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The wide accessibility of the Internet and web-based programs enable an increased volume of online interventions for mental health treatment. In contrast to traditional face-to-face therapy, online treatment has the potential to overcome some of the barriers such as improved geographical accessibility, individual time planning, and reduced costs. The availability of clients' treatment data fuels research to analyze the collected data to obtain a better understanding of the relationship among symptoms in mental disorders and derive outcome and symptom predictions. This research leads to predictive models that can be integrated into the online treatment process to assist clinicians and clients. This dissertation discusses different aspects of the development of predictive modeling in online treatment: Categorization of predictive models, data analyses for predictive purposes, and model evaluation. Specifically, the categorization of predictive models and barriers against the uptake of mental health treatment are discussed in the first part of this dissertation. Data analysis and predictive modeling are emphasized in the second part by presenting methods for inference and prediction of mood as well as the prediction of treatment outcome and costs. Prediction of future and current mood can be beneficial in many aspects. Inference of users' mood levels based on unobtrusive measures or diary data can provide crucial information for intervention scheduling. Prediction of future mood can be used to assess clients' response to the treatment and expected treatment outcome. Prediction of the expected treatment costs and outcomes for different treatment types allows simultaneous optimization of these objectives and to increase the cost-effectiveness of the treatment. In the third part, a systematic predictive model evaluation incorporating simulation analyses is demonstrated and a method for model parameter estimation for computationally limited devices is presented. This dissertation aims to overcome the current challenges of predictive model development and its use in online treatment. The development of predictive models for varies data collected in online treatment is demonstrated and how these models can be applied in practice. The derived results contribute to computer science and mental health research with client individual data analysis, the development ofpredictive models, and their statistical evaluation.
Establishing the identity of asylum seekers in the absence of credible documents represents a significant challenge for governments. To support decision-making processes in identity determination and verification procedures, Germany’s Federal Office for Migration and Refugees introduced three digital identification systems under the “Integrated Identity Management - plausibility, data quality and security aspects (IDMS)” programme. Because these algorithmic systems are deployed in highly political settings affecting vulnerable populations on the move, this research investigates how the Federal Office legitimises the policy and use of IDM-S that indicate a new direction of governance driven by so-called “innovative technologies”. In this context, legitimacy - considered a core virtue of just, democratic institutions - is understood as a justificatory concept seen in conjunction with (good) governance and the right to privacy as guaranteed under Article 17 of the International Covenant on Civil and Political Rights. The data justice framework is applied to structure the evaluation of state practices. In addition, the qualitative content analysis is used to find patterns in publicly available documents. Expert interviews were carried out to include experiences of affected individuals and to verify identified information provided by the government. The analysis revealed that efforts to legitimise IDM-S included four patterns: referring to the rule of law and national security concerns, non-disclosing delegitimising information and limiting accountability, emphasising performance efficiency and the systems’ high level of innovation, implying objective operations by means of a mathematical-technical approach. The results underscore profound discrepancies between justifications and state practices, outlining severe privacy violations as well as the lack of compliance to qualitative values in governance that pertain to participation, transparency, accountability, impartiality and scientific soundness of state operations.
Despite growing research on sustainability transformations, our understanding of how transformative transdisciplinary research can support local actors who foster change towards sustainability is still somewhat limited. To contribute to this research question, the investigator conducted research in a transdisciplinary case study in Southern Transylvania, where non-governmental organizations (NGO) drive sustainability initiatives to foster desired changes (e.g., supporting small-scale farmers or conserving natural and cultural heritage). Interactions with these local actors and reflections on the research question shaped the research of this dissertation. In paper 1, the author conducted a literature review on amplification processes that describe actions, which local actors can apply to increase the impact of their sustainability initiatives. In paper 2, he conducted a literature review on the application of indigenous and local knowledge (ILK) in sustainability transformations research to understand whether this research engages with the conceptualization of transformations from local actors. The results show that ILK is generally applied to confirm and complement scientific knowledge in contexts of environmental, climate, social-ecological, and species change. In paper 3, the author derived principles that provide guidance for how to integrate sustainability initiatives from local actors in transformative transdisciplinary research. Based on his transdisciplinary research with the NGOs in Southern Transylvania and by using systems and futures thinking as an approach for analysis, he derived three principles that provide guidance for the co-design of sustainability intervention strategies that build on, strengthen, and complement existing initiatives from local actors. In paper 4, the author explored empirically how to identify relevant local actors for collaborations that seek to intervene in specific characteristics of a system (e.g., parameters or design of a system). He applied a leverage points' perspective to analyse the social networks of the NGOs in Southern Transylvania that amplify the impact of their initiatives. This dissertation as a whole contributes insights to three recommendations of how transformative transdisciplinary research can support local actors fostering change towards sustainability: First, by conducting research that studies and supports local actors who increase the impact of their sustainability initiatives via amplification processes (Paper 1 and 4); Second, by engaging specifically with the initiatives, networks, and knowledge from local actors, who foster bottom-up, place-based transformations (Paper 1-4); Third, by identifying and collaborating with local actors that are relevant for strategic systems interventions that build on, strengthen, and complement existing initiatives (Paper 3-4).
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.
This thesis analyses how European merger control law is applied to the energy sector and to which extent its application may facilitate the liberalisation of the electricity, natural gas and petroleum industries so that only these concentrations will be cleared that honour the principles of the liberalisation directives. After having discussed the complex micro- and macro-economic considerations which accompany any concentration of business activities, this thesis discusses the merger control regime of the European Community (EC) so as to establish whether the merger control under either Art. 66 Treaty Establishing the European Coal and Steal Community (ECSCT), the case law under Art. 101 and 102 Treaty on the functioning of the European Union (TFEU) and (Art. 81 and Art. 82 Treaty Establishing the European Economic Community (ECT), as it was introduced by the Commission and reviewed by the CJEU, the original Merger Regulation (MR1989) or the amended Merger Regulation of 1997 (MR1997) or the amended Merger Regulation of 2004 (MR2004) facilitate the liberalisation of European electricity and gas markets. Said liberalisation was introduced by the Internal Electricity Market Directive (IEMD), the Hydrocarbons Licensing Directive and the Internal Gas Market Directive (IGMD). The paper focuses on the contestable idea that regulatory amendments - especially the introduction of third party access by means of the directives - only form a first necessary condition for attaining economic alterations whereas pro-active conduct of the marketers is the second and decisive one in order to increase the competitive performance of the European energy supply industries. The analysis is supported by a second argument which relates closely to the ambivalent nature of concentrations: A concentration may be used to increase the process of market opening and the expansion into new markets by pooling of scarce resources. It may also be used as a retro -active means so as to create national champions, increase barriers to market entry of new competitors, enable cross-subsidisation so as to expand dominant positions on heretofore competitive up- and downstream markets.
Viable communication systems
(2020)
Society has come to the point that it requires a "Great Transformation" towards sustainability to ensure the viability of the planet for a vital society. The energy transition plays a central role for this transformation. For transforming the patterns of energy production and use in an energy transition as part of the "Great Transformation", this process of change now needs to strengthen its focus on information, communication, and knowledge systems. Human society needs to establish a knowledge system that has the potential to create usable knowledge for sustainability solutions. This requires organizing a communication system that is sufficiently complex, interconnected, and, at the same time, efficient for integrating reflexive, open-ended, inter- and transdisciplinary learning, evaluation, and knowledge co-production processes across multiple levels. This cumulative dissertation contributes to research in this direction by applying a systemic sustainability perspective on the content and organization of communication in the field of research on sustainable energy and the operational level of municipal climate action as part of the energy transition. Regarding sustainability, this thesis uses strong sustainability and its principles as a frame for evaluating the content of communication. Regarding the systemic perspective, the thesis particularly relies on the following theories: (i) the human-environment system model by R. Scholz as an overarching framework regarding interactions between humans and nature, (ii) social systems theory by N. Luhmann to reflect the complexity of society, (iii) knowledge management to consider the human character of knowledge and a practice-oriented perspective, and (iv) management cybernetics, in particular, the Viable System Model by S. Beer as a framework to analyze and assess organizational structures. Furthermore, the thesis leverages the potential of text mining as a method to identify and visualize patterns in texts that reflect prevalent paradigms in communication. The thesis applies the above conceptual and methodological basis in three case studies. Case Study 1 investigates the measures proposed in 16 municipal climate action plans of regional centers in Lower Saxony, Germany. It uses a text mining approach in the form of an Summary interpretation network analysis. It analyzes how different societal subsystems are connected at the semantic level and to what extent sustainability principles can be recognized. Case Study 2 analyzes and reflects paradigms and discursive network structures in international scientific publications on sustainable energy. The study investigates 26533 abstracts published from 1990 to 2016 using a text mining approach, in particular topic modeling via latent Dirichlet allocation. Case Study 3 turns again to the cases of municipal climate action in Lower Saxony examined in Case Study 1. It examines the involvement of climate action managers of these cities in multilevel knowledge processes. Using design principles for knowledge systems, it evaluates to what extent knowledge is managed in this field across levels for supporting the energy transition and to what extent local innovation potential is leveraged or supported. The three case studies show that international research on sustainable energy and municipal climate action in Germany provide promising contributions to achieve a transformation towards sustainability but do not fully reflect the complexity of society and still support a growth paradigm, in contrast to a holistic sustainability paradigm. Further, the case studies show that research and local action are actively engaging with the diversity of energy technologies but are lagging in dealing with the socio-epistemic (communication) system, especially with regard to achieving cohesion. Using the example of German municipalities, Case Studies 1 and 3 highlight the challenges of achieving coherent local action for sustainability and bottom-up organizational learning due to incomplete or uncoordinated multilevel knowledge exchange.
Contemporary liberal-democracies are under stress and traditional political parties have become detached from their electorates. Since the 1980s, parties have been experiencing a crisis of legitimation, whose effects have become intensive especially in the early twenty-first century. New populist challengers have tried to fill the representative void left by mainstream parties; at the same time, technocracy has become one of the most prominent form of representation. Political responsibility and responsiveness appear often incompatible in the eyes of voters. Moreover, political personalization and processes of presidentialization have led to a situation where single political leaders have become the crucial political actors, to the detriment of party organizations. This Habilitation thesis investigates the linkage between representative democratic institutions in parliamentary and semi-presidential systems and political elites, trying to understand how this linkage has been affected by the change of party democracy. In particular, the thesis analyzes political institutions’ functioning in democratic contexts as well as parties’ responses and elites’ paths to power as indicators of a process of adaptation. Four main research questions inform the analysis: what structural opportunities and constraints do political elites meet when it comes to exercising political power?; how have the decline of party government and political personalization modified opportunity structures?; how do parties and elites cope with democratic change?; has democratic change produced new criteria for successful political careers? The institutional focus is on political executives and representative assemblies at different levels of government. Findings highlight that political elites adopts strategies of resistance and respond to democratic change through incremental steps. In other words, rather than anticipatory, political elites appear reactive, when they are confronted with substantial modifications of the political opportunity structure. Overall, the study contributes to the debate about the changing role of parties and political elites as connectors between the state and the society and provides insights about future developments.
Both sustainability and transdisciplinary research can change academic research, especially with regard to its relevance for, and relationship with, its environments. Transdisciplinary sustainability research (TSR), thus, offers the opportunity to change non-sustainable development paths of sciences themselves. In order to fully exploit this possibility, this PhD project addresses the question of how TSR, in the first place, does conceptualize and, in the second place, could conceptualize knowledge, research, and science. Firstly, this PhD project analyzes, from a discourse studies perspective, the term problem in TSR, against the background of discourses on sustainable development. Secondly, it explores the historical-analytical and transformative concept of the problematic. The results, firstly, show the consequences of a problem-solving focus for TSR, and secondly, differentiate it from a transformative direction of problematic designing, as a more appropriate view on the dimensions of transformation and their qualities of change that matter for TSR. This PhD project aims to contribute to a self-understanding of, and a philosophical communication about, TSR, as a research form in the sustainability sciences.
Personally meaningful tourist experiences foster subjective mental wellbeing. Modern, human-centred technologies such as gamified technology have been recognised as a promising means to support tourists in their co-creation of meaningful tourist experiences. However, a deeper understanding and conceptualisation of tourists' engagement with gamified technologies in the tourist experience has remained absent so far. This study draws on positive psychology as the guiding theoretical lens to conceptualise and explore tourists' underlying motives for engaging with gamified technology, as well as the gratifications thereof for the tourist experience. In doing so, this thesis identifies how tourists generate meaning through interacting with gamified technology in the tourist experience, thereby fostering the co-creation of meaningful tourist experiences and contributing to subjective mental wellbeing. Being among the first studies to link the concepts of positive psychology, gamified technology, and tourist experiences, the results of this thesis provide rich findings on the underlying motives for tourists to engage with gamified technology during vacation, as well as the gratifications of gamified technology for the creation of meaning in the tourist experience. Using the theoretical lens of positive psychology and achievement motivation theory as the main theoretical underpinning, this study is positioned at the intersection of social psychology, human-computer interaction, and tourism as the field of application. Conceptually, this thesis provides an in-depth understanding of tourists’ engagement with gamified technology, including the socio-psychological motivators for engagement and the outcomes thereof for the tourist experience.
It is understood among research and policy makers that addressing unsustainable individual consumption patterns is key for the vision of sustainable development. Education for Sustainable Consumption (ESC) is attributed a pivotal role for this purpose, aiming to improve the capacity of individuals to connect to and act upon knowledge, values and skills in order to respond successfully and purposefully to the demands of sustainable consumption. Yet despite political, scientific, and educational efforts and increasing awareness in the general population, little has been achieved to substantially change behavioral patterns so far. As part of the explanation for this shortcoming, it has been argued that current ESC practices have neglected the personal dimension of sustainable consumption, especially the affective-motivational processes underlying unsustainable consumption patterns. Against this background, this cumulative thesis is guided by the question how personal competencies for sustainable consumption can be defined, observed, and developed within educational settings. Special attention is given to mindfulness practices, describing the practice of cultivating a deliberate, unbiased and openhearted awareness of perceptible experience in the present moment. Drawing upon an explorative, qualitative research methodology, the thesis looks at three different mindfulness-based interventions aiming to stimulate competencies for sustainable consumption, reaching out to a total number of 321 participants (employees and university students). In this thesis, the author suggests to define personal competencies for sustainable consumption as abilities, proficiencies, or skills related to inner states and processes that can be considered necessary or sufficient to engage with sustainable consumption (SC). These include ethics, self-awareness, emotional resilience, selfcare, access to and cultivation of personal resources, access to and cultivation of ethical qualities, and mindsets for sustainability. The thesis holds that the observation of personal competencies benefits from a combination of different methodological and methodical angles. When working with self-reports as empirical data, a pluralistic qualitative methods approach can help overcoming shortcomings that are specifically related to individual methods while increasing the self-reflexivity of the research. Moreover, it is suggested to let learners analyze their own personal statements in groups, applying scientific methods. The products of the group analyses represent data based on an inter-subjectively shared perspective of learners that goes beyond self-estimation of personal competencies. In terms of developing personal competencies for SC, it can be concluded that mindfulness practice alone is not sufficient to build personal competencies for SC. While it can stimulate generic personal competencies, individuals do not necessarily apply these competencies within the domain of their consumption. Nevertheless, mindfulness practice can play an important role in ESC, insofar as it lays the inner foundation to engage with sustainability-related issues. More precisely, it allows learners to experience the relevance of their inner states and processes and the influence they have on actual behaviors, leading to a level of selfawareness that would not be accessible solely through discursive-intellectual means. Furthermore, participants experience mindfulness practice as a way to develop ethical qualities and access psychological resources, entailing stronger emotional resilience and improved well-being. In order to unleash its full potential for stimulating personal competencies for SC, however, the findings of the thesis suggest that mindfulness practice should be (a) complemented with methodically controlled self-inquiry and (b) related to a specific behavioral change. In this vein, self-inquiry-based and self-experience-based learning – two pedagogical approaches developed during the period of research for this thesis – turned out to be promising pedagogies for educational settings striving to stimulate the development of personal competencies for SC.
The dissertation contains four journal articles which are embedded within a framework manuscript that interconnects the individual articles and provides relevant background information. The dissertation's overall objective is to provide a multilayered and critical in-depth engagement with the timely phenomenon of integrated reporting (IR), a new reporting concept that is envisaged to revolutionize firms' present reporting infrastructure. While extant corporate reports (e.g., annual financial- and CSR report) often are criticized for being disconnected and to suffer from a lack of coherence, IR intends to provide all information that is material to a firm's short-, medium- und long-term value creation within one single, succinct document. To contribute to a set of previously defined relevant research gaps in literature, the dissertation makes use of a combined empirical-quantitative and explorative-qualitative research design. The first article entitled investigates a set of different IR-, corporate governance and financial accounting-specific factors that are expected to determine European and South African firms' materiality disclosure quality. To this purpose, an original, hand-collected materiality disclosure score was developed. The second article explores IR perceptions of SME managers that have not embarked on IR, but are potential candidates to do so in future. Based on a review of extant literature, the article develops a theoretical framework to subsequently discuss motives for and barriers to IR adoption. The critical discussion contributes to the academic debate on incentives for and barriers to voluntary IR adoption. The third article investigates whether voluntary IR adoption among European firms is associated with lower cost of public debt. While earlier studies suggest that IR leads to lower information asymmetries, increases analyst forecasts, and decreases cost of equity, corresponding evidence for the debt market is largely missing. Subsequent analyses test as to whether such an association is even more pronounced by a firm's environmental, social and governance (ESG) performance or its belonging to an environmentally sensitive industry. The fourth article uses an experimental design to investigate nonprofessional investors' reactions to an IR assurance. To this purpose, two separate experiments with two different groups of nonprofessional investors were carried out: one with Masters students and one with managers of large corporations. Results help to answer the question as to whether an IR assurance as well as its determinants, namely the assurance provider and the assurance level, affect nonprofessional investors' financial decision-making. In the second step, subsequent in-depth interviews reveal an IR assurance-critical attitude among managers, who draw upon their practical experience with assurance engagements.
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.
Many fewer women than men try the entrepreneurial way in Germany. Any explanation for this phenomenon must be complex, as many factors are relevant for its production. Among other things, it is possible to speculate on sexual/gender discrimination, on more or less voluntary decisions of women or on different starting conditions for potential entrepreneurs. We assume that these options are closely related. This paper will concentrate, though, on the third alternative. Its focus will be set on the “family field,” or more precisely, on the role of family law in hindering women from trying self-employment. The family field in Germany has not evolved in the sense of gender equality along with all other areas of society - e.g., entrepreneurship. No gender equality is possible if the family field is not part of it. This paper analyses causes and consequences for this phenomenon.
Key Words: Gender studies, Family Law, Entrepreneurship, chance equality, social sustainability
Comparable collaborations between farmers and institutions with communal catering have been less in research focus so far. Within the region of Lüneburg, an example for such a regional-organic cooperation is not known yet. Thus,this work represents the starting point to fill the research gap within the field of sustainable food systems in urban living labs as part of the research project GLOCULL (Globally and Locally-sustainable food-water-energy innovation in Urban Living Labs). The work aims at building up such a regional-organic food cooperation between a local farmer and a kindergarten community catering servicebased on scientific insights and practical persons’ knowledge.
In theory we pursue a sustainable development, but in reality we do not. An economy based on continuous growth, which evidently is not sustainable, is however the priority model almost everywhere. If we really aim at implementing sustainability, then we must radically change our economic model. Sufficiency - which calls for individuals mainly from so-called “developed countries” not to consume more than is really needed - may offer a useful alternative. We can still find some - last - examples of indigenous peoples living in a sufficient manner, all of them nowadays in those “developing countries”. We could learn at least from them that it is possible to live differently, i.e., in harmony with ourselves and our environment. This would pave the way for their - and for our all - protection, as well as the manner in which we understand at present development politics.
As modern society progresses, waste treatment becomes a pressing issue. Not only are global waste amounts increasing, but there is also an unmet demand for sustainable materials (e.g. bioplastics). By identifying and developing processes, which efficiently treat waste while simultaneously generating sustainable materials, potentially both these issues might be alleviated. Following this line of thought, this dissertation focuses on procedures for treatment of the organic fraction of waste. Organic waste is a suitable starting material for microbial fermentation, where carbohydrates are converted to smaller molecules, such as ethanol, acetic acid, and lactic acid. Being the monomer of the thermoplastic poly-lactic acid, lactic acid is of particular interest with regard to bioplastics production and was selected as target compound for this dissertation. Organic waste acted as substrate for non-sterile batch and continuous fermentations. Fermentations were initiated with inoculum of Streptococcus sp. or with indigenous consortium alone. During batch mode, concentration, yield, and productivity reached maximum values of 50 g L−1, 63%, and 2.93 g L−1 h −1. During continuous operation at a dilution rate of 0.44 d−1, concentration and yield were increased to 69 g L−1 and 86%, respectively, while productivity was lowered to 1.27 g L−1 h −1 . To fully exploit the nutrients present in organic waste, phosphate recovery was analyzed using seashells as adsorbent. Furthermore, the pattern of the indigenous consortium was monitored. Evidently, a very efficient Enterococcus strain tended to dominate the indigenous consortium during fermentation. The isolation and cultivation of this consortium gave a very potent inoculum. In comparison to the non-inoculated fermentation of a different organic waste batch, addition of this inoculum lead to an improved fermentation performance. Lactic acid yield, concentration, and molar selectivity could be increased from 38% to 51%, 49 g L−1 to 65 g L−1, and 46% to 86%, respectively. Eventually, fermentation process data was used to perform techno-economic analysis proposing a waste treatment plant with different catchment area sizes ranging from 50,000 to 1,000,000 people. Economically profitable scenarios for both batch and continuous operation could be identified for a community with as few as 100,000 inhabitants. With the experimental data, as well as techno-economic calculations presented in this dissertation, a profound contribution to sustainable waste treatment and material production was made.
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.
Analysis of User Behavior
(2020)
Online behaviors analysis consists of extracting patterns from server-logs. The works presented here were carried out within the "mBook" project which aimed to develop indicators of the quantity and quality of the learning process of pupils from their usage of an eponymous electronic textbook for History. In this thesis, the research group investigates several models that adopt different points of view on the data. The studied methods are either well established in the field of pattern mining or transferred from other fields of machine learning and data mining. The authors improve the performance of archetypal analysis in large dimensions and apply it to unveil correlations between visibility time of particular objects in the e-textbook and pupils' motivation. They present next two models based on mixtures of Markov chains. The first extracts users' weekly browsing patterns. The second is designed to process essions at a fine resolution, which is sine qua non to reveal the significance of scrolling behaviors. The authors also propose a new paradigm for online behaviors analysis that interprets sessions as trajectories within the page-graph. In this respect, they establish a general framework for the study of similarity measures between spatio-temporal trajectories, for which the study of sessions is a particular case. Finally, they construct two centroid-based clustering methods using neural networks and thus lay the foundations for unsupervised behaviors analysis using neural networks.
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.
Technological development made it possible to store and process data on a scale not imaginable decades ago — a development that also includes network data. A particular characteristic of network data is that, unlike standard data, the objects of interest, called nodes, have relationships to (possibly all) other objects in the network. Collecting empirical data is often complicated and cumbersome, hence, the observed data are typically incomplete and might also contain other types of errors. Because of the interdependent structure of network data, these errors have a severe impact on network analysis methods. This cumulative dissertation is about the impact of erroneous network data on centrality measures, which are methods to assess the position of an object, for example a person, with respect to all other objects in a network. Existing studies have shown that even small errors can substantially alter these positions. The impact of errors on centrality measures is typically quantified using a concept called robustness. The articles included in this dissertation contribute to a better understanding of the robustness of centrality measures in several aspects. It is argued why the robustness needs to be estimated and a new method is proposed. This method allows researchers to estimate the robustness of a centrality measure in a specific network and can be used as a basis for decision making. The relationship between network properties and the robustness of centrality measures is analyzed. Experimental and analytical approaches show that centrality measures are often more robust in networks with a larger average degree. The study of the impact of non-random errors on the robustness suggests that centrality measures are often more robust if missing nodes are more likely to belong to the same community compared to missingness completely at random. For the development of imputation procedures based on machine learning techniques, a process for the evaluation of node embedding methods is proposed.
Existing institutions no longer appear to be sufficiently capable to deal with the complexity and uncertainty associated with the wicked problem of sustainability. Achieving the required sustainability transformation will thus require purposeful reform of existing institutional frameworks. However, existing research on the governance of sustainability of sustainability transformations has strongly focused on innovation and the more "creative" aspects of these processes, blinding our view to the fact that they go hand with the failure, decline or dismantling of institutions that are no longer considered functional or desirable. This doctoral dissertation thus seeks to better understand how institutional failure and decline can contribute productively to sustainability transformations and how such dynamics in institutional arrangements can serve to restructure existing institutional systems. A systematic review of the conceptual literature served to provide a concise synthesis of the research on "failure" and "decline" in the institutional literature, providing important first insights into their potentially productive functions. This was followed up by an archetype analysis of the productive functions of failure and decline, drawing on a wide range of literatures. This research identified five archetypical pathways: (1) crises triggering institutional adaptations toward sustainability, (2) systematic learning from failure and breakdown, (3) the purposeful destabilisation of unsustainable institutions, (4) making a virtue of inevitable decline, and (5) active and reflective decision making in the face of decline instead of leaving it to chance. Empirical case studies looking at the German energy transition and efforts to phase out coal in the Powering Past Coal Alliance served to provide more insights on (a) how to effectively harness "windows of opportunity" for change, and (b) the governance mechanisms used by governments to actively remove institutions. Results indicate that the lock-in of existing technologies, regulations and practices can throw up important obstacles for sustainability transformations. The intentional or unintentional destabilisation of the status quo may thus be required to enable healthy renewal within a system. This process required active and reflective management to avoid the irreversible loss of desirable institutional elements. Instruments such as "sunset clauses" and "experimental legislation" may serve as important tools to learn through "trial and error", whilst limiting the possible damage done by failure. Focusing on the subject of scale, this analysis finds that the level at which failure occurs is likely to determine the degree of change that can be achieved. Failures at the policy-level are most likely to merely lead to changes to the tools and instruments used by policy makers. This research thus suggests that failures on the polity- and political level may be required to achieve transformative changes to existing power structures, belief-systems and paradigms. Finally, this research briefly touches on the role of actor and agency in the governance of sustainabilitytransformations through failure and decline. It finds that actors may play an important role in causing a system or one of its elements to fail and in shaping the way events are come to be perceived.
Corruption as “the abuse of entrusted power for private gain” (Transparency International, 2013) is detrimental to economic, social and political development. It intensively violates the fundamental principles of democracy such as equality, fairness, transparency and accountability (Sandholtz and Taagepera, 2005). Europe exhibits a wide spectrum of corrupt activities and is characterized by large differences as to the extent and dynamics of corruption. Thus, it is astonishing that there is still little knowledge about the region-specific factors that determine corruption. Considering corruption as a multilevel phenomenon that takes place at the country level and is often measured by certain aggregated indices, this project examines corruption also at the individual level with data from the World Values Survey. The study includes 37 European countries at the macro level and 20 countries at the micro level (1995-2010). For comparative purposes and in order to uncover specific European determinants of corruption, all statistical calculations are run with an additional sample (“non-European country sample”), including countries world-wide. The results of the panel and multilevel analysis indicate that a country’s rate of inflation, international integration, the degree and duration of democracy, anti-corruption policy, the percentage of women in parliaments, religion, society’s history of corruption strongly influence the extent and dynamics of corruption at the country-level. At the individual level, an individual’s employment status, satisfaction with the financial situation, emancipative values, interpersonal trust and the justification of bribery are significant causes of corruption across and within European countries. A comparison of these results with the findings of the “world sample” clearly demonstrates that there are regional differences.
This cumulative dissertation embraces four empirical papers addressing socio-economic issues relevant to policy-makers and society as a whole. These papers cover important aspects of human life including health at birth, life satisfaction, unemployment periods and retirement decisions. The analyses are carried out applying advanced econometric methods and are based on data sets consisting of survey data as well as administrative records. The first joint paper investigates the causal impact of prenatal exposure to air pollution on neonatal health in Italy in the 2000s combining detailed information on mother's residential location from birth certificates with PM10 concentrations from air pollution monitors. Variation in local weekly rainfall is exploited as an instrumental variable for non-random air pollution exposure. Using quasi-experimental variation in rainfall shocks allows to identify the effect of PM10, ruling out potential bias due to confounder pollutants. The paper estimates the effect of exposure for both the entire pregnancy period and separately for each trimester to test whether the neonatal health effects are driven by pollution exposure during a particular gestation period. This information enhances our understanding of the mechanisms at work and help prevent pregnant mothers from most dangerous exposure periods. Additionally, the effects of prenatal exposure to PM10 are estimated by maternal labor market status and maternal education level to understand how the pollution burden is shared across different population groups. This decomposition allows to identify possible mechanisms through which environmental inequality reinforces the negative impact of early-life exposure to air pollution. This study finds that average PM10 and days with PM10 level above the hazard limit reduce birth weight, gestational age, and measures of overall newborn health. Effects are largest for third trimester exposure and for low-income and less educated mothers. The second joint paper updates previous findings on the total East-West gap in overall life satisfaction and its trend by using data from the German Socio-Economic Panel for the years 1992 to 2013. Additionally, the effects are separately analyzed for men and women as well as for four birth cohorts. The results indicate that reported life satisfaction is, on average, significantly lower in East than in West German federal states and that part of the raw East-West gap is due to differences in household income and unemployment status. The conditional East-West gap decreased in the first years after the German reunification and remained quite stable and sizable since the mid-nineties. The results further indicate that gender differences are small. Finally, the East-West gap is significantly smaller and shows a trend towards convergence for younger birth cohorts. The third joint paper explores the effects of a major reform of unemployment benefits in Germany on the labor market outcomes of individuals with some health impairment. The reform induced a substantial reduction in the potential duration of regular unemployment benefits for older workers. This work analyzes the reform in a wider framework of institutional interactions, which allows to distinguish between its intended and unintended effects. The results based on routine data collected by the German Statutory Pension Insurance and a Difference-in-Differences design provide causal evidence for a significant decrease in the number of days in unemployment benefits and increase in the number of days in employment. However, they also suggest a significant increase in the number of days in unemployment assistance, granted upon exhaustion of unemployment benefits. Transitions to unemployment assistance represent an unintended effect, limiting the success of a policy change that aims to increase labor supply via reductions in the generosity of the unemployment insurance system. The fourth, single-authored paper explores how an increase in the early retirement age affects labor force participation of older workers. The analysis is based on a social security reform in Germany, which raised the early retirement age over several birth cohorts to boost employment of older people and ultimately alleviate the burden on the public pension system. Detailed administrative data from the Federal Employment Agency allow to distinguish between employment and unemployment as well as disability pensions and retirement benefits claims. Using a Regression Kink design in a quasi-experimental framework, the author shows that the raised early retirement age had positive employment effects and negative effects on retirement benefits claims. The results also show that some population groups are more sensitive to a reduction in retirement options and more likely to seek benefits from other government programs. In this respect, the author finds that workers in manufacturing sector respond to the raised early retirement age by claiming benefits from the disability insurance program designed to compensate for reduced earnings capacity due to severe health problems. The treatment heterogeneity analysis further suggests that high-wage workers are more likely to delay exits from employment, which is in line with incentives but might also indicate an increased inequality within the affected birth cohorts induced by the reform. Finally, women seem to rely on alternative sources of income such as retirement benefits for women, or spouse's or partner's income not observed in the data. All things considered, workers did not adjust to the increased early retirement age by substituting early retirement with other government programs but rather responded to the reform in line with the policy intent. At the same time, the findings point to heterogeneous behavioral responses across different population groups. This implies that raising the early retirement age is an effective policy tool to increase employment only among older people who have the real choice to delay employment exits. Therefore, reforms that raise statutory ages should ensure social support for workers only marginally attached to the labor market or not able to work longer due to potential health problems or other circumstances.
This doctoral thesis contains four empirical studies analysing the personal accountability of prime ministers and the electoral presidentialisation of parliamentary elections in European democracies. It develops the concept of presidentialised prime ministerial accountability as a behavioural element in the chain of accountability in parliamentary systems. The ongoing presidentialisation of parliamentary elections, driven by changes in mass communication and erosion of societal cleavages, that fosters an increasing influence of prime ministers' and other leading candidates' personalities on vote choices, has called performance voting – and the resulting accountability mechanism of electoral punishment and reward of governing parties – into question. This thesis analyses whether performance voting can be extended to the personal level of parliamentary governments and asks whether voters hold prime ministers personally accountable for the performance of their government. Furthermore, it explores how voters change their opinion of prime ministers and how differences in party system stability and media freedom between Western and Central Eastern Europe contribute to higher electoral presidentialization in Central Eastern European parliamentary elections. This thesis relies on several national data sources: the "British Election Study", the "German Longitudinal Election Study" and other German election surveys, the "Danish Election Study", as well as, data from the "Forschungsgruppe Wahlen". In addition, it utilises cross-national data from the "Comparative Study of Electoral Systems".
Panic disorder is a common anxiety disorder, which is associated with high subjective burden as well as a high cost for the health economy. According to the National Treatment Guideline S3, cognitive behavior therapy is recommended as the most effective psychological treatment. However, many people in need do not have access to cognitive behavior therapy. Internet-based interventions have proven to be an effective way to provide access to evidence-based treatment to those affected. For anxiety disorders, such as panic disorder and agoraphobia, a good effectiveness of internet-based interventions has been proven in numerous international studies. However, the internet has changed over the last few years: mobile technologies have considerable potential to further improve the adherence and effectiveness of internet-based interventions. Against this background, the authors developed the hybrid online training "GET.ON Panic". In this training, an app has been integrated into a browser-based online training. The app consists of a mobile diary for self-monitoring as well as a mobile exposure-guide that supports participants in self-exposure exercises in their everyday lives.In an initial exploratory feasibility study, qualitative interview data and quantitative measurements were collected in a pre-post design of 10 participants. Usage, user friendliness, user satisfaction and acceptance of the app were generally considered high. The use of interoceptive exposure exercises and daily summaries of anxiety and mood were the most widely performed and rated the best, while in vivo exposure exercises and the monitoring of acute panic symptoms were found to be difficult.In the efficacy study, 92 participants with mild to moderate panic symptoms were randomized into two parallel groups. After eight weeks, the intervention group showed a significant improvement in the severity of panic symptoms compared to the waiting control group. Using the intention-to-treat approach, a covariance analysis with baseline values as a covariate yielded a mean effect of Cohen's d=0.66 in reducing the panic symptoms in favor of the intervention group. This effect increased to d=0.89 after three months and stayed at d=0.81 at the 6-month measurement point. Response and remission rates were also significantly higher in the intervention group. This positive effect was also shown for secondary outcomes such as depressive symptoms and quality of life. A correlation between app usage and clinical outcomes could not be found. This work was the first to demonstrate that a hybrid online training based on cognitive behavior therapy is effective in reducing panic symptoms as well as panic disorder. In addition, this work contributes to a deeper understanding of the potential of mobile technologies in the field of e-mental health.
Wind energy is expected to become the largest source of electricity generation in Europe's future energy mix. As a consequence, future electricity generation will be exposed to an increasing degree to weather and climate. With planning and operational lifetimes of wind energy infrastructure reaching climate time scales, adaptation to changing climate conditions is of relevance to support secure and sustainable energy supply. Premise for success of wind energy projects is the ability to service financial obligations over the project lifetime. Though, revenues(viaelectricity generation) are exposed to changing climate conditions affecting the wind resource, operating conditions or hazardous events interfering with the wind energy infrastructure. For the first time, a procedure is presented to assess such climate change impacts specifically for wind energy financing. At first, a generalised financing chain for wind energy is prepared to (qualitatively) trace the exposure of individual cost elements to physical climate change. In this regard, the revenue through wind power production is identified as the essential component within wind energy financing being exposed to changing climate conditions. This implies the wind resource to be of crucial interest for an assessment of climate change impacts on the financing of wind energy. Therefore, secondly, a novel high-resolution experimental modelling framework with the non-hydrostatic extension of the regional climate model REMO is set up to generate physically consistent climate and climate change information of the wind resource across wind turbine operating altitudes. With this setup, enhanced simulated intra-annual and inter-annual variability across the lower planetary boundary layer is achieved, being beneficial for wind energy applications, compared to state-of-the-art regional climate model configurations. In addition, surrogate climate change experiments with this setup disclose vertical wind speed changes in the lower planetary boundary layer to be indirectly affected by temperature changes through thermodynamically-induced atmospheric stability alterations. Moreover, air density changes are identified to occasionally exceed the net impact of wind energy density changes originating from changes in wind speed. This supports the consideration of air density information (in addition to wind speed) for wind energy yiel assumptions. Thirdly, the generated climate and climate change information of the wind resource are transferred to a simplified but fully-fledged financial model to assess the financial risk of wind energy project financing with respect to changing climate conditions. Sensitivity experiments for an imaginary offshore wind farm located in the German Bight reveal the long-term profitability of wind energy project financing not to be substantially affected by changing wind resource conditions, but incidents with insufficient servicing of financial obligations experience changes exceeding -10% to 14%. The integration of wind energy-specific climate and climate change information into existing financial risk assessment procedures would illustrate a valuable contribution to enable climate change adaptation for wind energy.
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.
Thermal energy storage systems have a high potential for a sustainable energy management. Low temperature thermochemical energy stores based on gas-solid reactions represent appealing alternative options to sensible and latent storage technologies, in particular for heating and cooling purposes. They convert heat energy provided from renewable energy and waste heat sources into chemical energy and can effectively contribute to load balancing and CO2 mitigation. At present, several obstacles are associated with the implementation in full-scale reactors. Notably, the mass and heat transfer must be optimized. Limitations in the heat transport and diffusions resistances are mainly related to physical stability issues, adsorption/desorption hysteresis and volume expansion and can impact the reversibility of gas-solid reactions. The aim of this thesis was to examine the energy storage and cooling efficiency of CaCl2, MgCl2, and their physical salt mixtures as adsorbents paired with water, ethanol and methanol as adsorbates for utilization in a closed, low level energy store. Two-component composite adsorbents were engineered using a representative set of different host matrices (activated carbon, binderless zeolite NaX, expanded natural graphite, expanded vermiculite, natural clinoptiolite, and silica gel). The energetic characteristics and sorption behavior of the parent salts and modified thermochemical materials were analyzed employing TGA/DSC, TG-MS, Raman spectroscopy, and XRD. Successive discharging/charging cycles were conducted to determine the cycle stability of the storage materials. The overall performance was strongly dependent on the material combination. Increase in the partial pressure of the adsorbate accelerated the overall adsorbate uptake. From energetic perspectives the CaCl2-H2O system exhibited higher energy storage densities than the CaCl2 and MgCl2 alcoholates studied. The latter were prone to irreversible decomposition. Ethyl chloride formation was observed for MgCl2 at room and elevated temperatures. TG-MS measurements confirmed the evolution of alkyl chloride from MgCl2 ethanolates and methanolates upon heating. However, CaCl2 and its ethanolates and methanolates proved reversible and cyclable in the temperature range between 25°C and 500°C. All composite adsorbents achieved intermediate energy storage densities between the salt and the matrix. The use of carbonaceous matrices had a heat and mass transfer promoting effect on the reaction system CaCl2-H2O. Expanded graphite affected only moderately the adsorption/desorption of methanol onto CaCl2. CaCl2 dispersed inside zeolite 13X showed excellent adsorption kinetics towards ethanol. However, main drawback of the molecular sieve used as supporting structure was the apparent high charging temperature. Despite variations in the reactivity over thermal cycling caused by structural deterioration, composite adsorbents based on CaCl2 have a good potential as thermochemical energy storage materials for heating and cooling applications. Further research is required so that the storage media tested can meet all necessary technical requirements.
To improve the properties of thermochemical heat storage materials, salt mixtures were evaluated for their heat storage capacity and cycle stability as part of the innovation incubator project "Thermochemical battery" of the Leuphana university Lüneburg. Based on naturally occurring compound minerals, 16 sulfates, 18 chlorides and 5 chloride multi-mixtures, 18 bromides and 5 intermixtures between sulfates, chlorides and bromides were synthesized either from liquid solution or by dry mixing for TGA/DSC screening before continuing the heat storage evaluation with five different measurement setups at a laboratory scale. The TGA/DSC analysis served as a screening process to reduce the number of testing materials for the upscaled experiments. The evaluation process consisted of a three-cycle dehydration/hydration measurement at Tmax=100°C and Tmax=200°C. In case of the bromide samples a measurement of hydration conditions with Tmax=110°C and a water flow at e=18.68mbar, were added to the procedure to detect the maximum water uptake temperature. Also, a single dehydration to a temperature of Tmax=500°C was implemented to observe melting behavior and to easier calculate the samples’ stages of hydration from the remaining anhydrous mass. Materials which showed high energy storage density and improved cycle stability during this first evaluation were cleared for multi-cycle measurements of 10 to 25 dehydration and hydration cycles at Tmax = 100 to 120°C and the evaluations at m=20 to 100g scale. An estimate for the specific heat capacities at different temperatures of the materials which passed the initial stage was calculated from the TGA/DSC results as well. The laboratory scale measurement setup went through five stages of refining, which led to reducing the intended maximum sample mass from m=100g to m=20g. A switch from supplied liquid water to water vapor as the used reactant was also implemented in exchange for improved dehydration conditions. Introducing a vacuum pump for evaporating the water limited the influence of outside heat sources during hydration and in-situ dehydration was enabled as to not disturb the state the samples were settling in between measurements. Baseline calculation from blanc measurements with glass powder and attempts to calculate the specific heat capacity cp of the tested materials by 6 applying the Joule-Lenz-law to the measurement apparatus was another step of method development. The evaluation process of the laboratory scale tests at the final setting consisted of 1 to 5 cycle measurements of in-situ dehydration and hydrations with applied vacuum for t=30 minutes at p~30mbar. Upscaling the sample mass to m=20g allowed for a close observation of different material behaviors. Agglomeration, melting and dissolving of the m=10mg samples during the TGA/DSC analysis can be deducted from the recorded measurement curves and the state of the sample after measurement. However, at laboratory scale the visible volume changes, observed sample consistency after agglomeration and an automatic removal of molten and dissolved sample mass during the measurement allowed for a better characterization and understanding of the magnitude of the actual changes. This was done for the first time, particularly for mixed salts. Of the original number of 62 samples, 4 mixtures which passed the initial TGA/DSC screening namely {2MgCl2+ KCl}, {2MgCl2+CaCl2}, {5SrBr2+8CaCl2} and {2ZnCl2 + CaCl2} were chosen for further evaluation. The multi-cycle TGA/DSC measurements of {2MgCl2+ KCl}, {2MgCl2+CaCl2} and {5SrBr2+8CaCl2} showed an improved cycle stability for all three materials over the untreated educts. Of the four materials {2ZnCl2 + CaCl2} displayed the strongest deliquescence during hydration in the upscaled experimental setup. {2MgCl2+CaCl2} proved to be the most stable material regarding the heat storage density. The {MgCl2} content of the mixture is likely to partially or completely react to {Mg(OH)Cl} at temperatures of T>110°C, which however does not impede the heat storage density. {5SrBr2+8CaCl2} displayed a low melting point in hydrated state, causing a fast material loss. This makes it an undesirable storage material. A lower heating rate may still help to avoid an early melting. The {2MgCl2+KCl} mixture was the most temperature stable of the mixtures showing no melting or dissolving behavior. A reaction of the {MgCl2} component of the mixture to {Mg(OH)Cl} was not observed within the applied temperature range of T=25 to 200°C.
Abstract As simple as it is, results describing the world are heavily dependent on the quality of the underlying data. One of the very crucial variables in microanalytical analyses of well-being and human resources is income. The more, when the situation of the self-employed is regarded. This paper focus on the distribution of income based on very sound data: the German Income Tax Statistic (Einkommensteuerstatistik) 1992. New is the actual possibility to use for the first time such a sound microdatabase to analyze the self-employed in particular: a 100.000 microdata sample of the population wide German Income Tax Statistic. New is the comparison between income from dependent and self-employed work with emphasis on the entrepreneurs and professions, and new is the indepth decomposition inequality analysis of the aggregated groups and of the single professions based on an inequality generalized entropy decomposition approach. One overall striking result is: the occupational status as an employee, entrepreneur or as a profession with its connected low between inequality share is by far not the overall driving factor to ‘explain’ the overall income distribution and inequality picture of the re-unified Germany; it is the within group inequality which counts in particular.
Climate change and atmospheric deposition of nitrogen affect biodiversity patterns and functions of forest ecosystems worldwide. Many studies have quantified tree growth responses to single global change drivers, but less is known about the interaction effects of these drivers at the plant and ecosystem level. In the present study, the authors conducted a full-factorial greenhouse experiment to analyse single and combined effects of nitrogen fertilization (N treatment) and drought (D treatment) on 16 morphological and chemical response variables of one-year-old Fagus sylvatica seedlings originating from eight different seed families from the Cantabrian Mountains (NW Spain). Drought exerted the strongest effect on response variables, reflected by decreasing biomass production. However, D and N treatments interacted for some of the response variables, indicating that N fertilization has the potential to strengthen the negative effects of drought (with both antagonistic and amplifying interactions). For example, combined effects of N and D treatments caused a sevenfold increase of necrotic leaf biomass. The authors hypothesize that increasing drought sensitivity was mainly attributable to a significant reduction of the root biomass in combined N and D treatments, limiting the plants' capability to satisfy their water demands. Significant seed family effects and interactions of seed family with N and D treatments across response variables suggest a high within-population genetic variability. In conclusion, the findings indicated a high drought sensitivity of Cantabrian beech populations, but also interaction effects of N and D on growth responses of beech seedlings.
This cumulative dissertation deals with the association between corporate governance, corporate finance and corporate tax avoidance in four scientific articles. The aim of this dissertation is to explain corporate tax avoidance by (a) focusing on corporate governance institutions as determinants of tax avoidance and (b) focusing on financial consequences of tax avoidance. Due to the close association between corporate governance and the concept of corporate social responsibility (CSR), the relationship between CSR and tax avoidance is also addressed. The first article using structured literature review methodology, analyzes extant research on the association between corporate governance and tax avoidance based on stakeholder-agency theory. However, also classical principal-agent theory is taken into account as its classical foundation. The first article identifies a number of open research questions and thereby serves as a theoretical basis for the subsequent articles. The second article also using structured literature review methodology, analyzes extant research on the association between CSR and tax avoidance. This article is also based on stakeholder-agency theory and identifies open research questions. The third article based on results of the first article, investigates tax avoidance by German private family firms as a specific variant of corporate governance, using an empirical quantitative approach. The article finds that (a) German private family firms avoid more tax than non-family firms, that (b) tax avoidance is positively associated with the capital stake of the family and that (c) tax avoidance is positively associated with the number of shareholders in both family and non-family firms. Results reinforce that corporate tax avoidance is associated to conflicts among the shareholders of private firms. The fourth article investigates the cost of debt of German public firms as a function of tax avoidance and tax risk. The article finds that (a) tax avoidance is negatively associated to the cost of debt, that (b) tax risk is positively associated to the cost of debt and that (c) the association between tax avoidance and the cost of debt becomes negative when a high level of tax risk is present.
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.
Global climate change and environmental degradation are largely caused by human activity, thus progress towards a sustainable future will require large-scale changes to human behavior. Human-nature connectedness (HNC) - a measure of cognitive, emotional, spiritual and biophysical linkages to natural places - has been identified as a positive predictor of sustainability attitudes and behaviors. While calls to "reconnect to nature" in order to foster sustainability outcomes have become common across science, policy and practice, there remains a great deal of uncertainty, speculation, and conceptual vagueness around how this ought to be implemented. The overarching aim of this thesis is to advance conceptual and empirical understandings of HNC as a leverage point for pro-environmental outcomes and sustainability transformation. In particular, the thesis attempts to assess the nuances of the HNC-PEB (pro-environmental behavior) relationship by investigating the scalar relationships between where someone feels connected to nature and where someone acts pro-environmentally. This research was conducted through conceptual exploration, systematic literature reviews using hierarchical cluster analysis, and empirical case studies relying on structural equation modeling and two-step cluster analysis. The relationship between HNC and pro-environmental attitudes and behaviors was investigated in a small microregion of Transylvania, Romania, where traditional relationships with the land and changing socio-economic characteristics provided an interesting case study in which to explore these connections. The key findings can be organized into three sections: Section A, which addresses HNC and its potential for sustainability transformation; Section B, which addresses HNC as a determinant of PEB outcomes, and Section C, which explores the relationships between human-nature connectedness and energy conservation norms, attitudes, and behaviors. Results cumulatively suggest that HNC is a multidimensional construct that requires greater integration across heterogeneous disciplinary and methodological boundaries in order to reach its potential for meaningful sustainability transformation. Results also highlight the critical need to adopt systemic approaches to understanding how interactions between human-nature connections, norms, attitudes, and behaviors are hindering or promoting sustainability outcomes.
Supporting sustainability transformation through research requires, in equal parts, knowledge about complex problems and knowledge that supports individual and collective action to change the system. Recasting the conditions, characteristics, and modes of research processes that address these needs leads to solution-oriented research in sustainability science. This is supported by systematically analyzing the system’s dynamics, envisioning the desired future target state, and by engaging and designing strategic pathways. In addition, learning and capacity building are important crosscutting processes for co-producing required knowledge. In research, we use sophisticated representations as mediators between theories and objects of interest, depicted as visualizations, models, and simulations. They simplify, idealize, and store large and dense amounts of information. Representations are already employed in the service of sustainability, e.g., in communication about climate change. Understanding them as tools to facilitate processes, dialogue, mutual learning, shared understanding, and communication can yield contributions to knowledge processes of analyzing, envisioning, and engaging, and has implications on the design of the sustainability solution. Therefore I ask, what role do representations and representational practices play in the generation of sustainability solutions in different knowledge processes? Four empirical case studies applying rough set analysis, multivariate statistics, systematic literature review, and expert interviews target this research question. The overall aim of this dissertation is to contribute to a stronger foundation and the role of representation in sustainability science. This includes: (i) to explore and conceptualize representations for the three knowledge processes along selected characteristics and mechanisms; (ii) to understand representational practices as tools and embedded into larger methodological frameworks; (iii) to understand the connection between representation and (mutual) learning in sustainability science. Results point toward crosscutting mechanisms of representations for knowledge processes and the need to build representational literacy to responsible design and participate in representational practices for sustainability.
To counteract species loss and preserve the remaining biodiversity, with its important ecosystem functioning and services essential to human well-being, there is an urgent need to develop promising and long-term conservation strategies. In order to achieve these goals, extensive research to gain a better understanding of the general mechanisms underlying community diversity is of greatest importance. Especially, the identification of intrinsic ecological and distributional species traits is receiving increased attention in ecology and conservation biology research. Depending on the expression of their traits, species perform particular ecosystem functions and respond in a specific manner to environmental conditions. Although insects make up the largest part of animal diversity, the majority of studies on extinctions have mainly focused on vertebrates. Among invertebrates either charismatic taxa or those targeted by conservation laws have been investigated until now (e.g. butterflies or saproxylic beetles). Being highly species-rich and trait-diverse, ground beetles (Coleoptera: Carabidae) should be even more suitable for conducting trait-based analyses. Thus, using ground beetles as a model taxon, four case studies focusing on the analyses of traits form the basis of this doctoral thesis. The work of this thesis was conducted with the aim of gaining general insights on the influence of species traits on ground beetle community compositions, such as habitat occupancy and species vulnerability to extinction, for instance. An important aspect when investigating species traits is the consideration of confounding factors, such as dependent relations between the different traits. Compiling a large dataset of 555 Central European species, the author identified that dependent relations between the six tested traits of ground beetles (distribution range size, habitat specialization, body size, hind-wing morphology, breeding season and trophic level) are highly common. Across all identified dependent trait relations, the relation between body size and hind wing morphology or range size and hind wing morphology showed the strongest significant dependencies. Since the consideration of trait relations is necessary to provide reliable interpretations, all analyses of this thesis tested several traits simultaneously and considered possible trait interactions. Studies on local communities found specific traits characterizing the local species pools of certain habitat types. Here, the species pools of seven different habitat types (coastal, forest, mountain, open, riparian, wetland and special habitat) were used to determine habitat-specific trait filters. The identified traits, characteristic for certain habitat types, were in most cases in accordance with the previous findings on local communities. Across Germany, the species of frequently disturbed habitat types, namely coastal, riparian and wetland habitats were characterized by small body size, high amount of macroptery, intermediate to high habitat specialization, spring breeding, and predatory feeding behavior. The species of stable habitat types (forest, mountain, and open habitats), however, were found to be generally larger in body size and more frequently breeding in autumn, further displaying greater variations in the other traits. The gained knowledge on the habitat-specific filtering of traits improve our understanding of the organization and assembly of communities, and can thereby help to detect alterations in the habitat-specific species pool due to natural or human-induced environmental changes. Furthermore, traits can provide evidence on species occurrences and vulnerability to extinction. Three case studies of this thesis aimed to gain new insights on this topic, through the investigations on the following research questions: (1) Which traits drive species extinction risks of Central European ground beetle species? (2) How traits influence the species occurrences of 28 forest species within a large area in Central Europe? (3) Whether certain traits are related to long-term population trends of the species pool from an ancient forest in northern Germany? The results indicated, that depending on the habitat type and tested species pool, different traits prove to be good predictors for the vulnerability of species. Nevertheless, across different geographical and taxonomical scales, especially species with small range sizes and high habitat specialization faced a greater risk of extinction. Therefore, the two traits distributional range size and habitat specialization emerge as reliable predictors of ground beetles vulnerability to extinction. Interestingly, body size did not display a consistent response; while increasing body size led to higher extinction risk in riparian, wetland and open habitats and large macropterous species showed higher extinction risks across the entire species pool, smaller species showed long-term population declines in an ancient forest.
"Sustainable development" evolves along the resolutions, declarations, and reports from international processes in the framework of the United Nations (UN). The consensual outputs from such processes feature global-generalised and context-free perspectives. However, implementation requires action at diverse and context-rich local levels as well. Moreover, while in such UN processes national states are the only contractual parties, it is increasingly recognised that other ("nonstate") actors are crucial to sustainability. The research presented here places the attention on bottom-up initiatives that are advancing innovative ways to tackle universal access to clean energy and to strengthen small-scale family farmers. This means, the focus is on bottom-up initiatives advancing local implementation of global sustainability targets, more precisely, targets that make part of the Sustainable Development Goals 2 and 7 (SDG 2 and SDG7). The research asks how such bottom-up initiatives can contribute to the diffusion of sustainability innovations, thereby also contributing to social change. Three aims are derived out of that central question: (1) To understand the role of bottom-up initiatives in the diffusion of sustainability innovations and in the thereby involved social changes. (2) To contribute with my research to the actual diffusion of sustainability innovations. (3) To outline a research approach that provides a solid conceptual and methodological framework for attaining the analytical and transformative aims. The doctoral research comprises four single studies, in which the notion of diffusion is explored at different scopes of social scales. It begins with a thorough analysis of diffusion programs of domestic biodigesters to rural households in countries of the global south. The focus is on the process by which this specific technical inno0vation results integrated (or not) into the daily realities of single rural households, that is, the adoption process. In the second study, the attention is on energy supply models based on different decentralised renewable technologies. Central to these models is the building of new (or strengthening of existing) local socioeconomic structures that can assume and ensure the proper operation and supply of energy services. The interest in this study is on the strategies that organisations implementing community-based energy projects apply to support the realisation of such local structures. The third study focuses on a network of bottom-up initiatives that have been advancing alternative approaches to family farming in Colombia. The network mainly comprises farmers associations, other organisations from civil society, and researchers who had been collaborating and experimenting with innovations in different innovation fields such as technical, organisational, financial, and commercialisation schemes. The aim of this third study is to provide insights into the challenges and difficulties faced by these actors in broadening the diffusion of the innovations they have been advancing. To perform this study, a methodological strategy is applied that combines a transdisciplinary mutual learning format with qualitative content analysis techniques. The fourth and last study is a conceptual disquisition. It develops a conceptual framework that (a) provides better accounts for the particularities of endeavours aimed at the diffusion of knowledge and practices from the bottom-up across local contexts and social scales, and (b) advances first conceptual steps towards an explicit account for the role that innovation research (and innovation researchers) can assume for the actual realisation of diffusion. The main findings or contributions of the doctoral research can be categorised into four subjects: 1) Bottom-up initiatives contribute to the diffusion of sustainable innovations by mobilising transformative resources for inducing diffusion in their scope of action and creating spaces for experimentation in which interventions can be tested (and if necessary adjusted) in order to ensure the proper deployment of innovations. 2) In their efforts to advance the diffusion of sustainability innovations, bottom-up initiatives contribute to social changes for ensuring the effective deployment of the innovations and building local available storage of transformative resources. 3) A conceptualisation of innovation diffusion, in which the work of academic researchers studying innovation is a constitutive part of transdisciplinary knowledge articulations that promote diffusion. In this way transdisciplinary research alliances can be envisioned in which researchers investigate about, with, and for bottom-up initiatives. 4) Contributions to the consolidation, systematisation, and dissemination of strategies that are applied by farmers associations in order to strength the economic, social, environmental, and cultural dimensions of Colombian family farmers.
The timber shortage led to large scale afforestations on previously agriculturally used land in Central Europe during the 19th and 20th century. Widespread afforestation programs created recent forest ecosystems (i.e. young forest systems in terms of their development history). Despite the positive effect of increasing the forest area of Central Europe, the ecological effects of these land-use changes on forest ecosystems remain poorly understood. In order to increase the understanding of ecosystem processes in forests, an assessment of conceivable shifts in ecosystem functions caused by former land-use changes and forest management is required. By analysing aboveground growth rates of European beech (Fagus sylvatica L.) in response to environmental change drivers, such as climate extremes and nitrogen (N) deposition, the presented thesis aims to assess the role of land-use and management legacies in modulating present responses to drivers of environmental change. To this end, annual radial growth rates of individual trees were measured in mature beech stands. The investigated stands differed either in their land-use history (i.e. ancient forest sites versus recent forests) or their forest management history (i.e. managed forest sites versus short-term and long-term unmanaged forest sites). Measurements of radial growth rates were complemented by analyses of the fine root systems, soil chemical properties and crown projection areas to gain insights into the mechanisms underlying alterations in tree growth. Within the projects of the presented thesis, shifts in the climate-growth relationships driven by land-use and management legacies were analysed. In addition, land-use legacy mediated differences in the climate-nitrogen-growth relationships were assessed. The key findings are: (I) Soil legacy driven alterations in the fine root systems cause a higher sensitivity of radial increment rates to water deficits in summer for trees growing on recent forest sites than for trees growing on ancient forest sites. (II) Management legacies (in terms of tree release) enhance the sensitivity of beech’s radial growth to water deficits in spring through changes in crown sizes. (III) Interacting effects of spring water deficits and co-occurring high deposition of reactive N compounds lead to stronger radial growth declines in trees growing in ancient forests. This is likely caused by resource allocation processes towards seed production, which is, in turn, mirrored by decreasing radial growth rates. In this context, high N deposition likely boosts mass fructification in beech trees. Overall, it has been demonstrated that the ecological continuity plays a crucial role in modulating both climate sensitivity and the growth response to interacting effects of water deficits and nitrogen deposition in beech trees. The presented thesis identified a trade-off between the climate sensitivity and maximised growth rates within beech trees, depending on forest history. The results show that the growth of beech in ancient, unmanaged beech forests is less sensitive to water deficits than in recent and managed beech forests. Additionally, interacting effects of spring water deficits and N deposition likely increase the reproductive effort of beech trees, particularly in ancient forests. Thus, the results of this thesis once again underpin the uniqueness of ancient, unmanaged beech forests, whose importance for the conservation of biodiversity has been widely acknowledged. In summary, the presented thesis highlights the need to consider the "ecological memory" of forest ecosystems when predicting responses to current and future environmental changes.
Increasingly, researchers are expected to work in collaborative interdisciplinary teams to tackle more complex and interrelated problems. However, the prospect of collaborating with others, from different disciplines, exerts countervailing forces on researchers. There is the lure of transcending the limitations of one's own knowledge, methods and conventions, belonging to diverse intellectual communities and tackling, together, ambitious research topics. On the other hand, there is the risk that collaborating across disciplinary boundaries will be taxing, confounding at times, with no guarantee of success. This thesis is about collaborative interdisciplinary research from the perspective of a formative accompanying researcher. The author accompanied an interdisciplinary research team in the field of sustainability over three years for the duration of a collaborative project. Formative accompanying research (FAR) is an approach to "research into research" that learns about, with and for a collaborative interdisciplinary team. The author found - through immersion in the literature, her own daily experiences of collaborating, and her observations – that interdisciplinary collaboration is very difficult. It requires a basic understanding and appreciation of other disciplines and methods, as well as the skills to integrate research inquiries and findings across diverse epistemologies. It also requires awareness that collaborative interdisciplinary research is more than an intellectual task of knowledge creation. Other factors matter, such as interpersonal relationships, power differentials, different research tempos and a sense of belonging. And these factors have an impact on processes and outcomes of collaborative knowledge creation. Knowing this implies a willingness to keep learning and to tolerate discomfort so as to cultivate deeper levels of collaborative capacity. The author discovered that in these deeper levels lie skills for staying with inevitable tensions, for talking and listening to generate new understanding together, and for applying a researcher's frank curiosity to oneself too. A formative accompanying researcher, who is part of the team she is researching, has to navigate delicate terrain. In this thesis, the author develops a FAR methodology that takes seriously the questions of positionality and relationality, and reflects on the experiences of putting these into practice. A FAR practice involves remaining in dynamic movement between observing and participating, between exercising curiosity and care, and between the researchers' own sense of impartiality and investment in relation to the issues at hand. There is merit in furthering the methodology and practice of FAR on its own terms. This includes attending to the skills required by a formative accompanying researcher to remain oriented within the concentric circles of research, relationship and loyalty that make up a collaborative team. There is also the question of how FAR, and other forms of research into research, can help to advance collaborative interdisciplinary research. The author argues for creating the conditions in research teams that would enable treating collaboration as a capacity to develop, and that would facilitate team members' receptivity to learning with FAR. Furthermore, she explores dilemmas of intervening as a formative accompanying researcher and of sustaining dynamic positionality over the long-term.
Decoding the psychological dimensions of human odor perception has long been a central issue of olfactory research. As odor percepts could not be linked to a few measurable physicochemical features of odorous compounds or physiological characteristics of the olfactory system, odor qualities have often been assessed by perception–based ratings. Although these approaches have been promising, none of the proposed system has sustained empirical validation. In a review of 28 studies, the authors assessed how basic characteristics of study design have been biasing perception–based classification systems: (1) interindividual differences in perceptual and verbal abilities of subjects, (2) stimuli characteristics, (3) approaches of data collection, and (4) methods of data analysis. Remarkably, many of the difficulties in establishing these systems have been rooted in one underlying issue: the puzzling relationship between language and olfaction in general. While the reference from odors to language is weak, the reverse impact of verbal processing on olfaction seems powerful. Odor perception is biased by verbal–semantic processes when cues of an odor's source are readily available from the context. At the same time, olfaction has been characterized as basically sensation driven when this information is absent. The authors examined whether language effects occur when verbal cues are absent and how expectations about an odor's identity shape odor evaluations. Subjects were asked to rate 20 unlabeled odor samples on perceptual dimensions as well as quality attributes and to eventually provide an odor source name. In a subsequent session, they performed the same rating tasks on a set of written odor labels that was compiled individually for each participant. It included both the 20 correct odor names (true labels) and – in any case of incorrect odor naming in the first session – the self–generated labels (identified labels). The authors compared odor ratings to ratings of both types of labels and found higher consistencies between the evaluation of an odor and its identified label than between the description of an odor and its true (yet not associated) label. These results indicate that basic perceptual as well as quality ratings are affected by semantic information about an odor's source – even in absence of source cues. That is, odor sensation may activate a semantic mental representation of an odorous object that affects odor processing and may in turn relate to further multimodal properties. That means, associations between odors and stimuli from other sensory modalities should not only be stable, but these mappings should be mediated by an odor’s identity. The authors asked subjects to visualize their odor associations on a drawing tablet, freely deciding on color and shape. Additionally, they provided a verbal label for each sample. Color mappings were odor-specific, they reflected the imagery of a natural source and seemed to change with assumed odor identity. Shape mappings changed with odor identifications as well, as drawings frequently displayed concrete objects that reflected visual features of an odor's source. The influence of verbal identity codes on quality ratings or crossmodal mappings is rooted in the very same problem that perception–based classification systems have tried to solve – a terminology that relates to abstract mental categories. The less specific we communicate, the more we need to resort to source–related analogies – in scientific endeavors and everyday life alike.
Neither market income nor consumption expenditure provides an adequate picture of individual standard of living. It is time which enables and restricts individual activities and is a further brick to a more comprehensive picture of individual wellbeing. In our study we focus on a prominent part of time use in non-market services: it is parental child care which contributes not only to individual but also to societal well-being. Within a novel approach we ask for multidimensional polarization effects of parental child care where compensation/ substitution of time for parental child care versus income is interdependently evaluated by panel estimates of societys subjective well-being. The new interdependent 2DGAP measure thereby provides multidimensional polarization intensity information for the poor and the rich and disentangles the single time and income contribution to subjective well-being ensuring at the same time the interdependence of the polarization dimensions. Socio-economic influences on the polarization pole risk and intensity will be quantified by two stage Heckman estimates. The analyses are based on the German Socio-Economic Panel with 21 waves and robust fixed effects estimates of subjective well-being as well as the German Time Use Surveys 1991/92 and actual 2012/13 with detailed diary time use data. The empirical results discover the interdependent relations between parental child care and income under a common evaluation frame and contribute to the question of dimension specific targeted policies in a multidimensional polarization approach. Prominent result: compensation between parental child care time and income proved to be significant, but there are multidimensional regions with no compensation, where parental child care time deficit is not compensated by income. Interdependent multidimensional polarization by headcount and intensity increased significantly over the twenty years under investigation with remarkable risk and intensity differences between the polarization poles with different disentangled parental child care time and income contributions to subjective well-being.
Quality of life and satisfaction with life are of particular importance for individuals as well as for society concerning the “demographic change” with now longer retirement periods. This study will contribute to the life satisfaction discussion and quantifies life satisfaction and pattern of explanation before and after such a prominent life cycle event, the entrance into retirement. In particular, with the individual longitudinal data and 33 waves of the Socio-Economic Panel (SOEP) and the appropriate microeconometric causal fixed effects robust panel methods we ask and quantify if actual life satisfaction indeed is decreasing before re-tirement, is increasing at the entrance into retirement, and is decreasing then after certain periods back to a foregoing level. Thus, we ask if such an anticipation and adaptation pattern– as known from other promi-nent events – is also to discover for life satisfaction before and after retirement in Germany. Main result: Individual and family situation lift life satisfaction after retirement for many years, the (former) occupational situation, however, absorbs this effect both for pensioners and civil service pensioners. It remains only one period of improvement with close anticipation and adaptation at entering retirement but no furthermore significant change compared to pre-retirement life satisfaction. This holds for pensioners (German pension insurance, GRV) but there is no significant effect at all for civil service pensioners.
On 25 October 2016, the European Commission presented a proposal for a directive on a Common Corporate Tax Base (CCTB Proposal), which contains a comprehensive concept for the harmonisation of profit calculation regulations within the EU. Against this current background, the objective of the present work is to contribute to the implementation of the CCTB by identifying ambiguities and conceptual weaknesses in the design of the profit determination system of the CCTB Proposal and developing concrete recommendations for action for adjustments in the course of the further legislative procedure. In the first article, selected profit calculation rules of the CCTB Proposal will be analysed in detail and compared with the provisions on profit calculation under German commercial and tax law and the International Financial Reporting Standards (IFRS) recognised across member states. Based on the legal comparison, questions of interpretation and inadequacies of the profit calculation system will be considered and proposals for adjustments to various regulatory areas will be submitted. Furthermore, in the second article, within the framework of a holistic study, expert interviews will be used as an empirical-qualitative research design to generate reliable assessments on the part of the various stakeholder groups affected by the implementation of the future directive or involved in its elaboration. The results show the extent to which the profit determination rules of the CCTB Proposal in their current form are suitable for national and EU-wide implementation and in which areas the various expert groups still see concrete need for adaptation. Based on these expert assessments, the third article finally develops a proposal to reduce the threat of legal uncertainty in interpretation issues criticised by the experts. Based on economic maxims developed by the European Commission and existing accounting principles of the current CCTB Proposal, the EU Accounting Directive and IFRS, a system of specific European tax principles will be developed which could be implemented within the framework of the CCTB Proposal.
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.
The dissertation analyzes the role of large banks in the context of financial (in)stability. Based on the underlying "too big to fail"-problem (TBTF), the three included papers investigate the reasons for the instability of banking systems on a national and international level. Already in advance, but at least since the years 2007/2008 with the escalation of the financial crisis, especially large banks are under critical supervision of regulators and the society. There exist numerous aspects that should to be taken into account when addressing TBTF which complicates the finding of a solution to the problem. In particular, the thesis investigates three major issues in this context: (1) The contribution of the size of a bank to the development of financial crises or the exposure of large banks to systematic risk and contagious spillovers. (2) The spillover effects from one banking system to another and the importance of banks' foreign asset holdings for the transmission of sovereign risk on foreign banks. (3) The impact of the degree of competition in the German banking market on the stability of the banking system.
Social insects like honeybees (Apis mellifera) and stingless bees (Apidae: Meliponini) face a relatively high risk to be attacked by pests and pathogens. To decrease the risk of infection, in addition to an innate immune system, these species have evolved various cooperative defense mechanisms which contribute to the overall health of the colonies and are therefore also referred to as social immunity. The collection and use of plant resin is another important strategy of social immunity. Resin is a sticky, often aromatic substance with antimicrobial and deterrent properties secreted by plants for protection of the vegetative tissue. Honeybees and stingless bees take advantage of these properties by using resins for nest construction (often mixtures of resin and wax called "propolis" or "cerumen") and as defense against pests and pathogens. Plant resins, thus, play a crucial role for the ecology of these species and are an important resource for them. Nevertheless, how bees exploit available resin sources and if resin collection can protect colonies from diseases received comparatively little attention in the past. Therefore the aim of this thesis is to provide new insights into the plant origin and significance as well as the influence of resin resource diversity on bee colony health. For honeybees (A. mellifera) in temperate regions, precise information about which resin sources they use is largely lacking. By chemical comparing bee-collected resins and tree resins, the researcher traced back the resin sources used by individual bees. Results show that honeybees collect distinct resin types that are related to different tree species (several poplar species: Populus balsamifera, P. xcanadensis; Betula alba; Aesculus hippocastanum; several poplar species). With this study, the author provided the first evidence, that A. mellifera in temperate regions use a variety of different tree species as resin sources and, moreover, show preferences for specific resin sources. Furthermore, the researcher conducted an experimental field study in which she investigated whether propolis, as it is naturally deposited in the nests, can protect honeybee colonies against some of the most important pathogens (Varroa destructor mite, Deformed Wing Virus). The results of this study showed that propolis in (semi-) natural conditions can increase the disease resistance of honeybee colonies, underscoring the importance of resins for honeybee health. Resin collection by stingless bees is comparatively well studied and it is known that these species commonly forage on a variety of different plant species. To increase knowledge on whether and how bees may profit from a diversity of resin resources, the researcheer tested how the protective function of a resin varied among different sources (and their mixtures) and various potential aggressors (predators, parasites and pathogens). The results of this study revealed that resins from different trees vary in their effectivity against different target organisms. Moreover, resin blends were more effective than some of the individual resins, suggesting that bees can benefit from a variety of resin resources. In summary, honeybees in temperate regions, similar to tropical stingless bees, use a variety of different tree species as resin sources. Because resins from different tree species varied in their protective function, this indicates that bees can profit from a variety of different resins/resin sources by improving the defense against diverse pests and pathogens. Conversely, the lack of resin had a negative impact on the disease resistance of colonies. Consequently, availability as well as the variety of suitable resin sources is of great importance for the health of bees.
Through the expansion of human activities, humanity has evolved to become a driving force of global environmental change and influences a substantial and growing part of natural ecosystem trophic interactions and energy flows. However, by constructing and building its own niche, human distance from nature increased remarkably during the last decades due to processes of globalization and urbanization. This increasing disconnect has both material and immaterial consequences for how humans interact and connect with nature. Indeed, many regions across the world have disconnected themselves from the productivity of their regional environment by: (1) accessing biological products from distant places through international trade, and (2) using non-renewable resources from outside the biosphere to boost the productivity of their natural environment. Both mechanisms allow for greater resource use then would be possible otherwise, but also involve complex sustainability challenges and lead to fundamentally different feedbacks between humans and the environment. This dissertation empirically investigates the sustainability of biophysical human-nature connections and disconnections from a social-ecological systems perspective. The results provide new insights and concrete knowledge about biophysical human-nature disconnections and its sustainability implications, including pervasive issues of injustice. Through international trade and reliance on non-renewables, particularly higher-income regions appropriate an unproportional large share of global resources. Moreover, by enabling seemingly unconstrained consumption of resources and simultaneous conservation of regional ecosystems, increasing regional disconnectedness stimulates the misconception of decoupling. Whereas, in fact, the biophysically most disconnected regions exhibit the highest resource footprints and are, therefore, responsible for the largest environmental damages. The increasing biophysical disconnect between humans and nature effectively works to circumvent limitations and self-constraining feedbacks of natural cycles. The circumvention of environmental constraints is a crucial feature of niche construction. Human niche construction refers to the process of modifying natural environments to make them more useful for society. To ease integration of the chapters in this thesis, the framework paper uses human niche construction theory to understand the mechanisms and drivers behind increasing biophysical disconnections. The theory is employed to explain causal relationships and unsustainable trajectories from a holistic perspective. Moreover, as a process-oriented approach, it allows connecting the empirically assessed states of disconnectedness with insights about interventions and change for sustainability. For a sustainability transformation already entered paths of disconnectedness must be reversed to enable a genuine reconnection of human activities to the biosphere and its natural cycles. This thesis highlights the unsustainability of disconnectedness and opens up debate about how knowledge around sustainable human niche construction can be leveraged for a reconnection of humans to nature.
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.
Vocational Integration of Refugees - Chances and Challenges of Refugee (Social) Entrepreneurship
(2019)
In recent years, especially since 2015, Germany and other European countries have accepted high numbers of refugees. The social and vocational integration of these refugees and of those yet to come represents a challenge. (Social) entrepreneurship is one means to achieve this goal, to fully tap into the potential of refugees and to give them a chance to make a living in host countries. This dissertation examines the potential of vocational integration of refugees through (social) entrepreneurial activities. It includes a detailed literature review and suggests possible direction in the emerging field of refugee (social) entrepreneurship. This dissertation shows that to foster refugee (social) entrepreneurship, the identification and evaluation of specific and potential needs for support is essential. Incubators in particular have a high potential for supporting refugee entrepreneurs, in part it is possible for them to address some of the challenges faced by this target group, which differ from those of locals or migrant entrepreneurs. More specifically, this dissertation aims to answer two research questions: (1) What are relevant (social) entrepreneurial concepts that can contribute to the vocational integration of refugees? (2) What are the distinct contributions of and challenges faced by refugees when it comes to their vocational integration through (social) entrepreneurial activities? Analyzing select practical cases, this dissertation has several important implications for researchers who seek to bridge the gap between academia and society in the context of refugee entrepreneurship and refugee social entrepreneurship research. The findings presented here are also relevant for practitioners, for example those working at business incubators, who aim to facilitate the vocational and social integration of refugees in general and refugees with entrepreneurial aspirations in particular.