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Increased international compliance with human rights and democracy standards is a core issue for both human rights and democratizing actors as well as for victims of human rights abuse. International human rights organizations (IHROs) are expected to make positive contributions to this end, even though they possess low levels of authority. This authority has been renegotiated multiple times in various reform processes. An oversimplified expectation would have us assume that democracies would want to strengthen IHROs, and that autocracies would seek to weaken them. As the United Nations Human Rights Council (UNHRC) was reformed in 2006, 2007, 2010, and 2011, some autocracies strived to abolish parts of the UNHRC. Other autocracies aimed "merely" to weaken them. Democracies displayed an even larger variance. The question that drives this research work is how we can explain the broad variety of state preferences for strengthening or weakening IHROs. Previous research has mostly concentrated on democracies, leaving autocracies understudied. It also treated countries as black boxes. To account for such shortcomings, first, the author systematically tests the relationship between the UNHRC and its authoritarian and democratic members by means of inferential statistics. Second, he analyzes a bottom-up process inherent to New Liberalism. It scrutinizes the role of domestic societal actors, domestic institutions, as well as pressures on the international stage. The results reveal that societal actors, along with the interplay of wealth and regime type in the international realm, figure as the most important predictors of delegation preferences voiced by autocracies and democracies during the reform of the monitoring bureaucracy Special Procedures of the UNHRC. Societal actors play a more important role in democracies than in autocracies. Institutionalized domestic oversight mechanisms help societal actors to conduct effective lobbying at the domestic level. Oversight mechanisms are more important than the rule of law and electoral institutions. Regarding international coalition building, authoritarian regimes turn out to be better organized than democracies. The author concludes that supporters of strong IHROs shall 1. empower domestic societal actors; 2. disrupt cohesive delegation preferences of authoritarian regimes; and 3. invest in independent domestic oversight mechanisms.oversight mechanisms.
The challenges of sustainable development have spurred the complexity of management reality, unveiling considerable risks and opportunities for companies. The past twenty years of development in management science and practice have refined the understanding of the linkages between corporate success and sustainability aspects of business. Nevertheless, numerous management tools and concepts have been criticised for failing to contribute to improved sustainability performance. Management accounting is an indispensable system for generating, preparing and providing information for recognising decision situations and informing decisions. Building on the relevance of information, sustainability accounting has received considerable attention in the past decade. Related research has emphasised the contribution of sustainability accounting to tackling sustainability challenges in specific settings. A systematic investigation of the role of sustainability accounting is virtually non-existent to date. To overcome this limitation and provide an insight into the practice of sustainability accounting and its role in sustainability management and ultimately in corporate success, this doctoral thesis approaches the question How does sustainability accounting contribute to improved information management and management control? The direct contribution is two-fold. First, a number of decision situations are explicated. Examples for such decision situations include utilising certain types of information for specific decisions, engaging various functions in different ways, etc. Making a decision within these decision situations was observed to contribute to achieving corporate goals. Second, the overarching view on the results reveals an interesting pattern. It is the existence of this pattern that supports the view that sustainability accounting can help companies in the pursuit of improved sustainability performance and (thereby) corporate success. The findings enable both practitioners and researchers gain an insight into how sustainability accounting can be deployed so that the company’s limited resources are focused on the crucial decisions in information management and management control. Subsequent recommendations are supported by up-to-date examples. The nature and the scope of the research constituting this doctoral thesis also highlight the path for future research to expand and refine the propositions made herein.
The issue under investigation in this study is to explore the drivers and suggest methods for environmental managers to integrate environmental issues in the top management strategic decision-making. In order to make the reading easy the whole study has been written following the principle of providing the minimum information to clarify the point under discussion, no more, no less. The conclusions, the analysis, the implications and the limitations are discussed on a chapter by chapter basis, making it easier for the reader to remember the issue under discussion. The closing chapter brings together the conclusions of each chapter of the study. The study is divided into two parts. Part I: Planning describes the planning and preparation for the research and consists of the following chapters: Chapter 1 provides an overview of the interest, relevance and importance of this study. Also it proposes, through the introduction of the relevant literature, an exact wording for the research problem and a framework for evaluating the effectiveness of each process step. Chapters 2 and 3 describe and justify the chosen framework that prompts managers during interviewing and organises the resulting contents in a way that will support effective decision making. This is the end of the planning part of the study and we now move into the action part where the case studies are explained in full. Part II: Intervention comprises the following chapters: Chapter 4 is where the action begins, the first phase of the process. This chapter discusses the reasons selection and participation in the research and the process for choosing a business unit. Chapter 5 details, justifies and discusses the choices of who to interview. It outlines how the interviews were conducted and summarises the resulting contents. In Chapter 6 the general issue of who to involve in interviews is explored further for the specific case of the environmental manager. The main objective is to discuss whether and why the environmental manager had more/less/different ideas from the rest of the management team. Chapter 7 deals with the first time that the people meet as a group. For this process step the choices were about how to display and generate discussion on the contents gathered during the interviews. Chapter 8 focuses on the environmental manager’s contribution to the objective Fine-tuning discussion. Chapter 9 describes the Indicator Building process and how this may be relevant for the environmental manager. Concluding Remarks wraps up the results and discusses the need for extending this research further.
Scaling Strategies of Social Entrepreneurship Organizations – an Actor-Motivation Perspective
(2014)
Despite their sometimes ingenious solutions, many social entrepreneurs fail to scale which is at odds with their overall objective of social change. Yet, though considered highly important in practice, scaling is still under-researched. Taking this imbalance as a starting point, my PhD thesis contributes to the social entrepreneurship literature by shedding new light on the role of the actor-motivation in scaling social ventures. Put together, papers 1-3 try to answer the general research questions of how do actors and their specific motivations, particularly the social entrepreneur, influence the scaling strategies (and success) of social ventures? Based on a brief review of the literature on scaling, I identify social franchising as a promising scaling strategy that requires more research. Here, paper 1 argues that the social mission of the involved actors can serve as an informal functional equivalent to formal contracts as well as a means to safeguard the local small group logic. Paper 2 discusses the effects of stewardship on social franchising coming to the conclusion that stewardship relationships may impede speed of and degree of scaling. Based on these insights, paper 3 more closely analyzes the motivations of social entrepreneurs in a post-founding stage. It empirically constructs a taxonomy of (social) entrepreneurs based on their motivations. To this end, paper 3 employs a three-step methodological approach that combines the inductive insights from 80 interviews with entrepreneurs with a statistical cluster analysis. Following, this paper then discusses contributions of and implications for scaling research as well as to social entrepreneurship, entrepreneurship, and management research.
Space-related science and technologies affect our daily life. Many countries have already formulated national space regulations to regulate their space activities. China, as one space-faring country, has obtained several achievements in space science and technologies. In recent years, Chinese private space companies have sprung up quickly, which requires a stable and foreseeable legal framework to ensure development. However, compared to the other space powers, China is the only one that has not enacted any formal national space laws. Against the background of strengthening the rule of law in China, research on China's domestic space legislation is valuable and significant. The purpose of this thesis is two-fold. First, to find the legal basis and necessity of national space legislation and to extract the basic content of the existing national space legislation, simultaneously, to identify the new developments in the content of other States´ legislative practices. Second, based on the study of national space legislation, to propose the essential content of China's space legislation.
This thesis has been designed to improve the understanding of the distribution pattern and transport mechanisms of alkylphenols and the phthalates in the coastal margins, especially the roles of the air-sea exchanges in these processes. Henry’s Law Constants (HLC) were determined for the diastereomeric mixture of NP and t- OP in artificial seawater over given temperature range using a dynamic equilibrium system. An analytical method has been developed for the simultaneous extraction and determination of trace tertiary octylphenol (t-OP), technical nonylphenol isomers (NP), nonylphenol monoethoxylate isomers (NP1EO) and the phthalates in the atmosphere and sea water using gas chromatography-mass spectrometry (GC-MS). The method was successfully applied to the determination of APs and the phthalates in the atmosphere and sea water samples collected from the North Sea. A decreasing concentration profile of NP, t-OP, NP1EO and the phthalates appeared as the distance from the coast increased to the central part of the North Sea. Air-sea exchanges of t-OP, NP, DBP, BBP, and DEHP were estimated using the two-film resistance model based upon relative air-water concentrations. The average of air-sea exchange fluxes indicates a net deposition is occurring. These results suggest that the air–sea vapour exchange is an important process that intervenes in the mass balance of alkylphenols and the phthalates in the North Sea.
Organophosphorus flame retardants and plasticizers (OPEs) have been utilized for decades as plasticizers and, to a lesser extent, as flame retardants in various consumer products to improve their material properties. The research presented in this thesis investigated the occurrence, distribution and transport of OPEs with a focus on the coastal and estuarine environment. Due to the wide range of physicochemical properties of OPEs, the environmental fate and behaviour of OPEs was investigated over a range of compartments, starting from the atmospheric occurrence to the aquatic phase and the behaviour in sediments. The aim was to gather information on the OPE contamination situation in the coastal and estuarine environments, to identify specific contamination patterns for source assessment and to investigate the distribution behaviour of OPEs between gas- and particle-phases to evaluate their environmental transport mechanism. To achieve these scientific goals, sensitive and robust chemical analytical methods for the detection and quantification of OPEs in a variety of environmental samples using gas-chromatography coupled with tandem mass spectrometry were developed. Water samples were removed along the Elbe and Rhine Rivers to test the hypothesis of whether specific point sources, such as wastewater treatment plants, are the major input pathways for OPE contamination in rivers. A total of 65 water samples, including an intensive measurement campaign during the flood event in 2013 at the Elbe, was taken and analysed for OPEs. No obvious point sources were identified along either of the rivers analysed. No significant increase or decrease in the OPE concentrations or a change in patterns were observed over a transect of over 300 km at the Elbe, with an increase in water discharge of 2.5. This finding suggested that the OPE input in large rivers is primarily driven by diffuse sources, such as surface runoff, or by minor point sources rather than local point sources. To examine the specific pattern of OPE contamination in individual rivers and estuaries, 37 sediment samples from 8 rivers in Europe and China were analysed. With this analytical data, a fingerprint analysis of the OPE patterns identified could be conducted. All the rivers investigated in Europe displayed a very similar fingerprint. In contrast, the fingerprint from China differed significantly from the one in Europe. For example, in China, the OPE restricted in Europe, Tris(2-chloroethly)phosphate, was found to be one of the major OPE components, while Tris(2-butoxyethyl) phosphate, a major compound in Europe, was negligible in China. The investigation showed that the fingerprinting analysis is a useful tool to identify different regions or characterize specific rivers regarding their OPE contamination. In addition, it could be shown that legislative restriction and processes have an impact on local or even EU-wide contamination patterns. At a coastal site next to the German city of Büsum, 58 air samples were taken over one year. Using the newly developed analytical method, it was possible to analyse the gas, as well as the particle phase, of the samples collected with very low detection limits for OPEs. In contrast to expectations, no annual trend in OPE concentrations, phase distributions or patterns was observed, but the investigation of the phase distribution challenged the previous scientific consensus that OPEs occur as primarily bound to particles in the atmosphere. Several compounds were detected in significant amounts in the gas phase. To validate these novel results, a model analysis based on the chemical properties of OPEs was conducted using three different phase distribution models. The results from the environmental data were strongly supported by the simulations, and the formal knowledge could be refuted. Consequently, the atmospheric transport assumptions and estimations about the long-range transport of OPEs have to be reassessed because compounds in the gas phase undergo other types of transport degradation and elimination mechanisms than particle-boundones. The novel findings presented in this thesis challenged an important aspect regarding the perceived scientific knowledge about the behaviour of OPEs in the environment and call on the scientific community to reassess the environmental behaviour of OPEs. The insights presented on the patterns highlight the impact of environmental policies and regulatory mechanisms to work towards the final goal of a good environmental status and the avoidance of adverse effects of discarded chemicals on humans and the environment.
In sub-Saharan Africa, women own or partly own one third of all businesses, thereby having a large potential to contribute to the economic development and societal well-being in this region. However, women-owned businesses tend to lag behind men-owned businesses in that they make lower profits, grow more slowly, and create fewer jobs. To identify reasons for this gap and effective means to promote women entrepreneurs, large parts of the entrepreneurship literature have compared male and female entrepreneurs with regard to individual characteristics, paying only limited attention to the underlying environmental conditions. This is problematic as women entrepreneurs operate under different conditions than men, with particularly pronounced differences in sub-Saharan Africa. Against this backdrop, the goal of this dissertation is to contribute to a more profound understanding of women entrepreneurship in sub-Saharan Africa and its promotion through training by examining critical context factors. Specifically, the author analyzes two context factors that influence women's entrepreneurial performance and the success of training interventions: 1) women entrepreneurs' husbands and 2) the entrepreneurship trainer. These analyses are embedded in considerations of the cultural, social, and economic conditions women entrepreneurs in sub-Saharan Africa are facing. In Chapter 2, the author conducts a systematic literature review on spousal influence in entrepreneurship and identifies six recurrent types of influence. Complementing the literature originating from Western settings, she develops propositions on how the sub-Saharan context affects husbands' influence on women entrepreneurship in this region. In Chapter 3, she builds on a cultural theory and an economic theory of the household to develop and empirically test a theoretical model of husbands' constraining and supportive influences on women entrepreneurship in sub-Saharan Africa. The empirical results point to three distinct types of husbands that differ significantly in their impact on women entrepreneurs' business success. In Chapter 4, the author explores the influence of the trainer on the effectiveness of entrepreneurship training in sub-Saharan Africa by drawing on an unsuccessful training implementation. Qualitative analyses indicate that the use of adequate teaching methods is critical towards training success.
Consisting of three articles and a framework manuscript, this cumulative dissertation deals with sustainable compensation of chief executive officer (CEO) with a focus on climate-related aspects. Against the backdrop of the European action for sustainability and the EU Green Deal, the dissertation pays special attention to the consideration of climate-related aspects of corporate performance in CEO compensation. In this context, sustainable compensation is characterized by the consideration of long-term interests and sustainability of the company as well as by the inclusion of financial and non-financial aspects of environmental, social and governance performance (ESG) in compensation agreements. While this novel instrument of corporate governance aims to incentivize the implementation of sustainability-oriented corporate strategy, it is particularly important to unfold this incentive effect at the individual CEO level in view of their managerial discretion. The framework manuscript discusses the research objectives, the regulatory and theoretical background, the results of the dissertation and their implications in the context of regulation, research, and business practice. The essence of the dissertation are the three articles. The first article examines the current state of empirical research based on 37 articles that were published between 1992 and 2018. Based on a multidimensional research framework, the structured literature review compiles past research findings, identifies contentual and methodological foci in the research area, and derives questions for future research. The second article addresses the topic from a conceptual perspective. Taking the existing work as a starting point, a conceptual framework is derived, which organizes the determinants of carbon-related CEO compensation at societal, organizational, group and individual levels of analysis. On this basis, eight propositions are presented that seek to distinguish between the determinants which support and challenge the implementation of carbon-related CEO compensation. The third article focuses on the use of CO2-oriented performance indicators in CEO compensation. The empirical-qualitative study analyzes corporate disclosure of the 65 largest companies in the EU for the years 2018 and 2019. The study addresses the use of CO2-oriented performance indicators in corporate strategy and CEO compensation. It also examines which compensation components are determined with the help of CO2-oriented performance indicators, which type of performance indicators are used, and whether CO2-intensive and less CO2-intensive companies differ in this regard.
In spite of growing interest in companies’ contribution to sustainable development, the implementation of corporate sustainability, i.e. the integration of environmental, social, and economic issues, is not well understood. This cumulative PhD thesis aims to answer the research question whether sustainability management is only a transitory management fashion, or whether an effective implementation is actually taking place. The thesis consists of five papers, which are either published in refereed academic journals, accepted to be published, or planned to be resubmitted. The papers analyze three important elements of the implementation of corporate sustainability: motivation (why?), organizational units (who?) and management tools (how?). Combining these three elements supplies a framework for discussing the implementation of corporate sustainability management. The results, which are mostly based on surveys of large German companies, reveal that companies predominantly manage corporate sustainability because they seek legitimacy, rather than a competitive advantage, and because they follow acknowledged standards, guidelines, or ratings (institutional isomorphism) – possibly out of uncertainty on how to best handle a concept so complex and novel. Public relations is the organizational unit engaging in sustainability management most strongly, whereas accounting, finance, and management control engage the least. Hence, corporate sustainability is currently not implemented as a crossfunctional approach. Yet, there is indication of a growing strategic relevance of corporate sustainability. This is also reflected in the awareness and application of sustainability management tools, which have been increasing continuously between 2002 and 2010 – especially in terms of integrative tools serving to balance environmental, social, and economic issues. Furthermore, market incentives are gaining in importance over time. The thesis relates these results to management fashion theory. Although there is some indication that sustainability management might in fact be a transitory fashion, an analysis over time reveals an ongoing development of the elements analyzed. Thereby, the thesis demonstrates that corporate sustainability management can be considered more than a management fashion. One implication of the analysis is that both companies and researchers are called upon to foster the implementation of corporate sustainability, with positive incentives, e.g. by markets and consumers, turning out to be promising starting points. As opposed to pressure and expectations by stakeholders, focusing on opportunities might be more suitable to induce actual change of processes, products, services, or even business models in companies. In conclusion, the author hopes to make a significant contribution to the discussion on the implementation of corporate sustainability and to stimulate the development of new theoretical approaches.
This dissertation focused on the nature and role of organizational practices for the employment of older people and the extension of their working lives. The set of four articles is driven by the objective to further deepen our understanding of how organizations can facilitate ageing at work to the benefit of both, employees and employers. Findings are empirically based on qualitative expert interview data from Germany and the U.S. and several quantitative field studies among older employees in Germany. To bridge gaps in measurement of organizational practices related to aging at work, this dissertation proposes a new comprehensive, multifaceted, and thoroughly conceptualized measure of organizational practices related to aging at work, the Later Life Workplace Index (LLWI). Through the course of the four articles the LLWI is conceptually developed based on qualitative interview data, operationalized, validated based on multiple field studies among older workers, and applied in a multi-level study among older employees of 101 organizations. Results suggest that organizational practices are not uniform, but multifaceted in their presence within organizations and their effects for the employment of older workers. The LLWI distinguishes nine domains of practices including an age-friendly organizational climate, work design, individual development, and practices tailoring the retirement transition. Thus, it may lay the foundation for more granular organizational level research in the field. Further, this dissertation's fourth article applies the LLWI and argues based on person-environment fit and socio-emotional selectivity theory that organizational practices address different individual needs and, thus, affect employment depending on employees' individual characteristics. Results suggest that older employees' retirement intentions are effected by individual development, transition-to-retirement, and continued employment practices depending on their health resources. Application of the new measure in practice to improve organizations' response to the aging workforce and opportunities for future research based on the LLWI are discussed.
The literature on term bids by presidents tends to focus on the institutional arrangements to hinder such term bids in the first place, on presidential strategies to circumvent the constitutional law, or on counteractions of political elites. Mobilizations against such attempts by presidents to run for office again, after reaching the end of their last allowed term, are often solely included as "pressures from below". To address these shortcomings, this dissertation explores the issue of term amendment struggles through the lenses of contentious politics systematically combined with insights of revolution theories and democratization studies. Its conceptual perspective therefore lies on the interactions of actors and their constellations to each other as well as to institutions. The author deduces three diverse pathways to promote institutional change and prevent democratic backslidings – through political elites, (political) allies, and security forces. By selecting two cases that are most similar in terms of institutions and youth movements at the forefront, Senegal (2011-12) and Burkina Faso (2013-14), this analysis offers insight in the divergence of the struggles and their outcome. Because in both cases, the announcement of the presidents to run for another term in office led to broad mobilization led by youth movements against such tenure amendments, the political system in general and socioeconomic inequalities - but with diverging results. In Burkina Faso, Blaise Compaoré eventually resigned while Abdoulaye Wade in Senegal candidated again, legitimized by the Constitutional Court. Based on extensive fieldwork, including interviews with movement leaders and their allies, as well as a comprehensive media analysis and the SCAD databank for the analysis of protest events, the author differentiates and reconstructs the various phases of the conflict. The results of the dissertation point at two dimensions most relevant to comprehend the dissimilar pathways the struggles took – the reach of mobilization and, closely interlinked to the first, the refusal of soldiers to obey orders. It shows further that these differences go back to the respective history of each country, its former protest waves, and political culture. Although both presidents faced mass mobilization against their unconstitutional candidature, only in Burkina Faso it eventually led to an ungovernable situation. The dissertation concludes by reflecting on lessons learned for future democratic backslidings by presidents to come and avenues for future research – and thus offers fruitful insights.
Whereas the extant literature discusses what Sustainability-Oriented Innovations (SOIs) are and why firms develop them, little is known about how they are developed. To enable firms to innovate for sustainability, it is essential to know more about the processes underlying SOI development, which are considered as very difficult, with many firms failing. Drawing on several academic papers and relying on qualitative research methods, the thesis uses the Fireworks model to examine how innovation processes unfold at established small and medium-sized enterprises (SMEs). The main contribution of the thesis is to advance the Fireworks model to the context of SOIs unfolding at SMEs. The findings reveal that SOIs unfold in an emergent, somewhat chaotic way, that duration and outcome are uncertain, that the overall journey is composed of multiple intertwined innovation paths, of which several will likely lead to setbacks. To manage this complex process, the thesis suggests to set four management foci: (1) to create a dedicated organizational unit for exploration, (2) to create conditions allowing intelligent learning for efficient exploration, (3) to carry out in-depth investigation of the related technological innovation systems, and (4) to plan carefully the re-integration of the innovation into the core business for commercialization.
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.
The question whether representation of travel experience actually leads to personal prestige enhancement has been widely neglected so far. The study of prestige benefits of travel is a necessary endeavour to develop suitable methodological approaches toward the concept, in order to close critical knowledge gaps and enhance scientific understanding. The present thesis lays out the rationale and results of three research projects which shed light onto the relationship between touristic self-presentation and its effects on personal prestige evaluations of the social environment. The empirical studies conclude in the following main findings: (1) Leisure travel is a useful means for people to self-express in a positive way, and material representations of travel are frequently displayed to others. Tourists make use of travel experience to self-present in a positive way by uploading photos on social media, collecting and displaying souvenirs, wearing jewellery and clothing from their last trip, or talking about their trips to others. They express positive self-messages about personal character traits, affiliation to social in-groups and proof of having travelled somewhere. The findings ascertain the utility of travel representations for positive self-expression, showing that travel experience is an effective vehicle for conspicuous consumption and self-expression as an antecedent for personal prestige enhancement. (2) Personal prestige is an element of social relations, and holds capacity to affect perceptions of social inclusion and social distinction, so it has to be conceptualised as a multidimensional construct. In a tourism context, personal prestige is reliably measurable along the four dimensions of hedonism, social inclusion, social distinction and prosperity. The herein developed Personal Prestige Inventory (PPI) is a valid, reliable and parsimonious measurement tool which substantially enhances methodological approaches toward empirical research into personal prestige. (3) The way in which people represent travel experience to others measurably affects how their personal prestige is evaluated by social others. Empirical evidence of a series of experimental studies provides support for the assumption that representation of travel experience has an effect on the social evaluation of tourists' personal prestige. Experimental variance suggests small to moderate effects on personal prestige depending on the amount of leisure information given about a person, participation in tourism, and the destination and type of travel represented. This evidence is reasonable basis to conclude that whether and how people travel, and whether and how they share travel experience with others, does measurably affect social other's evaluation of their personal prestige.
Companies are invited to contribute to the United Nations' 17 Sustainable Development Goals (SDGs) and sustainability management accounting (SMA) has an important role to play in achieving them. However, if companies are to address the SDGs and linkages beyond organizational boundaries, SMA needs a broader scope than is conventionally assumed. Therefore, the author advances a multi-level framework that addresses context, action-formation, and transformative contributions (CAT) in the following directions: first, an innovative systematic method that allows screening company-related SDGs and assessing corporate contributions to selected SDGs is introduced; second, management control systems are integrated to support managers in guiding employee behavior to make contributions to the SDGs; and, third, self-reinforcing mechanisms of the path-dependence theory are incorporated to serve as a guide to identifying barriers to individuals and groups becoming involved in SMA. This advanced CAT framework contributes to corporate practice and research by providing a multilevel framework that offers concrete management guidance for SMA to address the SDGs. It also facilitates analysis of both enabling and inhibiting factors at the organizational level. The advanced CAT framework has several implications for SMA: it promotes backcasting from the SDGs for benchmarking purposes, integrates different social, environmental, and economic issues, facilitates future-oriented action and transformation planning, addresses different layers such as the company as well as individuals and groups within it and enables to identify barriers hindering individuals and groups from becoming involved in SMA.
This paper-based dissertation deals with capital structures and tax policies of German family businesses. Family firms as the predominant company form in Germany are mainly characterized by the overlapping of the two spheres family and business, both having different goal systems and preferences. This also has an impact on decision making with regard to corporate finance including the application of tax avoidance policies. In Germany, bank finance is the dominant financing source for family firms but there is a preference for internal finance since it comes along with more external independency. Extant research usually bases its results on samples of publicly listed companies. These studies come up with different results regarding family firms' actual financing preferences and capture their heterogeneity only to a very little extent. In this light, the present dissertation and its three papers examine different research questions in the context of capital structure decisions and tax avoidance in family firms. All the three papers apply a quantitative empirical research design. The first paper is a comparison between capital structures of family firms and non-family firms. The paper examines differences in bank debt and trade credit ratios. 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 second paper is an in-depth examination of drivers of bank debt levels within the group of family firms. Further, it addresses heterogeneity amongst family firms and combines survey results and corresponding financial information. This represents a first attempt to capture family firm heterogeneity and its link to financial issues. The study shows that the more power in the company is exerted via management or supervisory board by the family, the less bank debt is used. Paper three is an extension of the previous two studies as it sheds light on tax avoidance, a significant instrument to strengthen the internal financing capability of a firm. This also takes up a research gap as there is very little research on taxation in family firms. Contrary to the expectation, the study reveals that private family firms might pay less tax than their non-family peers.
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.
Metals fulfill crucial functions in areas as diverse as renewable energy, digitization and life style appliances, mobility, communication, or medicine. In the context of sustainability, achieving a more sustainable metal use means (i) minimizing the adverse effects associated with metal production and use and (ii) sustaining the availability of metals in a way that benefits present and future generations. Urgent need to act to avoid bottlenecks as well as meeting the challenge of possible conflicts of use among those areas of application calls for appropriate strategy making to intervene in the complex field of metal production and use that involves various, often interlinked operating levels, actors, and spatial and temporal scales. This dissertation focuses on strategies as a means to intervene in a system. It pursues the question, which design features could guide future strategy making to foster sustainability along the whole metal life cycle, and especially, how a better understanding of temporalities, i.e. understanding time in a diverse sense, could improve strategy design and help to bridge the assumed "transformation-material gap". This research converges the results from four research studies. A conceptual part explores the role of temporalities for interventions in complex and interlinked systems, which adds to the conceptual basis, on which the empirical part builds up to explore present and future interventions in metal production and use. The research revealed three essential needs that future strategies must tackle: (i) managing the complex interlinkages of processes and activities on various operational levels and spatial and temporal scales, (ii) providing clear guidance concerning the operationalization of sustainability principles, and (iii) keeping activities within the planet’s carrying capacity and embracing constant change as an inherent system characteristic. In response to these needs, the author developed three guidelines with two design features each (one relating to content, and one to the process of formulating and implementing the strategy) to guide future strategy making. The results show that time matters in this respect. If considered in close relation to space and diversely understood in the sense of temporalities, it serves to (i) understand the impact (duration and magnitude) of an intervention, (ii) recognize patterns of change that go beyond establishing linear, one-dimensional connections, and (iii) design interventions in a way that considers the resilience of a system. These findings can contribute to closer considering our understanding of transformation processes towards sustainability in future interventions in metal production and use.
European species-rich grasslands are threatened both by land use intensification as well as land abandonment. The studies shown in this thesis tested the possible use of ecological knowledge to ensure hay productivity whilst maintaining diversity of grasslands, with a view to informing ecological restoration. The overall approach was to understand interactions between plants, to study diversity effects on productivity, and mainly investigate how plant functional groups that arrive first in the system can create priority effects that influence community productivity both above- and belowground. A grassland field experiment was established and monitored for four years, in order to verify the effects of manipulating the order of arrival of different plant functional groups, as well as the sown diversity level on productivity and methane yield. The overall findings were: a) sowing legumes first created priority effects aboveground (higher biomass) and belowground (lower root length), plants invested less in roots and more in shoots, b) priority effects were more consistent below than aboveground, c) sown diversity did not affect aboveground biomass, d) the order of arrival treatments indirectly affected methane yield by affecting the relative dominance of plant functional groups. Since the researchers lack information on how legumes and non-legumes interact spatially belowground, (particularly related to root foraging) a controlled experiment was performed, using two grass species and one legume. The identity and location of the neighbours played a role in interactions, and the order plants arrived modulated it. When the focal species (grass) was growing with a legume it generally equated to the same outcome as not having a neighbour. Roots from the focal species grew more toward the legume than the grass neighbour, indicating a spatial component of facilitation. Since these studies involved root measurements, a method study was also conducted to verify how comparable and accurate are root length estimates obtained from different techniques. Results showed that the use of different methods can lead to different results, the studied methods did not have the same accuracy, and the automated methods can underestimate the root length. Overall, the results allow to conclude that different groups of plants arriving before others affected above and belowground biomass, roots may be key drivers during the creation of these priority effects, and interaction outcomes between plants depended on neighbour identity and location, modulated by the order they arrive in. The results suggest that priority effects can be used by sowing different species or plant functional groups at different time to steer a community to a desired trajectory depending on the restoration goal. However, there is a need to test contingency, potential, and long term impacts of such possible tools for restoration.
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.
Transforming the International Food Supply – Sustainable Practices in Small Intermediary Businesses
(2021)
The global food system faces many complex challenges, and there is general agreement that a transformation is needed. While localizing food has been proposed as a means to this end, changing global food supply chains may also lead to sustainable food systems. Because most food systems today have an international dimension and are likely to remain connected, on one way or another, to other ones across the globe, it is necessary to find solutions to problems such as exploitation or environmental degradation. Addressing this challenge and the related gap in the literature, this study examines the emerging practices of small intermediary food businesses, which act between agricultural producers and consumers, and may have the potential to advance sustainability in international food supply. Including a systematic review of the literature on food systems change (Study#1), this dissertation adopts a transformational sustainability research methodology, which is solution-oriented, aims to integrate system, target and transformation knowledge, and is characterized by a transdisciplinary research practice. It conceptualizes challenges of international food supply and empirically investigates entrepreneurial solution approaches to address these challenges (Study#2). Two transdisciplinary research projects with small coffee businesses located in Germany, Mexico, and the U.S. were conducted to examine how these approaches could be implemented (Study#3, Study#4, Workshop reports 1+2). Overall, this study shows that challenges in international food supply chains can be conceptualized as negative effects of large geographical and relational distances. It also identifies five entrepreneurial solution approaches specified by twelve sustainability-oriented design principles to address these negative effects. Creating relational proximity between supply chain actors, that is, strong relationships based on knowledge and care, seems to be a key factor to advance sustainability in international food supply.The results also suggest that by building such strong relationships and changing the fundamental principles of international food trade, small intermediary businesses could be important agents in food system transformations.
The present doctoral dissertations seeks to shed theoretical and empirical light on how complexity and different approaches to manage it affect perceptions, behaviors, and outcomes in integrative negotiations. Chapter 1 summarizes the following chapters, describes their individual contribution to the present thesis, and outlines avenues for future research. In Chapter 2, a theoretical model comprising of task- and context-based determinants of complexity in negotiations is developed. In Chapter 3, the effects of the number of issues (high vs. low) as one essential determinant of complexity on parties' trade-off behavior and joint outcomes are investigated in a series of four experiments. Furthermore, negotiators' cognitive categorizing of issues (i.e., their mental-accounting approach) is examined as the underlying psychological mechanism. Results reveal that more issues lead to a higher risk of scattering the integrative potential between cognitive categories (i.e., mental accounts), reducing trade-off quality and joint outcomes. In Chapter 4, the generalizability of the detrimental effect of the number of issues on joint outcomes is tested across varying numbers of issues in a meta-analysis. Moreover, boundary conditions for the effect are investigated. Results confirm the generalizability of the number-of-issues effect, but no relevant boundary conditions are identified. In Chapter 5, the effects of different mental-accounting approaches on negotiators' judgment accuracy, trade-off behaviors, and negotiation outcomes are examined in a series of five experiments. Results demonstrate that categorizing a moderate number of issues into each mental account leads to a higher judgment accuracy, trade-off quality, and joint outcomes, but only if negotiators manage to pool the integrative potential within these accounts. Finally, Chapter 6 takes a broader perspective on different integrative strategies in negotiations (i.e., expanding the pie, logrolling, solving underlying interests), thereby laying the groundwork for future research.
Stretching is primarily used to improve flexibility, decrease stiffness of the muscle- tendon unit or reduce risk of injury. This cumulative dissertation includes six studies aiming to investigate the effects of long-lasting static stretching training on maximum strength capacity, hypertrophy and flexibility in the skeletal muscle. Before starting own experimental studies, a meta-analysis of available animal research was conducted to analyze the potential of long-lasting stretching interventions on muscle mass and maximum strength. To induce long-lasting stretching on the plantar flexors and to improve standardization of the stretch training by quantifying the angle in the ankle joint while stretching, a calf muscle stretching orthosis was developed. In the following experimental studies, the orthosis was used to induce daily long- lasting static stretching stimuli with different stretching durations and intensities in the plantar flexors to assess different morphological and functional parameters. For this, a total of 311 participants were included in the studies and, dependent on the investigation, the effects of daily stretching for 10-120 minutes for six weeks were analyzed. Therefore, effects on maximal isometric and dynamic strength as well as flexibility of the plantar flexors were investigated with extended and flexed knee joint. The investigation of morphological parameters of the calf muscle was performed by determining the muscle thickness and the pennation angle by using sonographic imaging and the muscle cross-sectional area by using a 3 Tesla magnetic resonance imaging measurement. In animals, the included systematic review with meta-analysis revealed increases in muscle mass with large effect size, muscle cross-sectional area, fiber cross-sectional area, fiber length and fiber number. The thereafter performed experimental studies from the laboratory showed a range of trivial to large increases in maximum strength and ROM dependent on stretching time, training level and testing procedure. Furthermore, significant moderate to large magnitude hypertrophy effects in muscle thickness and trivial to small increases in muscle crosssectional area were demonstrated. The results are discussed based on physiological parameters from animal studies and in the front of knowledge in resistance training, suggesting mechanical tension to be one important factor to induce muscle hypertrophy and maximal strength increases. Further explanatory approaches such as hypoxia and changes in the muscle tendon unit are debated in the following. Since these studies are the first investigations on long-lasting stretch-mediated hypertrophy in humans, further research is needed to explore the underlying mechanisms and confirm the results in different populations to enhance the practical applicability for example in clinical populations when, e.g. counteracting muscular imbalances or sarcopenia in the elderly.
Die vorliegende Dissertation wendet ein theoretisches Modell zum Zusammenhang zwischen Wirtschafts- und Umweltleistung auf existierende und eigene empirische Untersuchungen an. Die auf Basis des Modells formulierten Hypothesen werden mit eigenen empirischen Daten aus Europa insbesondere mit Bezug auf betriebliche Umweltstrategien und auf input-orientierten bzw. output-orientierten Umweltschutz untersucht. Dies ermöglicht insbesondere eine Bewertung des Einflusses der Strategiewahl. Die empirische Untersuchung basiert auf zwei unterschiedlichen Datensätzen. Es werden zunächst empirische Daten zur Umweltleistung von Papierfirmen in verschiedenen Ländern (Niederlande, England, Deutschland und Italien) untersucht, und dabei bei einer output-orientierten Messung der Umweltleistung ein im wesentlichen negativer Zusammenhang zwischen Umwelt- und Wirtschaftsleistung ermittelt. Bei Verwendung eines input-orientierten Maßes für die Umweltleistung wird ein im wesentlichen insignifikanter Zusammenhang gefunden. In der zweiten empirischen Untersuchung wird im Rahmen einer Befragung von Unternehmen des verarbeitenden Gewerbes in England und Deutschland eine Unterscheidung von betrieblichen Umweltstrategien vorgenommen. Dabei erfolgt auf Basis der Kriterien des Environmental Shareholder Value eine Einteilung der Firmen in solche mit wertorientierten Umweltstrategien und solche ohne spezifische Wertorientierung. Auf Basis dieser Unterscheidung wird die aus der zentralen Fragestellung der Dissertation abgeleitete Hypothese untersucht, dass der Zusammenhang zwischen Umweltleistung und Wirtschaftsleistung für Unternehmen mit einer wertorientierten Umweltstrategie positiver ist als für solche ohne spezifische Wertorientierung des Umweltmanagements. Diese Hypothese wird dahingehend bestätigt, dass für Firmen mit wertorientierter Umweltstrategie ein weitgehend positiver Zusammenhang zwischen Umweltleistung und umweltbezogenen Dimensionen der Wettbewerbsfähigkeit nachgewiesen wird.
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 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.
This dissertation investigates work ability as a concept that supports workers, employers, and societies in the extension of working lives, and how work ability is related to the level of self-determination in the transition to retirement, and ultimately life satisfaction. In the first study of this dissertation, the Work Ability Survey-R (WAS-R) was translated from English into German and then evaluated regarding its psychometric properties and construct validity. The WAS-R operationalizes work ability as the interplay of personal and organizational resources and thus allows companies to derive targeted interventions to maintain work ability. In the second study, the WAS-R was examined together with the questionnaire Work-Related Behavior and Experience Pattern (Arbeitsbezogenes Verhaltens- und Erlebensmuster, AVEM) regarding its construct validity. A striking feature of this study was the high number of participants with the answering pattern indicating low work-related ambitions and protection. Persons with this pattern are in danger of entering the risk pattern for burnout in the future. The findings support the validity of the WAS-R. In the third contribution, two studies examined the experience of control (i.e., autonomy) in the transition to retirement as a mediator between previous work ability, health, and financial well-being, and later life satisfaction in retirement. Control was found to partially mediate the relationship between work ability and later life satisfaction. Different mechanisms on later life satisfaction of work ability and health, and the subjective and objective financial situation were found. This dissertation contributes to research on and practice with aging workers in two ways: (1) The German translation of the WAS-R is presented as a useful instrument for measuring work ability, assessing individual and organizational aspects and therefore enabling employers to make targeted interventions to maintain and improve work ability, and eventually enable control during later work life, the retirement transition and even old age. (2) This dissertation corroborates the importance of good work ability and health, even in old age, as well as control in these phases of life. Work ability is indirectly related to life satisfaction in the long period of retirement, mediated by a sense of control in the transition to retirement. This emphasizes the importance of the need for control as postulated by the SDT also in the transition to retirement.
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.
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 worldwide decline of plant and insect species during the last decades has far-reaching consequences for the functionality of ecosystems and their inherent processes. Pollination as one of them is an indispensable ecosystem service for human wellbeing. However, an increasing number of pollinator and plant species are threatened by multiple, interacting, and sometimes synergistic causes that are becoming a growing threat to ecosystem functioning. Given the loss of plant species diversity, it is increasingly difficult for pollinators to find food throughout the year. Therefore, this study analyses the influence of plant diversity on pollinators. The study was conducted in the course of the Jena Experiment, which is a long-term biodiversity experiment (since 2002) with 60 plant species, common to Central European Arrhenatherum grasslands. With a plant diversity gradient of 1, 2, 4, 8, 16, and 60 plant species per plot, time-series data resulted from a wide range of ecosystem processes, ranging from productivity, decomposition, C-storage, and N-storage to herbivory, and pollination. These were studied to investigate the mechanisms underlying the relationships between biodiversity and ecosystem processes. Chapter 2 studies the spatio-temporal distribution of pollinators on flowers along an experimental plant diversity gradient. In particular, the spatial pollinator behaviour was examined. Chapters 3 and 4 continues on the chemical composition of flower nectar (nectar) of various plant species. The chemical composition of the nectar was analysed for the two most important macronutrients, carbohydrates (C) and amino acids (AA), using high performance liquid chromatography (HPLC). Subsequently, their contents were analysed in terms of concentration, proportional content and the ratio of carbohydrates to amino acids (C:AA). In Chapter 3, the nectar of 34 plant species from the grasslands of the Jena Experiment was compared. In Chapter 4, nectar was investigated in the context of diversity effects on the example of the plant species Field Scabious, Knautia arvensis. It was analysed to what extent the nectar quality (nutrient content) differs between plant individuals of one species. Overall, these studies indicate how fragile plant-pollinator interactions are but also how important plant species-rich grasslands are to support plant-pollinator interactions. Increased plant species diversity is essential to ensure the availability of flowering resources throughout the year. Pollinators, such as honeybees, bumblebees, solitary bees, and hoverflies can use the niches in time and in vertical space complementarily. However, in plant species-poor grasslands there may be more niche overlaps, which is probably due to a reduced availability of resources. This points to the need to include different plant species belonging to different plant families, whose nectar may have evolved in response to morphological flower traits and metabolic pathways. Therefore plant species diversity can supply pollinators with nectar differing in carbohydrate and amino acid content and thus differing in quality. Also C-AA ratios have proven to be a useful measurement to reveal differences between plant species. In addition, C:AA ratios were not differing in nectar of K. arvensis individuals growing in different plant species richness levels, although their nectar seemed to be more attractive in mixtures with 16 plant species, likely due to higher content of essential and phagostimulatory amino acids than in plant species-poor mixtures.
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.
Excessive fertilizer use leads to nutrient imbalances and losses of these to the environment through leaching, runoff and gaseous emissions. Nutrient use efficiency (NUE) in agriculture is often low and improving it could increase the sustainability of agricultural systems. The main aims of this thesis were to gain a better understanding of plant-soil-microbe interactions in order to improve agricultural NUEs. The studies included experimentally tested how crops respond to addition of high carbon amendments, fertilizer application rates and timing, and crop rotations. Furthermore, methods for measurement of roots were compared and a protocol for measurement of roots was developed. The first experiment simulated an agricultural field using mesocosms. In this setting, the researchers tested the effect of 4 previous crops (precrops), which either had or did not have a symbiosis with arbuscular mycorrhizal fungi (AMF)/rhizobia, on the focal crop (winter barley). They also tested the addition of high carbon amendments (wheat straw/sawdust) for immobilization of residual soil nitrogen (N) at harvest of the previous crop. Overall, the findings were that non-AMF precrops had a positive effect on winter barley yield compared to AMF precrops. Wheat straw reduced N leaching, whereas sawdust addition had a negative effect on the yield of winter barley. The second experiment tested the effect of different fertilizer (N/phosphorus (P)) application timings on plant traits grown in rhizoboxes. Overall, delaying N application had a more detrimental effect on plant biomass than delaying P application. The root system increased its root length initially due to N-deficiency, but was quickly thus N-limited that root length was relatively lower than the control group. Because of the many root related measurements in the second experiment, a step-by-step method for measuring root traits under controlled and field conditions was developed and included in this thesis. This method paper describes precisely how root traits of interest can be measured, and helps with deciding which approach should be taken depending on the experimental design. Additionally, the authors compared the bias and accuracy of several popular root measurement methods. Overall, these results highlight the importance of crop choice in crop rotations and the plasticity of root systems in relation to nutrient application. The results show high carbon amendments could reduce nitrate leaching after the harvest of crops, especially those with high risk of nitrate leaching, although they had only small impacts on yield.
This thesis deals with sustainability in African Higher Education Institutions (HEIs) and the influence of language in achieving sustainable development. Several authors highlight the existing imbalance of sustainability research in higher education, with most publications focusing on the so-called Global North. Little is known about sustainability in the so-called Global South, and in African educational institutions in particular. The first article of this thesis investigated existing sustainability activities in African HEIs. Rather than focusing on the shortcomings, the paper took a positive stance, opposing the predominant language of deficits in research on Africa. In the Delphi study conducted, 32 experts from 29 HEIs in 16 African countries described the sustainability activities they are engaging in. Experts provided information about their experiences in their respective HEI, while language and culture emerged as areas in need of further research. The second article therefore focused on the relationship between language and education for sustainable development in African educational institutions, and systematically reviewed scholarly literature regarding this connection. Authors of the reviewed 33 papers approached this connection mainly on a theoretical and philosophical level, focusing on education and Africa as a whole rather than specified forms of education in specific countries. The third article examined the views of Tanzanian higher education students and graduates regarding language and sustainability. Participants explained how they integrate sustainability and the Sustainable Development Goals (SDGs) into their research and how they approach translations in the process. In the ensuing interviews, participants estimated that only a fraction of people outside of academia are aware of sustainability and the SDGs, rendering the achievement of target 4.7 unlikely. This thesis therefore contributes to a better understanding of the current challenges in implementing sustainability and the SDGs in African educational institutions. It highlights the need to integrate (local) African languages in order for sustainability activities as well as the SDGs to be successful.
This thesis deals with the influence of sustainability communication on the purchase decision of sustainable tourism products involving German specialist tour operators. Sustainability communication is a challenge, because sustainable tourism is an abstract and vague concept which consumers find it difficult to grasp and about which they are sceptical. The service characteristics of tourism products complicate the decision making stage, which is a high-involvement situation of uncertainty to which sustainable product attributes add complexity. As an introduction, an interdisciplinary theory discussion reveals knowledge gaps in terms of the value-belief-norm theory and the elaboration likelihood model (ELM). The first article, which is the first systematic literature review on the topic, reveals that there is a limited theoretical understanding of sustainability communication, a lack of practical understanding of how to design sustainability messages, and an inadequate set of methodologies for its research. It identifies knowledge gaps concerning: the holistic approach to sustainability communication; its role in the attitude-behaviour gap; an interdisciplinary theoretical understanding focusing on belief-based social psychological theories and theories of persuasion; qualitative methods; and experimental design. The second article investigates the role of sustainability communication in the attitude-behaviour gap, employing the value-belief-norm theory to explain how information is processed by special interest customers. Interview findings show that ineffective sustainability communication is the reason for the gap and that customers unintentionally booked sustainably. The study identifies eight groups of beliefs which explain the processing of sustainability attributes. Sustainability information is effective when it is value-congruent, that is, when customers perceive they can make a difference, they begin to ascribe a responsibility to themselves. The third article investigates how to design an effective sustainability message in tour operator advertising. Drawing on the ELM, the study shows that appeal type does not significantly influence persuasion but the topic presented is important. Cultural sustainability is the sustainability topic that is most persuasive for cultural tourists, while consumer prior knowledge and issue-involvement with the topic promote successful information processing.
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.
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.
Crowdfunding is considered a promising instrument for transforming existing socio-technical regimes by financing radical innovations of such entrepreneurs. However, this potential has not yet been fully explored. Therefore, this dissertation addresses the overarching research question of how sustainable entrepreneurs can exploit the full potential of investment-based crowdfunding to develop from niche operators to actors in the socio-technical regime. Five journal articles and one book chapter are included in this PhD project, which use a wide range of quantitative methodologies. In the framework paper, the findings are conceptually evaluated on a meta-level by applying the multi-level perspective. The key insights can be assigned to four categories, including the financing and marketing function, the target group, and the project presentation. The analysis shows that investment-based crowdfunding is suitable to equally fund and market the business ideas of environmental entrepreneurs, since the quest for entering the mass market is highest for such ventures. In contrast, purely social entrepreneurs tend to conduct crowdfunding projects on a smaller scale and probably aim to stay in the niche. Nevertheless, profit-oriented social entrepreneurs are still encouraged to use investment-based crowdfunding for funding and marketing purposes. The prominent display of environmental effects (e.g. the amount of compensated greenhouse gases) and financial incentives (e.g. high interest rates) has a high impact on the investment decision of individuals on investment-based crowdfunding platforms. The case of fairafric is used as a best practice example to demonstrate how crowdfunding can be a stepping stone for sustainability-oriented niche actors to enter the mass market. The fair-trade and organic chocolate manufacturer has undergone six crowdfunding campaigns which enabled it to grow and build a strong community of supporters. The outcomes of this dissertation clarify how sustainable entrepreneurs can unleash the potential of investment-based crowdfunding for financing and marketing purposes.
Algae-bacteria-based biotechnology has received more and more attention in recent years, especially in the subtropical and tropical regions, as an alternative method of conventional multistep wastewater treatment processes. Moreover, the algal biomass generated during wastewater treatment is regarded as a sustainable bioresource which could be used for producing biofuel, agricultural fertilizers or animal feeds. Although this technology is attractive, a number of obstacles need to be solved before large-scale applications. The main purposes of this work are to find more effective biomass harvesting strategies and develop high-effective algal-bacterial systems to improve wastewater treatment performance, biomass generation rate and biomass settleability. A wastewater-borne algal-bacterial culture, cultivated and trained through alternate mixing and non-mixing strategy, was used to treat pretreated municipal wastewater. After one month cultivation and training, the acclimatized algal-bacterial system showed high carbon and nutrient removal capacity and good settleability within 20 minutes of sedimentation. Algal biomass uptake was the main removal mechanism of nitrogen and phosphorus. The biomass productivity, nitrogen and phosphorus accumulation in biomass during the wastewater treatment process were investigated. The characterization of the microbial consortium composition in the enriched algal-bacterial system provided new insights in this research field. Aerobic activated sludge which already showed good settleability was used as bacterial inoculum to enhance the wastewater treatment performance and biomass settleability of algal-bacterial culture. The influence of different algae and sludge inoculum ratios on the treatment efficiency and biomass settleability was investigated. There was no significant effect of the inoculation ratios on the chemical oxygen demand (COD) removal. But algae/sludge inoculum ratio of 5 showed the best nitrogen and phosphorus removal efficiencies (91.0 ± 7.0% and 93.5 ± 2.5%, respectively) within 10 days. Furthermore, 16S rDNA gene analysis showed that the bacterial communities were varying with different algae and sludge inoculation ratios and some specific bacteria species were enriched during the operation. Four commonly used and high-potential microalgae species including one cyanobacteria (Phormidium sp.) and three green microalgae species (Chlamydomonas reinhardtii, Chlorella vulgaris and Scenedesmus rubescens) were cultivated and trained through alternate mixing and non-mixing strategy for tertiary municipal wastewater treatment. After one month of cultivation, the four microalgae species were compared in terms of biomass settleability, nutrient removal rates and biomass productivity. The three green microalgae showed good settleability within 1 h sedimentation and had higher biomass generation rates (above 6 g/m2/d). The nutrient removal efficiencies were 99% for the four selected microalgae species but within different retention time, resulting in 3.66 ± 0.17, 6.39 ± 0.20, 4.39 ± 0.06 and 4.31 ± 0.18 mg N/l/d (N removal rate) and 0.56 ± 0.07, 0.89 ± 0.05, 0.76 ± 0.09 and 0.60 ± 0.05 mg P/l/d (P removal rate) for Phormidium sp., Chlamydomonas reinhardtii, Chlorella vulgaris and Scenedesmus rubescens, respectively. A mixed algal culture composed of three selected high-effective green microalgae (Chlamydomonas reinhardtii, Chlorella vulgaris and Scenedesmus rubescens) was used for tertiary municipal wastewater treatment. The key biotic factor (algal inoculum concentration) and abiotic factors such as illumination cycle, mixing velocity and nutrient strength were studied. Based on the nitrogen and phosphorus balance, it was found that assimilation into algal biomass was the main removal mechanism.
Derivatives are contracts between two parties, a buyer and a seller. The contract will be fulfilled in some point in the future at a predetermined price. The value of those contracts is based on an underlying entity which can be a traded asset or even the weather. Derivatives contain chances, but also risks, investor should be aware off. This thesis aims to deeply analyze two derivative products in the German market and one risk for each which influences the prices of those products. The first part of this thesis focuses on warrants and the issuer's credit risk involved. It finds evidence that the issuer's credit risk influences the connection between warrant characteristic and its prices. Over time this connection is unstable partly driven by the issuer's credit risk. The second paper of this thesis shows that issuers seem to use their credit risk systematically to influence warrant prices. Evidence is found that the changes in credit risk are not fully included in the prices directly, but that the adjustment to the new level of credit risk takes several days. In addition, the issuer's adjustment to changes in credit risk are different for credit risk increases than for credit risk decreases. Especially after financial crisis, in more stable times, evidence is found for such adverse pricing pattern. The third part of the thesis focuses on energy derivatives traded at the Europe Energy Exchange and analyses the influence of weather parameters on energy derivatives with different load profiles and time horizons. This part of the thesis finds that especially wind speed and sun hours have a strong influence on energy derivatives. However, not all products are influenced in the same manner. Products with a longer time horizon are influenced less than the product with a short horizon. Moreover, products comprising hours of the day where energy consumption is expected to be higher are influenced stronger than products comprising hours of a day with lower time consumption. The thesis shows that derivatives are not alike and that it is needed for future research to differentiate between products and the risks which are involved. Since even though we classify them all as derivatives the risks influencing the derivative´s prices do vary tremendously.
Sustainability and Justice: Conceptual Foundations and Cases in Biodiversity and Fishery Policy
(2014)
Sustainability aims at justice in a threefold sense: intragenerational justice, intergenerational justice, and justice towards nature. However, the justification, specific content and practical implications of justice claims and obligations in the sustainability context often remain underspecified. This dissertation therefore asks: How can the concept of justice be structured systematically? How can justice be specified in the context of sustainability? Which specific problems of justice arise in sustainability policy? And what are the respective contributions of (sustainability) economics and (sustainability) ethics? The five papers of this cumulative dissertation approach these issues from different angles, working at the conceptual level and at the level of cases from biodiversity and fishery policy. In Paper 1, a formal conceptual structure of justice is developed, which lists the conceptual elements of justice conceptions: the community of justice including claim holders and claim addressees, their claims (and corresponding obligations), the judicandum (that which is to be judged as just or unjust), the informational base for the assessment, the principles of justice, and on a more practical level, the instruments of justice. By specifying these conceptual elements of justice, it is possible to analyse and compare different conceptions of justice. In Paper 2, the normative dimension of sustainability is discussed in terms of justice. Based on the identification of certain core characteristics of the concept of sustainability, we determine the specific challenges of justice in the context of sustainability along the conceptual structure of justice (from Paper 1). Inter alia, we show that sustainability calls for the integration of justice claims in the relationships with contemporaries, future humans and nature in a non-ideal context characterized by uncertainty, systemic mediation and limits. Paper 3 addresses the contribution of economics to the assessment of trade-offs between intergenerational and intragenerational justice. Economic analysis can delineate the opportunity set of politics with respect to the two justice objectives and identify the opportunity cost of attaining one justice to a higher degree. While the two justices are primary normative objectives, the criterion of efficiency - when directed at the attainment of these justice objectives - has the status of a secondary normative objective. Paper 4 constitutes a case study, reconstructing the ´biopiracy´ debate from a justice perspective. The paper links to the so called Access and Benefit-Sharing framework of the Convention on Biological Diversity, and addresses the question, which problems of justice arise regarding the utilization of genetic resources and traditional knowledge, especially if associated with patenting. It is shown that the predominant perspective of justice-in-exchange is insufficient and therefore complementary conceptions, namely of distributive justice, corrective justice and structural justice have to be taken into account. Paper 5 empirically assesses the justice notions of stakeholders in the Newfoundland fishery, building on qualitative semi-structured interviews and a combination of inductive and deductive coding. A central result is that inshore fishers are seen as the main claim holders, with a claim to participate and being listened to, and the opportunity to make a living from the fishery. Recognition, participation and distribution are all important domains of justice in the context of the Newfoundland fishery. The paper also discusses the relationship between normative theorizing and empirical justice research. Overall, this thesis integrates ideal and non-ideal normative theorizing, economic analysis, empirical justice research and hints at institutional implementation in the debate on sustainability and justice.
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.
This doctoral thesis contributes to the vibrant discourse on boundary-crossing collaboration in the German teacher education system. It offers theoretical advancements, programmatic guidelines, and empirical findings which advocate for a transdisciplinary perspective. In order to do so, the framing paper critically links persistent challenges and current reform processes in the teacher education system with theoretical foundations and conceptual positions of transdisciplinarity. Against this backdrop, four articles provide further insights on: a) how to expand the prevalent systematic of innovation and transfer approaches (top-down, bottom-up, cooperative) by a transdisciplinary perspective, b) outlining guiding principles for the realization of transdisciplinary collaboration in the context of a boundary-crossing research and development project, c) providing empirical findings on effect relationships between transdisciplinary dimensions of integration characteristics, and d) identifying empirical types of actors based on specific assessment patterns towards these characteristics.
Woman, Stand Straight: An Integrated Lutheran Feminist Theological Concept of Human Flourishing
(2022)
Beginning with the theology of Martin Luther and drawing on a selection of feminist theologians, this thesis proposes a relational, agential model of human flourishing. It is rooted in Luther's doctrines of the hiddenness of God and of God’s alien and proper work in the lives of believers. Such an approach gives rise to questions concerning human freedom and agency, sin, and the nature of our relationship with God and with other persons. Many feminist theologies provide an inadequate account of sin and its effects on the person and their relationships. This thesis asserts that taking sin and its effects seriously is essential to developing a secure and healthy self, and a healthy relationship with God and other persons. It therefore proposes a reworked understanding of religious incurvature as a relational model of sin which supports the goal of human flourishing. This concept of the self curved either inwards, or towards another, speaks to the nature of sin in its traditional understanding of sin as pride, as well as addressing feminist criticisms that the notion of sin as pride is not relevant to the needs and experiences of women. The model of human flourishing proposed here is specifically Christian in its assertion that we do not exist as persons, are not fully human, without our being in relationship with the triune God and other created persons. We flourish in community. Further, it supports the idea that true Christian freedom consists of a life dedicated to service of God and others.
The objective of the work described in this thesis is to improve our understanding of factors that affect the depletion of gaseous elemental mercury (GEM) from the atmosphere during the Arctic springtime. This was accomplished through research undertaken and described in three publications. Atmospheric mercury depletion events (AMDEs) are now an established phenomenon in the high Arctic whereby the long-lived GEM is oxidized in the air through a series of photochemically-initiated reactions involving halogens and ozone. This chemistry produces reactive gaseous mercury (RGM) and particulate bound mercury (PHg) which both have shorter atmospheric residence times than GEM and deposit more readily to the snow and ice surfaces. This is a means by which mercury can be transferred from the atmosphere to the Arctic environment that was unknown prior to 1995 when AMDEs were discovered. An extensive review paper was completed that summarizes mercury work in the high Arctic in the ten years following the discovery of AMDEs. This review was followed by two papers investigating the processes around atmospheric mercury in the Arctic springtime
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.
In response to the challenges of the energy transition, the German electricity network is subjected to a process of substantial transformation. Considering the long latency periods and lifetimes of electricity grid infrastructure projects, it is more cost-efficient to combine this need for transformation with the need to adapt the grid to future climate conditions. This study proposes the spatially varying risk of electricity grid outages as a guiding principle to determine optimal levels of security of electricity supply. Therefore, not only projections of future changes in the likelihood of impacts on the grid infrastructure were analyzed, but also the monetary consequences of an interruption. Since the windthrow of trees was identified a major source for atmospherically induced grid outages, a windthrow index was developed, to regionally assess the climatic conditions for windthrow. Further, a concept referred to as Value of Lost Grid was proposed to quantify the impacts related to interruptions of the distribution grid. In combination, the two approaches enabled to identify grid entities, which are of comparably high economic value and subjected to a comparably high likelihood of windthrow under future climate conditions. These are primarily located in the mid-range mountain areas of North-Rhine Westphalia, Baden-Württemberg and Bavaria. In comparison to other areas of less risk, the higher risk in these areas should be reflected in comparably more resilient network structures, such as buried lines instead of overheadlines, or more comprehensive efforts to prevent grid interruptions, such as structural reinforcements of pylons or improved vegetation management along the power lines. In addition, the outcomes provide the basis for a selection of regions which should be subjected to a more regionally focused analysis inquiring spatial differences (with respect to the identified coincidence of high windthrow likelihoods and high economic importance of the grid) among individual power lines or sections of a distribution network.
Online advertising has become one of the most important dimension of corporate communications. In recent years, a new form of advertising on the Internet has emerged: real-time advertising. Among others, it allows companies to identify potential customers and target them with respect to their interests. In this way, real-time advertising can increase advertising effectiveness and it could, at the same time, improve user experience. With the emerge of this new form of advertising, statistical models have become even more important because they are now being increasingly used to predict online user behavior. The articles included in this dissertation analyze user-level clickstream data generated during multi-channel advertising campaigns (including TV advertising) and during real-time auctions. The goal of the analyses conducted here is to better understand advertising effects and to support decision-making in this context. Most of the analyses are based on Bayesian models. These models allow for a very flexible structure, which enables researchers to model, for instance, heterogeneity across different types of users or non-linear parameters such as users´ reaction times and exponential decay of advertising effects. In addition, these models allow for the inclusion of prior knowledge of parameter distributions, and, therefore, they are well suited for iterative analyses based on clickstream data. Bayesian models can be evaluated in different ways. Instead of only relying on statistical metrics, the articles included in this dissertation aim to estimate the economic value of these models based on their predictive performance. Although this measure can only approximate their true economic value, this approach can be used to compare and evaluate different models and to illustrate the impact of predictive analyses for companies in the context of big data. This dissertation contributes to both information systems research and marketing research and has many managerial implications. First, a process is developed to determine optimal sample sizes representing the best balance between computational costs and predictive accuracy in e-commerce in particular and big data contexts in general. In practice, this process can be used to reduce infrastructure and computational costs. Second, the articles included here describe models that can be used to measure the impact of television ads on users' online shopping behavior. The models can provide insights concerning the effectiveness of individual television ads, the interactions between different advertising channels and the difference in user behavior of TV-induced customers and their non-TV-induced counterparts. Thereby, the models could support decision-making with respect to future advertising campaigns and targeting. Third, the articles describe several possibilities to extend and improve decision support systems currently used in e-commerce and marketing. These improvements enable practitioners to predict users´ interests for arbitrary products and services by using corresponding websites as dependent variables. This approach can be used to improve the effectiveness of real-time advertising campaigns, especially those intended to raise brand awareness among customers.
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.