 9 to 10 percent relative to heterosexual married women. These differences within the gender types can be explained partially by selection into specific occupations and sectors. One wave of the German Mikrozensus data is used in the analysis. The fifth chapter, A Note on Happiness in Eastern Europe, is no more related to Germany, but takes an international position. Estimations on life satisfaction show typical results, such as a u-shaped effect in relation to age. Marriage and a good state of health have positive effects on life satisfaction or utility, while individual unemployment has a negative effect. Several years of the European Values Study (EVS) and the World Value Survey (WSV) are used in the paper. The thesis is finished by a final chapter, Conclusion
This cumulative dissertation embraces four empirical papers addressing socio-economic issues relevant to policy-makers and society as a whole. These papers cover important aspects of human life including health at birth, life satisfaction, unemployment periods and retirement decisions. The analyses are carried out applying advanced econometric methods and are based on data sets consisting of survey data as well as administrative records. The first joint paper investigates the causal impact of prenatal exposure to air pollution on neonatal health in Italy in the 2000s combining detailed information on mother's residential location from birth certificates with PM10 concentrations from air pollution monitors. Variation in local weekly rainfall is exploited as an instrumental variable for non-random air pollution exposure. Using quasi-experimental variation in rainfall shocks allows to identify the effect of PM10, ruling out potential bias due to confounder pollutants. The paper estimates the effect of exposure for both the entire pregnancy period and separately for each trimester to test whether the neonatal health effects are driven by pollution exposure during a particular gestation period. This information enhances our understanding of the mechanisms at work and help prevent pregnant mothers from most dangerous exposure periods. Additionally, the effects of prenatal exposure to PM10 are estimated by maternal labor market status and maternal education level to understand how the pollution burden is shared across different population groups. This decomposition allows to identify possible mechanisms through which environmental inequality reinforces the negative impact of early-life exposure to air pollution. This study finds that average PM10 and days with PM10 level above the hazard limit reduce birth weight, gestational age, and measures of overall newborn health. Effects are largest for third trimester exposure and for low-income and less educated mothers. The second joint paper updates previous findings on the total East-West gap in overall life satisfaction and its trend by using data from the German Socio-Economic Panel for the years 1992 to 2013. Additionally, the effects are separately analyzed for men and women as well as for four birth cohorts. The results indicate that reported life satisfaction is, on average, significantly lower in East than in West German federal states and that part of the raw East-West gap is due to differences in household income and unemployment status. The conditional East-West gap decreased in the first years after the German reunification and remained quite stable and sizable since the mid-nineties. The results further indicate that gender differences are small. Finally, the East-West gap is significantly smaller and shows a trend towards convergence for younger birth cohorts. The third joint paper explores the effects of a major reform of unemployment benefits in Germany on the labor market outcomes of individuals with some health impairment. The reform induced a substantial reduction in the potential duration of regular unemployment benefits for older workers. This work analyzes the reform in a wider framework of institutional interactions, which allows to distinguish between its intended and unintended effects. The results based on routine data collected by the German Statutory Pension Insurance and a Difference-in-Differences design provide causal evidence for a significant decrease in the number of days in unemployment benefits and increase in the number of days in employment. However, they also suggest a significant increase in the number of days in unemployment assistance, granted upon exhaustion of unemployment benefits. Transitions to unemployment assistance represent an unintended effect, limiting the success of a policy change that aims to increase labor supply via reductions in the generosity of the unemployment insurance system. The fourth, single-authored paper explores how an increase in the early retirement age affects labor force participation of older workers. The analysis is based on a social security reform in Germany, which raised the early retirement age over several birth cohorts to boost employment of older people and ultimately alleviate the burden on the public pension system. Detailed administrative data from the Federal Employment Agency allow to distinguish between employment and unemployment as well as disability pensions and retirement benefits claims. Using a Regression Kink design in a quasi-experimental framework, the author shows that the raised early retirement age had positive employment effects and negative effects on retirement benefits claims. The results also show that some population groups are more sensitive to a reduction in retirement options and more likely to seek benefits from other government programs. In this respect, the author finds that workers in manufacturing sector respond to the raised early retirement age by claiming benefits from the disability insurance program designed to compensate for reduced earnings capacity due to severe health problems. The treatment heterogeneity analysis further suggests that high-wage workers are more likely to delay exits from employment, which is in line with incentives but might also indicate an increased inequality within the affected birth cohorts induced by the reform. Finally, women seem to rely on alternative sources of income such as retirement benefits for women, or spouse's or partner's income not observed in the data. All things considered, workers did not adjust to the increased early retirement age by substituting early retirement with other government programs but rather responded to the reform in line with the policy intent. At the same time, the findings point to heterogeneous behavioral responses across different population groups. This implies that raising the early retirement age is an effective policy tool to increase employment only among older people who have the real choice to delay employment exits. Therefore, reforms that raise statutory ages should ensure social support for workers only marginally attached to the labor market or not able to work longer due to potential health problems or other circumstances.
Many dynamics are reshaping the global macroeconomics and finance. This cumulative dissertation empirically examines the impacts of two major global dynamics, the disaster risks and the China's rise, on the global economy. Chapter 1 introduces the motivation and summarizes the dissertation. Chapter 2 investigates how geopolitical risks affect financial stress in the whole financial system and its sub-sectors (banking, stock, foreign exchange, bond) of major emerging economies. Chapter 3 shows how different disaster risks (financial, geopolitical, natural-technological) can explain the returns and risk premiums of stock and housing in advanced economies between 1870 and 2015. Chapter 4 examines how the rise of China is contributing to higher economic growth in emerging economies, especially after the Global financial crisis of 2007-2008. Chapter 5 illustrates how a close trade and investment relation with China has helped African countries to reduce poverty and to improve their income distribution.
This dissertation comprises three stand-alone research papers dealing with different aspects of labor market characteristics: bonus payments and the gender pay gap; second job holding; and workers un-covered by collective bargaining. The first paper investigates whether and how non-base compensation in the form of bonus payments, overtime pay, and shift premia contributes to the gender pay gap. Unionization along with collective bargaining coverage has been on the decline on recent decades. Using German administrative data, the second paper examines which workers in firms covered by col-lective bargaining agreements still individually benefit from these union agreements, which workers are not covered anymore and what this means for their wages. The third paper studies the development and persistence of second job holding in Germany after a legislative change in the year 2003 allowed the extensive dispensation of marginal second jobs from taxes and social security contributions. Using data from the German Socio-Economic Panel, the author documents a substantial increase in second job holding in Germany since 2003 and finds in a dynamic panel model setting that there is true state dependence in second job holding.
All of the papers contained in this thesis deal with some aspect of labor market inequality. The impact of September 11th, 2001 on the employment prospects of Arabs and Muslims in the German labor market (chapter 2) examines whether the attacks on the World Trade Center and the Pentagon on September 11th, 2001 have influenced the job prospects of persons from predominantly Muslim countries in the German labor market. Using a large, representative database of the German working population, evidence from regression-adjusted difference-in-differences-estimates indicates that 9/11 did not cause a severe decline in job prospects. This result, which is in line with prior evidence from Sweden and England, is robust over a wide range of control groups. Islamistic terror and the job prospects of Arab men in Britain: Does a country's direct involvement matter? (chapter 3) examines whether the labor market prospects of Arab men in England are influenced by recent Islamistic terrorist attacks. We use data from the British Labour Force Survey from Spring 1999 to Winter 2006 and treat the terrorist attacks on the USA on September 11th, 2001, the Madrid train bombings on March 11th, 2004 and the London bombings on July 7th, 2005 as quasi-experimental events that may have changed the attitudes towards Arab or Muslim men. Using treatment group definitions based on ethnicity, country of birth and religion, evidence from difference-in-differences-estimators combined with matching indicates that the real wages, hours worked and employment probabilities of Arab men were unchanged by the attacks. This finding is in line with prior evidence from Europe. Effects of the obligation to employ severely disabled workers - findings from the introduction of the Law to Combat Unemployment among Severely Disabled People'' (chapter 4) uses new administrative data from the German Federal Employment Agency -- the Integrated Employment Biographies Sample IEBS -- to assess the impact of a mandatory employment quota for disabled workers in Germany. We use an exogenous change, introduced through the Law to Combat Unemployment among Severely Disabled People'' (Gesetz zur Bekämpfung der Arbeitslosigkeit Schwerbehinderter''), as a natural experiment and measure the change in the reemployment probability of the unemployed disabled by means of regression-adjusted difference-in-differences estimators. Our results indicate that the change in the employment quota neither enhanced nor worsened the employment prospects of the disabled. Finally, Intra-firm wage inequality and firm performance -- First evidence from German linked employer-employee-data (chapter 6) deals with the impact of wage inequality on firm performance. Economic theory suggests both positive and negative relationships between intra-firm wage inequality and productivity. This paper contributes to the growing empirical literature on this subject. We combine German employer-employee-data for the years 1995-2005 with inequality measures using the whole wage distribution of a firm and rely on panel-instrumental variable estimators to control for unobserved heterogeneity and simultaneity problems. Our results indicate a relatively small impact of wage inequality on firm performance in West Germany, while there seems to be a relationship for some inequality measures in East Germany. Further analysis shows that the relationship varies strongly with industrial relations in East Germany.
Against the background of recent economic attempts to explain individual economic decisions by structural and institutional factors, this thesis examined to what extent cultural norms exhibit quantitatively important explanatory power for individual economic outcomes, namely individual’s savings and working choices. While an extensive literature deals with the relation between culture and aggregate economic outcomes, those results obtained may reveal distorted cultural effects due to unobserved omitted variables at the country level. Thus, for the purpose of this thesis, four empirical studies were conducted based on individual and household level data for the USA and Germany, respectively. Due to difficulties in defining a coherent concept of culture, Chapters 2 to 4 use individual religiosity, as measured by one’s religious affiliation and religious involvement, as a proxy for culture. Using individual survey data for the USA, namely the PSID, for the years 2003 to 2009, the aim of Chapter 2 was, firstly, to analyze the extent to which religious beliefs and religious commitment are associated with distinct individual savings behavior as a basis for culture-induced heterogeneity in aggregate economic outcomes. One’s religiosity was found in the cross-sectional analysis to be a robust determinant of individual savings choices, even once I control for differences in individual characteristics. To identify the causal effect of religion on individual savings choices, secondly, the results from the multivariate analysis were verified by using the longitudinal structure of the PSID and by an instrumental variable approach, where own individual religious belief were instrumented with the share of one’s religious tradition in the region of ancestry. Neither of these approaches was able to replicate the positive relation between religious affiliation and savings behavior found in the cross-sectional analysis Although the estimates are subject to inefficiencies due to data limitations, this paper mainly sheds light on the endogeneity bias inherent in the relation between cultural factors and economic outcomes. However, taking actively part in religious activities was found to affect the amount saved positively. Thus, one may argue that religious traditions impose religious rules and establish social networks that enhance an individual’s ability and willingness to save money. As opposed to the vital religious market in the USA, Chapters 3 and 4 analyzed the relationship between individual religiosity and risk-taking preferences as well as individual financial behavior within Germany. Using German micro-data, namely the GSOEP, for the years 2003 and 2004, while controlling for the overall level of general risk assessment, evidence is provided that different religious affiliations are associated with distinct financial risk taking attitudes as well as with distinct individual propensities to trust strangers, another central determinant of a household’s financial choices. Further, the extent to which religion-induced heterogeneity in risk-taking preferences actually influences investment and trusting decisions of households in Germany was examined. As compared to the results obtained for the relation between religiosity and savings behavior in the USA, the main differences in economic attitudes and behavior in Germany occur between Christian and Non-Christian religions. However, religious networks were found in both countries to be more important for economic outcomes than religious belief. Chapter 5 purposed to replicate epidemiological studies conducted for North America (Fernández, 2007; Fernández and Fogli, 2009; Gevrek et al., 2011) in Germany using a quite smaller sample which were drawn from data provided by the GSOEP for the years 2001 to 2011. Applying probit and Tobit estimation techniques the results contradict the findings obtained by these previous contributions. While cultural norms towards labor market behavior of women, as measured by past female LFP rates in the country of own or parental origin, were found to be negatively associated with labor market outcomes for first-generation immigrant women in Germany, no statistically significant relation was revealed for the second generation. However, in accordance with the findings from Chapters 2 to 4, religiosity, and especially the Islamic belief, was showed to be negatively related to labor market outcomes of both generations.
This paper-based dissertation deals with the concepts of economic heterogeneity and environmental uncertainty from different perspectives, and at multiple levels of abstraction. At its core sits the observation that heterogeneity and uncertainty are deeply entangled, for there would be no uncertainty without heterogeneity of options to act regarding multiple future states of the world. At the same time, heterogeneity - in the form of diversification - has been suggested as a way to reduce uncertainty in portfolio theory (Markowitz 1952). The dissertation evolves around two research foci: (1) methodological implications of heterogeneity of scientific theories in the face of empirical data (Paper 1), and (2) two different forms of uncertainty are considered, environmental risk (Paper 2) and Knightian uncertainty (Paper 3). Paper 1 develops a new framework for model selection for the special case of fitting size distribution models to empirical data. It combines Bayesian and frequentist statistical approaches with the criterion of model microfoundation, which is to select, all other things considered being equal, the model that comes with a suitable micromodel, that explains, from the perspective of the individual constituent, the genesis of the overall size distribution. The approach is subsequently illustrated with size distribution data on commercial cattle farms in Namibia. We find that the double-Pareto lognormal distribution fits the data best. Our approach might have the potential to reconcile one of the oldest debates in current economics, i.e. the one about the best model to describe and explain the distribution of economic key variables such as income, wealth and city sizes in a country. The second paper revisits the Namibian commercial cattle farm data and uses it to put some theories from the agricultural economics literature regarding farm management under environmental risk to an empirical test. We focus on the relations between inter-annual variability in rainfall (environmental risk), risk preferences, farm size and stocking rate. We demonstrate that the Pareto distribution - which separates the distribution into two parts - is a statistically plausible description of the empirical farm size distribution when ´farm size´ is operationalized by herd size, but not by rangeland area. A statistical group comparison based on the two parts of the Pareto distribution shows that large farms are on average exposed to significantly lower environmental risk. Regarding risk preferences, we do not find any significant differences in mean risk attitude between the two branches. Our analysis confirms the central role of the stocking rate as farm management parameter, and shows that environmental risk and the farmer´s gender are key variables in explaining stocking rates in our data. Paper 3 develops a non-expected-utility approach to decision making under Knightian uncertainty which circumvents some of the conceptual problems of existing approaches. We understand Knightian uncertainty as income lotteries with known payoffs but unknown probabilities in each outcome. Based on seven axioms, we show that there uniquely (up to linear-affine transformations) exists an additive and extensive function from the set of Knightian lotteries to the real numbers that represents uncertainty preferences on the subset of lotteries with fixed positive sum of payoffs over all possible states of the world. We define the concept of uncertainty aversion such that it allows for interpersonal comparison of uncertainty attitudes. Furthermore, we propose Renyi´s (1961) generalized entropy as a one-parameter preference function, where the parameter measures the degree of uncertainty aversion. We illustrate it with a simple decision problem and compare it to other decision rules under uncertainty (maximin, maximax, Laplacian expected utility, minimum regret, Hurwicz).
Perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been widely used since 1950 in various consumer products as well as in industrial applications owing to their unique properties, e.g. being hydrophobic and lipophobic at the same time. Nowadays, some of these persistent and man-made PFASs can ubiquitously be found in humans, wildlife and various environmental media. One prominent representative of concern, belonging to the subgroup of perfluorocarboxylates (PFCs) and their conjugate acids (PFCAs), is perfluorooctanoat (PFO) and its conjugate acid (PFOA). Because of its adverse effects on human health and its persistency in the environment industry has started to replace PFO(A) and related long chain chemicals (with seven and more fully fluorinated carbon atoms) with so-called short chain PFASs (less than seven fully fluorinated carbon atoms), including precursors of PFC(A)s. Also these short chain PFC(A)s are persistent and can already be found in humans, ground- and drinking water and in remote regions. However, knowledge gaps exist in understanding the partitioning and the resulting mobility of short chain PFC(A)s in the environment. This is due to the fact that partitioning data of PFC(A)s from standardised experiments can easily be biased by various artefacts, e.g. self-aggregation of the molecules. Therefore, the objectives of this thesis are (i) to quantify the partitioning of PFC(A)s into mobile environmental media, (ii) to show how results from non-standard tests can be used to assess substance properties of concern and (iii) to conclude on whether the environmental exposure to short chain PFC(A)s is of concern from a regulatory point of view. In the first part of this thesis, the environmental mobility of short chain C4-7-PFC(A)s was investigated by quantifying their partitioning under non-standardised semi-environmental conditions into mobile environmental media, focusing on water and air, and comparing it to long chain PFC(A)s. Results are: Partitioning between water and particles in the aeration tank, primary and secondary clarifier of a wastewater treatment plant (WWTP) showed no distinct differences for short chain PFC(A)s compared to their long chain homologues (Paper 1). In a water-saturated sandy sediment column short chain PFC(A)s were not retarded, whereas long chain homologues were retarded by sorption to the sediment (Paper 2). Atmospheric particle-gas partitioning showed a lower fraction sorbed to particles for short chain PFC(A)s compared to long chain ones in samples from a WWTP (Paper 3). Air-water concentration ratios based on samples from the tanks of a WWTP were found to be higher for short chain PFC(A)s compared to long chain PFC(A)s (Paper 1). Additionally, in a newly developed experimental set-up the water to air transfer was used to derive that the pKa of C4-11-PFCAs must be <1.6 instead of up to 3.8 as reported in the literature (Paper 4). Overall, in the investigated systems short chain PFC(A)s showed a higher mobility due to a more pronounced partitioning into mobile environmental media compared to long chain PFC(A)s. In the second part of the thesis it was shown how PFO(A) - owing to its persistent, bioaccumulative and toxic (PBT-)properties – was in the context of this thesis successfully assessed as a substance of very high concern according to the criteria of the European REACH Regulation (EC No 1907/2006) by using data from non-standard tests (Paper 5). In conclusion, based on the knowledge of the high environmental mobility of short chain PFC(A)s and taking into account the argumentation of the PBT-concern of PFO(A), environmental exposure to short chain PFC(A)s is of concern and existing knowledge is already sufficient to initiate measures to prevent emissions of short chain PFC(A)s and their precursors into the environment.
The fact that digitalization comes along with a lot of negative effects onto the environment is slightly known in the case of energy consumption by hardware, especially regarding mobile devices, having a limited battery life. However, awareness of environmental issues of software, being the driver of hardware, is mainly missing, even if the research field addressing corresponding issues is growing. Thus, the doctoral thesis at hand addresses the question How to draw (a) developers and (b) usersattention to environmental issues of software? By presenting (a) a calculation method of the carbon footprint of software projects and (b) a concept for an eco-label for software products, evaluated by a user survey, the doctoral thesis provides two strategies how to draw the attention to environmental issues of software. Summarizing, this thesis can act as a basis for further research in bridging from science to society in the context of environmental issues of software. Its findings can be seen as starting points for practical implementations of methods and tools supporting a more environmentally friendly way of developing software and informing about environmental issues of software usage. In order to get the implementation of the research results of the thesis going, it highlights practical implications for diverse groups of stakeholders - researchers, certifiers, public administration and professional purchasers, and environmental associations - that have been identified as being important for the practical implementation of the presented concepts and, thus, represent the target group of the doctoral thesis.
Environmental governance beyond borders: Governing telecoupled systems towards sustainability
(2023)
This doctoral dissertation analyses the environmental governance of long-distance social-ecological interactions in telecoupled systems in two issue domains: global commodity chains and infrastructure projects as part of China’s Belt and Road Initiative (BRI). Although both domains involve different governance actors, institutions and processes, they both concern the question of how the involved actors develop governance structures and institutional responses to telecoupling. This dissertation aims to contribute to a deeper understanding of how to govern environmental problems that are associated with global flows. Since many multilateral environmental governance initiatives have not yet produced the desired solutions to global problems, particular attention is directed at unilateral state-led governance approaches. This dissertation addresses the questions of (1) how to achieve a spatial fit between the scale of telecoupled systems and the scale of governance institutions, (2) how governance actors exercise agency in governing telecoupled systems, and (3) how state actors can govern the domestic and foreign environmental effects of telecoupled flows. The results show that creating a spatial fit in the governance of global commodity flows is challenging because boundary and resolution mismatches can emerge. Boundary mismatches denote situations where social-ecological problems transcend established jurisdictional boundaries, whereas resolution mismatches refer to governance institutions that have too coarse a spatial resolution to allow them to address the specific aspects of social-ecological problems effectively. No single governance institution is likely to avoid all mismatches, which highlights the need to align multiple governance approaches to effectively govern telecoupled systems.
In the discourse on pharmaceuticals in the environment, hardly any attention has been paid to anticancer drugs. Because of their none-selective modes of action, that is, because they affect both cancerous and healthy cells, these drugs are regarded as potentially carcinogenic, genotoxic, mutagenic, and teratogenic substances. It is, however, not known how and to what extent these substances affect organisms and the environment in the long run. For this reason, this dissertation evaluated, addressing several endpoints and using organisms from different trophic levels and in silico predictions, the fate (bio- and photo degradation) and ecotoxicity of these substances. Four anticancer drugs (cyclophosphamide (CP), 5-fluorouracil (5-FU), methotrexate (MTX), and imatinib (IM) were selected. None of these anticancer compounds can be classified as ´readily biodegradable,´ a classification that indicates that biodegradation will only play a minor role in the elimination of these compounds and that they cannot be removed by the conventional processes used in sewage treatment plants and will most likely remain in the water cycle. Despite the high degrees of mineralization achieved in advanced (photo)oxidation processes, it was not possible to fully mineralize the compounds, a result that indicates that transformation products were created during these reactions. The ecotoxicity assays performed with V. fischeri indicated that 5-FU was, of all the substances tested, likely to be the most toxic (very toxic), followed by MTX (toxic) and IM (toxic/harmful), whereas CP was nontoxic. MTX presented the highest phytoxicity activity in the Lactuca sativa assay, followed by 5-FU, IM, and CP. The results of the tests performed with A. cepa showed cytotoxic (5-FU, MTX, and CP) and genotoxic effects (5-FU, CP, and IM) and mutagenic activity (5-FU, MTX, CP, and IM) of the compounds. Photo transformation products (PTPs) of CP, MTX, and 5-FU were nontoxic towards V. fischeri. However, some PTPs formed during the photodegradation of 5-FU led to positive mutagenic and genotoxic alerts in several in silico models. Not one of the compounds examined in this dissertation is likely to be fully eliminated from the water cycle by (natural) photolysis and/or advanced oxidation. Moreover, some of the treatments resulted in the formation of stable intermediates that were even less biodegradable than parent compounds. This finding shows that it is not enough to focus on primary elimination because TPs are not necessarily better biodegradable than their respective parent compounds. As indicated by the genotoxic and mutagenic positive alerts presented by different in silico models, the PTPs observed here are likely to require, despite their lower toxicity in comparison to the parent compounds, screening after treatments.
This study aims to answer four main research questions regarding the roles, strategies, barriers, and representation of the media and environmental nongovernmental organisations (ENGOs) in environmental communication in Malaysia. From a theoretical lens, this study has incorporated the essential concepts of media, ENGOs, and environmental communication from both Western and Asian, particularly Malaysian perspectives as primary points of reference. For the purpose of this study, a total of 13 interviewees from Media A and Media B and 11 interviewees from ENGO A and ENGO B were chosen for the qualitative interview while 2,050 environmental articles were collected as samples from Media A´s and Media B´s newspapers along with ENGO A´s and ENGO B´s newsletters from the period 2012 to 2014 for the quantitative content analysis. Specifically, the findings from interview confirmed that both the Malaysian media and ENGOs have shared quite similar roles in environmental communication, particularly in environmental legitimacy (creating trust, credibility, and relationships with the public), in democracy (acting as a watchdog and mobilising the public sphere), and in constructing public mind about environmental problems. Pictures undoubtedly were one of the most vital tools in social construction, especially for presenting the reality of the environmental problems to the public. This was in harmony with the results of the quantitative content analysis, where more than 60% of pictures were found on environmental articles in media newspapers and ENGOs newsletters. Malaysian media and ENGOs have shared two common strategies in environmental communication, namely campaigning and collaboration with other stakeholders, while the ENGOs have two extra strategies: advocacy and lobbying strategies. Malaysian media and ENGOs also have collaborated with each other and the level of collaboration between them was at the coordination (medium) level. Both social actors especially the media were also relied heavily on their sources for environmental articles and the result of quantitative content analysis showed that the government was the main source for media newspapers, whereas other ENGOs and laypersons were the main sources for ENGOs´ newsletters. There are also colossal barriers faced by both Malaysian media and ENGOs throughout the process of environmental communication and some of the barriers faced by both media and ENGOs include the problem with limited knowledge of the environment, while some other barriers, like media laws and ownership, were only faced by the media; other barriers such as funding problems were specifically faced by the ENGOs. In terms of representation of environmental information, the Malaysian media make more presentations on environmental problems, especially on topics like floods, wildlife and water crises in their newspapers, while ENGOs have given more attention to environmental effort topics such as conservation and sustainable living in their newsletters. Surprisingly, not only the media but also the ENGOs used the same (news) values like timeliness, proximity, and impact as criteria for the selection of environmental issues for their publications. Other factors such as the background of the organisation and the interest of journalists or editors also influence the selection of environmental issues. It is hoped that the proposed theoretical framework of this study can serve as a crucial guideline for the development of environmental communication studies, especially among the media and ENGOs not only in Malaysia but also in other (Southeast) Asian regions that share a similar background.
Using panel data from Spain Farinas and Ruano (IJIO 2005) test three hypotheses from a model by Hopenhayn (Econometrica 1992): (H1) Firms that exit in year t were in t-1 less productive than firms that continue to produce in t. (H2) Firms that enter in year t are less productive than incumbent firms in year t. (H3) Surviving firms from an entry cohort were more productive than non-surviving firms from this cohort in the start year. Results for Spain support all three hypotheses. This paper replicates the study using a unique newly available panel data sets for all manufacturing plants from Germany (1995 – 2002). Again, all three hypotheses are supported empirically.
Entrepreneurship is an important means for economic development and poverty alleviation . Due to the relevance of entrepreneurship, scholars call for research that contributes to the understanding of successful business creation. In order to best understand new venture creation, research needs to investigate barriers of entrepreneurship. A barrier that has received wide attention in the literature on new venture creation is capital requirements. Scholars argue that capital requirements are an entry barrier for new venture creation, as most people who start businesses have difficulties in acquiring the necessary amount of capital needed for starting the businesses. Particularly in developing countries, scholars and practitioners regard improvements in access to capital as a major solution to support new venture creation. However, besides improving access to capital, there are alternative solutions that help to deal with the problems of capital requirements and capital constraints in the process of new venture creation. In this dissertation, I argue that a possible means to master capital requirements and capital constraints in business creation is action-oriented entrepreneurship training. I draw on actionregulation theory (Frese & Zapf, 1994), theories supporting an interactionist approach (Endler & Edwards, 1986; Terborg, 1981) and on theories about career development (Arthur, 1994; Briscoe & Hall, 2006) to reason that action-oriented entrepreneurship training allows for handling capital requirements and capital constraints with regard to business creation. Specifically, I argue that action-oriented entrepreneurship training helps to deal with financial requirements and capital constraints in two ways: First, the training reduces the negative effect of capital constraints on business creation through the development of financial mental models. Second, the training supports finding employment and receiving employment income, which enable businesses creation.
This dissertation deals with the investigation of success factors in the field of entrepreneurship, especially entrepreneurship training, from a psychological perspective. In particular, I argue that the identification of certain psychological aspects helps to better understand the underlying mechanisms for successful entrepreneurship trainings and thus, enables successful entrepreneurship. In the second chapter I theoretically examined planning as a fundamental action an entrepreneur hast to undertake in order to succeed. Scholars are in disagreement about the question if planning is crucial for the entrepreneurship. Thus, I provide a comprehensive overview of the advantages and disadvantages of planning in entrepreneurship from a psychological perspective. I explain negative aspects (e.g., lack of knowledge, difficulty to predict the future, and inflexibility) as well as positive aspects (e.g., legitimating, action-regulatory, and learning function) about planning in entrepreneurship. Furthermore, I develop a theoretical model that combines both the positive and negative aspects of planning in entrepreneurship. With this theoretical model, I integrate different types of planning (e.g., formal and informal plans) as well as positive and negative functions of planning (e.g., learning or stickiness, inflexibility) to provide a first approximation for a theory of entrepreneurial planning. In the third chapter, to focus on the field of entrepreneurial trainings, I empirically examine the under-researched field of the relation between trainer and trainee. I use the transformational leadership theory (Bass, 1985) and a theory of learning outcome (Kraiger, Ford, & Salas, 1993), to hypothesize that the trainers´ charisma has a positive effect on the trainees´ entrepreneurial self-efficacy. Additionally, I search for possible moderators for the hypothesized trainer-trainee-relationship in an explorative manner, using insight from different research areas (e.g., pedagogy, philosophy). To test the hypotheses, I conducted a 12-week entrepreneurship training by which I had 12 measurement waves across four classes with 161 students and 12 trainers, which lead to 919 observations. In the fourth chapter, to broaden the perspective on the mechanisms within entrepreneurship training, which lead to a successful outcome, I empirically examined the short- and long-term effects of entrepreneurship training on life satisfaction. To do so, I developed a theoretical model based on theories of life satisfaction, that explain the underlying mechanisms of the short- and long-term effects of the entrepreneurship training on life satisfaction. With this model I hypothesize, that entrepreneurship training has a positive short- effect on life satisfaction, which is mediated through entrepreneurial self-efficacy. I furthermore hypothesize, that the long-term effect of the entrepreneurship training is mediated through self-employment. The short term-effect acts like a boost and vanishes over time, whereas the long-term effect holds in the long run. To test these hypotheses, I conducted entrepreneurship training as part of a randomized controlled field experiment with five measurement waves over a total period of 2.5 years. Using discontinuous growth modeling to take into account the temporality of our hypothesized effects we statistically analyzed the 1,092 observations from 312 students. Chapter 5 concludes this dissertation with general discussion of the three chapters.
Entrepreneurs and Freelancers: Are They Time and Income Multidimensional Poor? - The German Case
(2016)
Entrepreneurs and freelancers, the self-employed, commonly are characterized as not only to be relatively rich in income but also as to be rich in time because of their time-sovereignty in principle. Our introducing study scrutinises these results and notions about the well-being situation of self-employed persons not only by asking about traditional single income poverty but also by considering time poverty within the framework of a new interdependent multidimensional (IMD) poverty concept. The German Socio-economic panel with satisfaction data serves as the data base for the population wide evaluation of the substitution/compensation between genuine, personal leisure time and income. The available detailed Time Use Surveys of 1991/92 and 2001/2 of the Federal Statistics Office provide the data to quantify the multidimensional poverty in all the IMD poverty regimes. Important result: self-employed with regard to single income poverty, single time poverty and interdependent multidimensional time and income poverty in both years are much more affected by time and income poverty than all other active persons defining the working poor. A significant proportion of non-income-poor but time poor of the active population are not able to compensate their time deficit even by an above poverty income. These people are neglected so far within the poverty and well-being discussion, the discussion about the ´working poor´ and in the discussion about time squeeze and time pressure in general and in particular for the self-employed as entrepreneurs and freelancers.
Human activities have become a major driver of global change, so that global society and economy are facing consequences such as climate change, increasing scarcity of resources, environmental pollution and degradation as well as disturbances of ecosystem functioning and services.In order to meet these main challenges in an appropriate way, adequate starting points and solutions must be pursued at all levels to shift the current socio-economic pathway from an unsustainable to a safe operating and thus sustainable development within the planetary boundaries. One of the application concepts in industrial contexts is Industrial Symbiosis (IS), which deals with the set-up of advanced circular/cascading systems, in which the energy and material flows are prolonged for multiple material and energetic (re-)utilization within industrial systems in order to increase resource productivity and efficiency, while reducing environmental impacts. The overarching goal of the research project was to identify and develop approaches to enable the evolution of Industrial Symbiosis (IS) in Industrial Parks (IPs). IS is a collaborative cross-sectoral approach to connect the resource supply and demand of various industries in order to optimize the resource use through exchange of materials, energy, water and human resources across different companies, while generating ecological, technical, social and economic benefits. Many Information Communication Technology (ICT) tools have been developed to facilitate IS, but they predominantly focus on the as-is analysis of the IS system, and do not consider the development of a common desired target vision or corresponding possible future scenarios as well as conceivable transformation paths from the actual to the defined (sustainability) target state. This gap shall be addressed in this work, presenting the software requirements engineering results for a holistic IT-supported IS tool covering system analysis, transformation simulation and goal-setting. This study also aims to present the conceptual IT-supported IS tool and its corresponding prototype, developed for the identification of IS opportunities in IPs. This IS tool serves as an IS facilitating platform, providing transparency among market players and proposing potential cooperation partners according to selectable criteria (e.g. geographical radius, material properties, material quality, purchase quantity, delivery period). Therefore a quantitative indicator system was compiled and recurring patterns were identified to utilize this knowledge in the comprehensive IT-supported IS tool. So this IS tool builds the technology-enabled environment for the processes of first screening of IS possibilities and initiation for further complex business-driven negotiations and agreements for long-term IS business relationships.
Since 2000, data generation has been growing rapidly from various sources, such as Internet usage, mobile devices and industrial sensors in manufacturing. As of 2011, these sources were responsible for a 1.4-fold annual data growth. This development influences practice and science equally and led to different notations, one of the most popular one is Big Data. Besides organization with a business model based solely on Big Data, companies have started to implement new technologies, methodologies and processes in order to deal with the influx of data from different sources and structures and benefit the most of it. As the progress of the implementation and the degree of professionalism regarding data analysis differs amongst industries and companies, latter ones are faced with a lack of orientation regarding their own stage of development and existing relevant capabilities in order to deal with the influx of data as only a few best practices exist. Therefore, this research project develops a maturity model for the assessment of companies capabilities in the field of data analysis with a focus on Big Data. Basis for the model development is a construction model, developed along the criteria of Design Science Research. The developed model contains the different levels of maturity and related measurements for the evaluation of a companies Big Data capabilities with a focus on topics along the dimensions data and organization. The developed model has been evaluated based an application to different companies in order to ensure the practical relevance. The structure of the thesis is the following: In a first step, a structured literature review is carried out, focussing on existing maturity models in the field of Big Data and nearby fields as Business Intelligence and Performance Management Systems. Based on the identified white spots, a design science research oriented construction model for the maturity model development is designed. This model is applied subsequently.
This dissertation evaluated the efficacy of three different internet-based interventions that can be regarded as indirect interventions to reduce depression since they primarily targeted risk factors for depression. For this purpose three registered randomized controlled trials were conducted. In addition to assessing the efficacy of the interventions regarding the primary outcomes, the efficacy to reduce depression and further secondary outcomes was studied. In Study I (N=200) the efficacy of an internet-based stress management intervention (iSMI), which was adapted and tailored to career starting teachers, was compared to a waitlist control group (WLG). The participants of the intervention group (IG) reported significant reductions on the primary outcome perceived stress at post-intervention (T2) and three month follow-up (3-MFU). Furthermore, it was shown that the intervention indirectly also reduced depression at T2 and 3-MFU. The effects were sustained at an extended 6-MFU. Besides efficacy, the feasibility to complement the iSMI with a newly developed internet-based classroom management training was shown. Moreover, mediation analyses corroborated the role of problem- and emotion-focused coping skills in the intervention's effect on stress and the indirect effect of the intervention on depression through stress. Study II (N=262) demonstrated the efficacy of an internet- and app-based gratitude intervention on the reduction of primary assessed repetitive negative thoughts at T2 and 3-MFU, as compared to a WLG. The participants of the IG also reported significantly reduced depressive symptoms at T2, and 3-MFU, with significant clinically meaningful effects. The effects were sustained at an extended 6-MFU. Besides efficacy, mediation analyses showed that repetitive negative thinking mediated the gratitude intervention's effect on depression. Finally, Study III N(=351) showed that an internet-based intervention, tackling worries at the beginning of the COVID-19 pandemic, was effective as compared to an active mental health advice group. At T2, two weeks after randomization, the IG reported significantly reduced levels on the primary outcome worry as compared to controls. Participants of the IG also reported significantly reduced levels of depression at T2, with significant clinically meaningful reductions. The extended follow-ups in the IG indicated that the improvements from baseline were sustained until the 2-MFU and the 6-MFU. In a mediation analysis, worry was shown to mediate the intervention's effect on depression. Across all three studies a reliable deterioration of depression was occasionally observed. In summary, the studies in this dissertation demonstrated the efficacy of various indirect interventions focusing on rather common psychological problems to indirectly reduce depressive symptoms. The extent to which depression severity could be reduced is comparable to reductions found within participants with comparable baseline depression severity, in internet-based interventions directly addressing depressive symptoms. Indirect interventions are suggested to increase the uptake of interventions that reduce depressive symptoms, since they might be perceived as less stigmatizing and might broaden the range of interventions to choose from.
Biodiversity loss could jeopardize ecosystem functioning. Yet, the evidences that support this demonstration have been mostly obtained in aquatic and grassland ecosystems. Howbiodiversity affects ecosystem functioning still remain largely unanswered in forests, particularly in subtropical broad-leaved evergreen forests (EBLF). Tree productivity, among a wealth of forest ecosystem functioning, is of particular interest because it reflects the carbon sink capacity and wood productivity. Biodiversity-productivity relationships have been usually investigated at community level. However, tree-tree interactions occur at small scale. Thus, local neighborhood approach may allow a better understanding of tree-tree interactions and their contributions to the effects of biodiversity on tree productivity / growth rates. This thesis aims to analyze the effects of biodiversity and the abiotic environmental factors on the tree growth rates using both local neighborhood and community-based approaches. Furthermore, tree growth rates vary among different tree species. Functional traits have been related to the species-specific growth rates to understand the effects of species identity. Therefore, I also evaluated the crown- and leaf traits to predict the interspecific difference in growth rates. For a better understanding of the mechanisms that underline the relationships of biodiversity and tree growth rates, data of high solution and along time series is required to scrutinize the tree-tree interactions. Thereupon, I evaluated the applicability of terrestrial laser scanning (TLS) in assessing the tree dendrometrics. This thesis was conducted in the Biodiversity Ecosystem Functioning (BEF)–China experiment, which is located in a mountainous subtropical region in southeast China. A total of 40 native broad-leaved tree species were planted. In the first study, I used the local neighborhood approach to analyze how local abiotic conditions (i.e. topographic and edaphic conditions) and local neighborhood (i.e. species diversity and competition by neighborhood) affect the annual growth rates of 6723 individual trees. The second study used the community approach to partition the effects of environmental factors (i.e. topographic and edaphic), functional diversity according to Rao’s quadratic entropy (FDQ) and community weight mean (CWM) of 41 functional traits on community tree growth rates. The main question of the third study was how the species-specific growth rates are related to five crown- and 12 leaf traits.
In the fourth study, I investigated 438 tree individuals for the congruence between the conventional direct field measurements and TLS measurements. It was found that tree growth rates were strongly influenced by the local topographic and edaphic conditions but not affected by the diversity of local neighborhood. In contrast, results obtained by using the community-based approach showed that FDQ and CWMs of various leaf traits rather than abiotic environmental factors had significant impact on the community means of growth rates. Tree-tree interactions already occur in early life stages of trees, which were evidenced by the significant effect of competition by local neighborhood. These findings imply that the effects of abiotic environmental factors may be more evident at local scale and biodiversity effects may vary at different spatial scales. The species-specific growth rates were found to be related to specific leaf traits but not to crown traits and were best explained by both types of traits in combination. This finding supports the niche theory and provides the evidence for using functional diversity to examine the BEF relationships. The TLS-retrieved total tree height, stem diameter at 5 cm above ground, and length and height of the longest branch were highly congruent with those obtained from direct measurements. It indicates that TLS is a promising tool for high resolution, non-destructive analyses of tree structures in young tree plantations. Being one of very few studies to incorporate the individual tree scale in examining the biodiversity-productivity relationships within the BEF researches, this thesis stresses the importance of using individual-tree based approach, functional diversity and TLS to find the evidences of explanatory mechanisms of the observed biodiversity and ecosystem functioning (e.g. tree growth rates) relationships. Biodiversity effects may evolve along the successional stages. Therefore, incorporating the interaction between biodiversity and time in analyzing BEF relationship is also encouraged.
In my dissertation I explore conceptual and economic aspects of resilience, i.e. a system’s ability to maintain its basic functions and controls under disturbances. I provide methodological considerations on the conceptual level and general insights derived from stylized ecological-economic models. In doing so, I demonstrate how to frame resilience so as to economically evaluate and investigate it as an important property of ecological-economic systems. Is conceptual vagueness an asset or a liability? In chapter 1 I address this question by weighing arguments from philosophy of science and applying them to the concept of resilience. I first sketch the wide spectrum of resilience concepts that ranges from concise concepts to the vague perspective of “resilience thinking”. Subsequently, I set out the methodological arguments in favor and against conceptual vagueness. While traditional philosophy of science emphasizes precision and conceptual clarity as precondition for empirical science, alternative views highlight vagueness as fuel for creative and pragmatic problem-solving. Reviewing this discussion, I argue that a trade-off between vagueness and precision exists, which is to be solved differently depending on the research context. In some contexts research benefits from conceptual vagueness while in others it depends on precision. Assessing the specific example of “resilience thinking” in detail, I propose a restructuring of the conceptual framework which explicitly distinguishes descriptive and normative knowledge. Chapter 2 investigates the common assumption that the optimization problem within a simple selfprotection problem (spp) is convex. It is shown that the condition given in the literature to legitimate this assumption may have implausible consequences. Via a simple functional specification we analyze the (non-)convexity of the spp more thoroughly and find that for reasonable parameter values strict convexity may not be justified. In particular, we demonstrate numerically that full self-protection is often optimal. Neglecting these boundary solutions and analyzing only the comparative statics of interior maxima may entail misleading policy implications such as underinvestment in self-protection. Thus, we highlight the relevance of full self-protection as a policy option even for non-extreme losses. Chapter 3 starts from the observation that ecosystem resilience is often interpreted as insurance: by decreasing the probability of future drops in the provision of ecosystem services, resilience insures risk-averse ecosystem users against potential welfare losses. Using a general and stringent definition of “insurance” and a simple ecological-economic model, we derive the economic insurance value of ecosystem resilience and study how it depends on ecosystem properties, economic context, and the ecosystem user’s risk preferences. We show that (i) the insurance value of resilience is negative (positive) for low (high) levels of resilience, (ii) it increases with the level of resilience, and (iii) it is one additive component of the total economic value of resilience. Chapter 4 performs a model analysis to study the origins of limited resilience in coupled ecologicaleconomic systems. We demonstrate that under open access to ecosystems for profit-maximizing harvesting forms, the resilience properties of the system are essentially determined by consumer preferences for ecosystem services. In particular, we show that complementarity and relative importance of ecosystem services in consumption may significantly decrease the resilience of (almost) any given state of the system. We conclude that the role of consumer preferences and management institutions is not just to facilitate adaptation to, or transformation of, some natural dynamics of ecosystems. Rather, consumer preferences and management institutions are themselves important determinants of the fundamental dynamic characteristics of coupled ecological-economic systems, such as limited resilience. Chapter 5 describes how real option techniques and resilience thinking can be integrated to better understand and inform decision making around environmental risks within complex systems. Resilience thinking offers a promising framework for framing environmental risks posed through the non-linear responses of complex systems to natural and human-induced disturbance pressures. Real options techniques offer the potential to directly model such systems including consideration of the prospect that the passage of time opens new options while closing others. Examples are provided which illustrate the potential for integrated resilience and real options approaches to contribute to understanding and managing environmental risk.
In the course of railway reforms at the end of the last century, European national governments, as well the EU Commission, decided to open markets and to separate railway networks from train operations. Vertically integrated railway companies argue that such a separation of infrastructure and operations would diminish the advantages of vertical integration and would therefore not be suitable to raise economic welfare. In this paper, we conduct a pan-European analysis to investigate the performance of European railways with a particular focus on economies of scope associated with vertical integration. We test the hypothesis that integrated railways realize economies of joint production and, thus, produce railway services on a higher level of e±ciency. To determine whether joint or separate production is more e±cient we apply an innovative Data Envelopment Analysis super-e±ciency bootstrapping model which relates the e±ciency for integrated production to a virtual reference set consisting of the separated production technology and which is applicable to other network industries as energy and telecommunication as well. Our ¯ndings are that for a majority of European Railway companies economies of scope exist.
In addition to a short introduction, this thesis contains five chapters that discuss various topics in the context of labor economics in general and the manufacturing sector in Egypt in particular. Chapter one presents the institutional framework of the Egyptian labor market and the different datasets that could be used by researchers and summarizes some previous empirical studies. Then, different microeconometric methods are applied in the subsequent four chapters, using the World Bank firm-level data for the manufacturing sector in Egypt to get an empirical evidence for the following issues: determinants of using fixed-term contracts in the Egyptian labor market in the manufacturing sector in chapter two, determinants of female employment in Egyptian manufacturing firms in chapter three, ownership structure and productivity in the Egyptian manufacturing firms in chapter four and, finally, exporting behavior of the Egyptian manufacturing firms is analyzed with a special focus on the impact of workforce skills-intensity in chapter five.
Strong sustainability, according to the common definition, requires that different natural and economic capital stocks have to be maintained as physical quantities separately. Yet, in a world of uncertainty this cannot be guaranteed. To therefore define strong sustainability under uncertainty in an operational manner, we propose to use the concept of viability. Viability means that the different components and functions of a dynamic, stochastic system at any time remain in a domain where the future existence of these components and functions is guaranteed with sufficiently high probability. We develop a unifying and general ecological-economic concept of viability that encompasses the traditional ecological and economic notions of viability as special cases. It provides an operational criterion of strong sustainability under conditions of uncertainty. We illustrate this concept and demonstrate its usefulness by applying it to livestock grazing management in semi-arid rangelands.
The paper demonstrates how the E–stability principle introduced by Evans and Honkapohja can be applied to models with heterogeneous and private information in order to assess the stability of rational expectations equilibria under learning. The paper extends already known stability results for the Grossman and Stiglitz model to a more general case with many differentially informed agents and to the case where information is endogenously acquired by optimizing agents. In both cases it turns out that the rational expectations equilibrium of the model is inherently E-stable and thus locally stable under recursive least squares learning.
Both practitioners and researchers alike assign considerable importance to innovation. However, the process of how innovation unfolds over time is still not well understood. It is the aim of this dissertation to introduce an elaborated picture of innovation processes over time and to discuss the implications of the dynamics of the innovation process for individuals working in innovative contexts, that is, leaders and team members of innovative teams. The first paper of lays the theoretical and empirical groundwork of my dissertation in demonstrating that within the boundaries of the gradual development of innovation activities over time innovation processes are recursive and highly dynamic. These dynamics make the innovation process a challenge for everyone involved in it. In the second and third paper of my dissertation, I discuss this challenge in greater detail for leaders and team members of innovative work teams. Thus, with this dissertation I do not only to give a more elaborate picture of how innovation projects unfold over time, but also describe the challenges attached to the innovation process and give first answers to the question of how individuals involved in this process may be able to master these challenges.
Do exporters really pay higher wages? First evidence from German linked employer-employee data
(2006)
Many plant-level studies find that average wages in exporting firms are higher than in non-exporting firms from the same industry and region. This paper uses a large set of linked employer-employee data from Germany to analyze this exporter wage premium. We show that the wage differential becomes smaller but does not completely vanish when observable and unobservable characteristics of the employees and of the work place are controlled for. For example, blue-collar (white-collar) employees working in a plant with an export-sales ratio of 60 percent earn about 1.8 (0.9) percent more than similar employees in otherwise identical non-exporting plants.
This thesis gives an overview on the diversity of some beetle species in different Mediterranean habitats as well as on the influence of forest management on insect diversity. Primarily, this work involved fundamental research, because very little research had previously been conducted under biodiversity aspects on either ground beetles or saproxylic beetles in the Mediterranean area of Israel. It was possible to prove that stenotopic ground beetles occur in different habitat types. Furthermore, the results of Chapter I and Chapter III show that additional research is needed to obtain a clear view of the beetle diversity in this area. Future studies should consider that a variety of catching methods are needed throughout the annual cycle in order to catch a good spectrum of ground beetles living in these habitats. It is clearly not sufficient to conduct a study of ground beetles using only pitfall traps and/or to restrict the study to the wet winter months. The conclusions and management recommendations are therefore as follows: More studies on insect biodiversity are needed to obtain a comprehensive overview of insects in natural and planted Mediterranean woodlands. To facilitate this for a wide spectrum of scientists, identification keys for the Mediterranean insect fauna are urgently needed. Furthermore, foresters are in a position to decide which tree species composition has to be established and for what purpose. Nowadays, issues of forest management are primarily led by the objectives and potential uses of the forests. In times of global change, however, the potential future climatic situation and the ecosystem services provided by different woodlands also have to be considered when planning forest management (cf. also DUFOUR-DROR 2005 for Israel). Forest management is therefore also a matter of regional development and must thus include social demands and conservation actions. In a recent paper, OSEM et al. (2008) propose that forest management should consider different objectives, e.g. forests as a provider of ecosystem services, such as water infiltration, carbon sequestration and biodiversity. For these reasons, foresters should take the opportunity to establish oak individuals as a woody understorey component in pine stands. This would not only increase forest diversity but also strengthen the forests’ resistance and resilience to pest outbreaks, and would ensure better ecosystem functioning and soil stabilisation (cf. GINSBERG 2006; OSEM et al. 2008; PAUSAS et al., 2004). Moreover, both old and recent woodlands provide unique sections of biodiversity, as revealed by the occurrence of species restricted to specific microhabitats. However, not only forest management but the management of all natural or semi-natural habitats in northern Israel is important. Many, if not all of these habitats, have been severely affected or completely destroyed by urban, industrial and agricultural development and fragmentation or by dense afforestation with non-native trees (e.g. Eucalyptus). This development, especially the loss of open space, is continuing because of Israel’s high human population density. For these reasons, all natural or semi-natural habitats are endangered (YOM-TOV & MENDELSSOHN 2004). This alarming development is in contrast with the overall importance of the region as a biodiversity hotspot (YOM-TOV and TCHERNOV 1988). This thesis demonstrates that there are numerous (also stenotopic) beetle species with preferences to specific habitats of open space (e.g. old-growth oak woodlands, recent oak woodlands, pine plantations, batha and old oak tree individuals). If Israel’s beetle diversity is to be preserved in future, it will be vital to protect all habitats and their succession stages.
Establishing the identity of asylum seekers in the absence of credible documents represents a significant challenge for governments. To support decision-making processes in identity determination and verification procedures, Germany’s Federal Office for Migration and Refugees introduced three digital identification systems under the “Integrated Identity Management - plausibility, data quality and security aspects (IDMS)” programme. Because these algorithmic systems are deployed in highly political settings affecting vulnerable populations on the move, this research investigates how the Federal Office legitimises the policy and use of IDM-S that indicate a new direction of governance driven by so-called “innovative technologies”. In this context, legitimacy - considered a core virtue of just, democratic institutions - is understood as a justificatory concept seen in conjunction with (good) governance and the right to privacy as guaranteed under Article 17 of the International Covenant on Civil and Political Rights. The data justice framework is applied to structure the evaluation of state practices. In addition, the qualitative content analysis is used to find patterns in publicly available documents. Expert interviews were carried out to include experiences of affected individuals and to verify identified information provided by the government. The analysis revealed that efforts to legitimise IDM-S included four patterns: referring to the rule of law and national security concerns, non-disclosing delegitimising information and limiting accountability, emphasising performance efficiency and the systems’ high level of innovation, implying objective operations by means of a mathematical-technical approach. The results underscore profound discrepancies between justifications and state practices, outlining severe privacy violations as well as the lack of compliance to qualitative values in governance that pertain to participation, transparency, accountability, impartiality and scientific soundness of state operations.
This paper uses data from the German Socio-Economic Panel for the years 2000 to 2005 to study the earnings differential between self- and dependent employed German men. Constructing a counterfactual earnings distribution for the self-employed in dependent employment and using quantile regression decompositions we find that the earnings differential over the distribution cannot be explained by differences in endowments. Furthermore, low-earning self-employed could earn more in dependent employment. Finally, the observed earnings advantage for the self-employed at the top of the earnings distribution is not associated with higher returns to observable variables.
The research described in this dissertation focuses on developing a process to remove oligomers and suppress their formation by intercepting the aging procedure's precursors using adsorbents when biodiesel and its blends are used as fuel. So far, there has been no attempt to cause the stabilization of biodiesel and its blends using adsorbents from open literature. This investigation is one of the first studies on the use of adsorbents to mitigate biodiesel and diesel fuel's stability behavior–biodiesel blends and the removal of oligomers or suppressing the formation of high molecular mass species in aging oil. This study's primary aim has been achieved by several experimental measurements that provided results on adsorbents' effecton fuel oxidative stability, especially ester-based fuel like biodiesel and its blends. The chemical composition and some critical rheological analyses of the samples have been measured to understand their role in the oxidation of the sample by comparing the presence and absence of the adsorbents during the aging process. Furthermore, it aims to use adsorbents to suppress oligomers' formation and remove them in aging oil due to the influence of biodiesel and its blends. The research project also seeks to stabilize fuel, especially ester-based fuel like biodiesel, and its blends using the adsorbents. The adsorbents' application will enhance biodiesel's oxidative stability and its blends during long-term storage or application, focusing on its use in plug-in hybrid vehicles, emergency power plants,and generators. The combustion engine only starts in plug-in hybrid vehicles if the battery cannot supply energy on longer journeys. As a result, the fuel remains longer in plug-in hybrid vehicles. Fuels that are exposed to heat and oxygen over anextendedperiod can form aging products. These aging products lead to the formation of deposits, especially in the case of diesel fuels mixed with biodiesel content,and can, therefore, endanger the operational safety of the vehicle in critical components such as injectors or filter units.
Air quality models are important tools which are utilized for a large field of application. When combined with data from observations, models can be employed to create a comprehensive estimation of the past and current distribution of pollutants in the atmosphere. Moreover, projections of future concentration changes due to changing emissions serve as an important decision basis for policymakers. For the determination of atmospheric concentrations of air pollutants by means of numerical modelling it is essential to possess a model which is able to create anthropogenic and biogenic emissions with a temporally and spatially high resolution. The emission data is needed as input for a chemistry transport model which calculates transport, deposition, and degradation of air pollutants. To evaluate the impact of changing emissions on the environment a flexible emission model with the capability to create diverse emission scenarios is needed. Further, it is important to always take into account a variety of different species to properly represent the major chemical reactions in the atmosphere (e.g. ozone chemistry, aerosol formation). Currently there are only a few high resolution emission datasets available for Europe. The amount of substances included in these datasets, however, is limited. Moreover, they can not be used as basis for the creation of new emission scenarios. To enable the creation of emission scenarios in the course of this doctoral thesis the American emission model SMOKE was adopted and modified. On the basis of a multitude of different georeferenced datasets, official statistics, and further model results the newly created emission model “SMOKE for Europe” is capable of creating hourly emission data for the European continent with a spatial resolution of up to 5x5km2. In order to demonstrate the universal applicability of the emission model the carcinogenic species benzo[a]pyrene (BaP) was exemplarily implemented into the model. BaP belongs to the group of polycyclic aromatic hydrocarbons. Because of its high toxicity the European Union introduced an annual target value of 1 ng/m3 in January 2010. SMOKE for Europe was used to create a variety of emission scenarios for the years 1980, 2000, and 2020. These emission scenarios were then used to determine the impact of emission changes on atmospheric concentrations of BaP and to identify regions which exceed the European target value. Additionally the impact of different legislation and fuel use scenarios on the projected atmospheric concentrations in 2020 was investigated. Furthermore, additional use cases for a flexible emission model are pointed out. The SMOKE for Europe model was used to simulate the transport of volcanic ash after the eruption of the Icelandic volcano Eyjafjallajokull in March 2010. By comparison of modelled concentrations for different emission scenarios with observations from remote sensing and air plane flights distribution and concentration of the volcanic ash over Europe was estimated. The results of this thesis have been presented in four scientific papers published in international peerreviewed journals. The papers are reprinted at the end of this thesis.
Panic disorder is a common anxiety disorder, which is associated with high subjective burden as well as a high cost for the health economy. According to the National Treatment Guideline S3, cognitive behavior therapy is recommended as the most effective psychological treatment. However, many people in need do not have access to cognitive behavior therapy. Internet-based interventions have proven to be an effective way to provide access to evidence-based treatment to those affected. For anxiety disorders, such as panic disorder and agoraphobia, a good effectiveness of internet-based interventions has been proven in numerous international studies. However, the internet has changed over the last few years: mobile technologies have considerable potential to further improve the adherence and effectiveness of internet-based interventions. Against this background, the authors developed the hybrid online training "GET.ON Panic". In this training, an app has been integrated into a browser-based online training. The app consists of a mobile diary for self-monitoring as well as a mobile exposure-guide that supports participants in self-exposure exercises in their everyday lives.In an initial exploratory feasibility study, qualitative interview data and quantitative measurements were collected in a pre-post design of 10 participants. Usage, user friendliness, user satisfaction and acceptance of the app were generally considered high. The use of interoceptive exposure exercises and daily summaries of anxiety and mood were the most widely performed and rated the best, while in vivo exposure exercises and the monitoring of acute panic symptoms were found to be difficult.In the efficacy study, 92 participants with mild to moderate panic symptoms were randomized into two parallel groups. After eight weeks, the intervention group showed a significant improvement in the severity of panic symptoms compared to the waiting control group. Using the intention-to-treat approach, a covariance analysis with baseline values as a covariate yielded a mean effect of Cohen's d=0.66 in reducing the panic symptoms in favor of the intervention group. This effect increased to d=0.89 after three months and stayed at d=0.81 at the 6-month measurement point. Response and remission rates were also significantly higher in the intervention group. This positive effect was also shown for secondary outcomes such as depressive symptoms and quality of life. A correlation between app usage and clinical outcomes could not be found. This work was the first to demonstrate that a hybrid online training based on cognitive behavior therapy is effective in reducing panic symptoms as well as panic disorder. In addition, this work contributes to a deeper understanding of the potential of mobile technologies in the field of e-mental health.
Thermal energy storage systems have a high potential for a sustainable energy management. Low temperature thermochemical energy stores based on gas-solid reactions represent appealing alternative options to sensible and latent storage technologies, in particular for heating and cooling purposes. They convert heat energy provided from renewable energy and waste heat sources into chemical energy and can effectively contribute to load balancing and CO2 mitigation. At present, several obstacles are associated with the implementation in full-scale reactors. Notably, the mass and heat transfer must be optimized. Limitations in the heat transport and diffusions resistances are mainly related to physical stability issues, adsorption/desorption hysteresis and volume expansion and can impact the reversibility of gas-solid reactions. The aim of this thesis was to examine the energy storage and cooling efficiency of CaCl2, MgCl2, and their physical salt mixtures as adsorbents paired with water, ethanol and methanol as adsorbates for utilization in a closed, low level energy store. Two-component composite adsorbents were engineered using a representative set of different host matrices (activated carbon, binderless zeolite NaX, expanded natural graphite, expanded vermiculite, natural clinoptiolite, and silica gel). The energetic characteristics and sorption behavior of the parent salts and modified thermochemical materials were analyzed employing TGA/DSC, TG-MS, Raman spectroscopy, and XRD. Successive discharging/charging cycles were conducted to determine the cycle stability of the storage materials. The overall performance was strongly dependent on the material combination. Increase in the partial pressure of the adsorbate accelerated the overall adsorbate uptake. From energetic perspectives the CaCl2-H2O system exhibited higher energy storage densities than the CaCl2 and MgCl2 alcoholates studied. The latter were prone to irreversible decomposition. Ethyl chloride formation was observed for MgCl2 at room and elevated temperatures. TG-MS measurements confirmed the evolution of alkyl chloride from MgCl2 ethanolates and methanolates upon heating. However, CaCl2 and its ethanolates and methanolates proved reversible and cyclable in the temperature range between 25°C and 500°C. All composite adsorbents achieved intermediate energy storage densities between the salt and the matrix. The use of carbonaceous matrices had a heat and mass transfer promoting effect on the reaction system CaCl2-H2O. Expanded graphite affected only moderately the adsorption/desorption of methanol onto CaCl2. CaCl2 dispersed inside zeolite 13X showed excellent adsorption kinetics towards ethanol. However, main drawback of the molecular sieve used as supporting structure was the apparent high charging temperature. Despite variations in the reactivity over thermal cycling caused by structural deterioration, composite adsorbents based on CaCl2 have a good potential as thermochemical energy storage materials for heating and cooling applications. Further research is required so that the storage media tested can meet all necessary technical requirements.
Food forests present a promising solution to address multiple sustainability challenges adaptable to local contexts. As biodiverse multi-strata agroforestry systems, they can provide several ecological, socio-cultural and economic services. They sequester carbon, limit soil erosion and regulate the micro-climate; they offer the opportunity for education on healthy diets and ecology, and they produce food and can create livelihood opportunities. However, despite their obvious benefits, food forests are still a niche concept. To date, research has focused on their ecological and social services; we lack an understanding of food forests as a comprehensive sustainability solution, including their economic dimension, and knowledge on how to develop them. Addressing these gaps, this qualitative research used a solution- and process-oriented methodology guided by transformational sustainability research. In a comparative case study approach, it created an inventory of 209 food forests, followed by interviews and site visits of 14 sites to understand their characteristics and assess their sustainability (Article 1). More indepth, it analyzed the implementation path of seven food forest for success factors, barriers and coping strategies (Article 2). Based on these insights, two experimental case studies were initiated to develop sustainable food forests with practice partners, one based in Phoenix, Arizona, U.S. and one in Lüneburg, Germany. Two studies analyzed the cases' outputs and processes highlighting success factors and challenges, including the role of a sustainable entrepreneurial ecosystem (Article 3, Phoenix case) and key features of productive partnerships to understand why one case succeeded and the other failed (Article 4). Findings include key features of existing and sustainable food forests as well as success factors on how to develop them; namely acquiring a complementary skill set that includes specialty farming and entrepreneurial know-how, securing sufficient start-up funds and long-term land access as well as overcoming regulatory restrictions. Supporting institutions are especially needed to integrate and professionalize the planning stage and provide know-how on alternative business practices. Key features of productive partnerships include an entrepreneurial attitude, access to support functions, long-term orientation and commitment to food system sustainability.