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The choice to continue working until or even beyond retirement is a function of the interplay of factors on micro, meso, and macro levels. Research within this area has grown significantly over the last years. I contribute to this line of research with the studies conducted within the scope of this cumulative habilitation thesis. More specifically, the aim of the research presented here is to add to the literature on later life work with the investigation of individual (micro level) as well as job and organizational (meso level) factors that have the potential to contribute to prolonged working lives. I was guided by the general research interest on how individual, job, and organizational factors contribute to later life work, and more specifically to retirement timing and work-related activities beyond normal retirement age. My research was directed by the following research questions: (1) What is the work activity potential of older people in Germany and what characterizes different types of later life work potential? (2) Which role do individual psychological factors such as personality, values, and beliefs play in the context of later life work? (3) How do specific job characteristics interact or align with individual psychological factors with regard to later life work? (4) What characterizes a holistic organizational approach to later life work that helps the alignment of the work environment to older workers’ (individual) needs and abilities? Following an introduction, I give an overview on the theoretical framework of my research in Chapter 2 (“Theoretical Background”). I describe the conceptualization of later life work before I go into multilevel antecedents of later life work and present key theoretical approaches to a person-environment fit perspective of later life work. In the following four chapters, I present ten studies corresponding to the ten scientific publications that constitute the basis of the cumulative habilitation thesis. In Chapter 3 (“Later Life Work: Work Activity Potential”) I present research on the extent as well as different types of later life work potential in Germany to describe the context for most of my research. With the two studies presented here (Büsch, Zohr, Brusch, Deller, Schermuly, Stamov-Roßnagel, & Wöhrmann, 2015; Mergenthaler, Wöhrmann, & Staudinger; 2015), I also intend to provide answers to the research question on the later life work potential in Germany and the characteristics of different later life work potential constellations. In Chapter 4 (“Later Life Work: Individual Psychological Factors”) the role of stable as well as malleable individual psychological factors for later life work is explored in two studies (Fasbender, Wöhrmann, Wang, & Klehe, 2019; Wöhrmann, Fasbender, & Deller, 2016). Thus, with the studies presented in this chapter, I contribute to the research question on the role of individual psychological factors in the context of later life work. In Chapter 5 (“Later Life Work: Job Characteristics Corresponding to Older Workers’ Needs and Abilities”) I present three studies exploring the interplay of individual factors and job characteristics for later life work to address the research question on the interaction or alignment of specific job characteristics with individual psychological factors with regard to later life work (Pundt, Wöhrmann, Deller, & Shultz, 2015; Wöhrmann, Brauner, & Michel, 2020; Wöhrmann, Fasbender, & Deller; 2017). Chapter 6 (“Later Life Work: A Holistic Organizational Approach”) reports the development of the Later Life Workplace Index (LLWI) as a multidimensional tool to holistically assess organizational practices and working conditions targeted at the promotion of later life work through the maintenance and enhancement of older employees’ health, work ability, and motivation (Wilckens, Wöhrmann, Adams, Deller, & Finkelstein, 2020; Wilckens, Wöhrmann, Deller, & Wang, 2020; Wöhrmann, Pundt, & Deller, 2018. With the LLWI, I intend to provide an answer to the research question on the characteristics of a holistic organizational approach to later life work that helps the alignment of the work environment to older workers’ (individual) needs and abilities. Finally, in Chapter 7 (“General Discussion”) I discuss the contributions, implications, and limitations of my research presented here.

Consisting of three articles and a framework manuscript, this cumulative dissertation deals with sustainable compensation of chief executive officer (CEO) with a focus on climate-related aspects. Against the backdrop of the European action for sustainability and the EU Green Deal, the dissertation pays special attention to the consideration of climate-related aspects of corporate performance in CEO compensation. In this context, sustainable compensation is characterized by the consideration of long-term interests and sustainability of the company as well as by the inclusion of financial and non-financial aspects of environmental, social and governance performance (ESG) in compensation agreements. While this novel instrument of corporate governance aims to incentivize the implementation of sustainability-oriented corporate strategy, it is particularly important to unfold this incentive effect at the individual CEO level in view of their managerial discretion. The framework manuscript discusses the research objectives, the regulatory and theoretical background, the results of the dissertation and their implications in the context of regulation, research, and business practice. The essence of the dissertation are the three articles. The first article, "Determinants and effects of sustainable CEO compensation: a structured literature review of empirical evidence," examines the current state of empirical research based on 37 articles that were published between 1992 and 2018. Based on a multidimensional research framework, the structured literature review compiles past research findings, identifies contentual and methodological foci in the research area, and derives questions for future research. The second article, "Mapping the determinants of carbon-related CEO compensation: a multidimensional approach," addresses the topic from a conceptual perspective. Taking the existing work as a starting point, a conceptual framework is derived, which organizes the determinants of carbon-related CEO compensation at societal, organizational, group and individual levels of analysis. On this basis, eight propositions are presented that seek to distinguish between the determinants which support and challenge the implementation of carbon-related CEO compensation. The third article, "Climate change policies and carbon-related CEO compensation systems: an exploratory study of European companies," focuses on the use of CO2-oriented performance indicators in CEO compensation. The empirical-qualitative study analyzes corporate disclosure of the 65 largest companies in the EU for the years 2018 and 2019. The study addresses the use of CO2-oriented performance indicators in corporate strategy and CEO compensation. It also examines which compensation components are determined with the help of CO2-oriented performance indicators, which type of performance indicators are used, and whether CO2-intensive and less CO2-intensive companies differ in this regard.

Understanding that entrepreneurship can be better modeled from a systemic point of view is a primordial aspect that determines the important role of universities in entrepreneurial ecosystems. What makes the ecosystem approach a valuable tool for understanding social systems is that, from a holistic perspective, their behavior seems to have emerging characteristics. The impact of this “research object” can only be revealed through interrelated causal chains similar to the behavior of natural ecosystems (Mars et al., 2012). Therefore, the entrepreneurial ecosystem concept provides a unique perspective that complements previous studies on networked economic activity with a clear focus on the systemic elements that support entrepreneurship, and an emphasis on policy that promote the entrepreneurial process. This dissertation presents a dual scientific account of the entrepreneurship phenomenon in universities. The work is divided into two equal parts, each of which is composed of two research papers. The narrative of the first half takes on a macro perspective view, consisting of one theoretical and one empirically-based conceptual case study. This part conceptually depicts a systematic approach to entrepreneurialism in higher education, namely an ecosystems perspective. The second half concentrates on the meso- and micro levels of study from the university’s point of view, comprising of a case study as historical account for the emergence of the entrepreneurial university, and of a metasynthesis of empirical case studies in entrepreneurial universities, which serves as the basis for the development of entrepreneurial university archetypes. This doctoral work contributes to an in-depth understanding of Entrepreneurship in universities regarding its systemic qualities and archetypal characteristics of entrepreneurial universities. It argues for an ecosystem’s perspective on the phenomenon of entrepreneurial activity, highlighting the fundamental role that universities play as the heart of entrepreneurial ecosystems. Furthermore, this research expands on the novel concept of the entrepreneurial university by using extensive case study literature to empirically identify distinct archetypes that better reflect the diverse reality of how universities engage as entrepreneurial actors by way of differentiated entrepreneurial structures, systems, and strategies.

Companies increasingly use social and environmental accounting and reporting (SEAR) to measure, manage, and report their influence on ecological and social issues, i.e., climate change and human rights violations. One reason for the increased use of SEAR is that companies aim to support sustainable aspects in their business decision-making. Nowadays, there are many different tools, frameworks, and standards for SEAR that companies can use. Beyond the content presented in the tool itself, e.g., social and/or ecological information, these tools differ, among others, by the language used and the type of data collected (e.g., qualitative, quantitative, or monetary data). One the one hand, the range of different approaches for SEAR allows industry- and company-specific monitoring and reporting of sustainable issues. On the other hand, this variety as well as the lack of a common reference framework can lead to uncertainty of corporate decision-makers and stakeholders regarding the use and comparability of these approaches. While numerous previous scholars present advantages and opportunities of the use of SEAR for companies and society, there is a rising number of scholars criticizing the way (social and environmental) accounting and reporting is used today and its impact on a company’s environmental orientation and decision-making. Further, there is only limited literature on the question of which approach to use and how to use and introduce the particular approach for supporting sustainable decision-making within companies. This dissertation aims to expand previous literature by clarifying the effects of SEAR on corporate decision-making and its influencing factors. Additionally, antecedents for implementation and use of SEAR in regard to supporting sustainability decision-making are discussed. For this purpose, the given dissertation investigates public sustainability reports by companies with different environmental orientation, conducts two survey-based case studies on the effects of different types of SEAR and one qualitative case study on the antecedents of institutionalizing management accounting change through SEAR. The results lead to seven criteria that practitioners and researchers should recognize for supporting successful SEAR regarding a company’s environmental orientation, the role of employees and leadership as well as the specific SEAR tool itself. Additionally, this dissertation leads to several contributions to the scientific discussion and its influences on corporate environmental orientation and decision-making.

This dissertation presents an analysis of the relations to self and technology that emerge from and in the use of self-tracking technologies. The ethnographical study, combined with the Grounded Theory approach and a media analysis, demonstrates the complex intertwining or duality of control and care towards oneself that emerge or become possible in and through the application of ST technologies. ST devices assist in strengthening one's health and well-being in a playful way, building and maintaining a positive self-feeling, self-image and agency, and discovering unknown abilities and potentials within oneself. The ST technologies used provide orientation through complexity-reducing visualizations, highlighting patterns, and trend progression. They challenge through self-overload, dissatisfaction when not achieving goals, self-deception and distraction, narcissism and even loss of control - internally through compulsion to control as well as externally through loss of data otection and exploitation of private data by third parties, as well as handing over responsibility (in the form of decisions) to technology (algorithms) instead of self-responsibility. These two seemingly opposed yet concurrently existing self-relations reflect the dynamic between today's demands for self-responsibility (in health and performance terms) and the need for self-care and guidance for the many relevant, sometimes daily, decisions. They balance possibly existing tensions and ambiguities between the modes of self-relations that at first glance seem to be opposed and yet ultimately are jointly oriented towards the same goal, namely to master one's life (life maintenance) and to be in balance. The self-relations described in this thesis are supported, reinforced, or enabled by ST technology (and practice). Three different roles that ST technology can take in self-care and self-control were elaborated: technology as a means, a counterpart, and a promise. In relation to technology, another dialectic is visible, which shows the apparent contrast between its conception as a tool and means to achieve something and the approach to technology as an intimate counterpart (partner, nanny, coach) and a promise of salvation. The relationship with technology seems to intensify in and through the ST experience and takes on or is assigned a partner-like role by the users. Finally, the results indicate that the concept of (self-)optimization, contrary to its etymological meaning of a logic of increase, can also be understood differently, namely balancing. In this context, optimization does not necessarily mean the fastest, the highest, the strongest, but something that is achievable and satisfactory for the self - within the framework of the given and the desired. At the same time, the optimization understood as harmonizing and balancing in self-tracking becomes a lifelong task that, in principle, can never be completed because with the addition of new vital areas in life and throughout a lifetime also the individually understood and conceived balance often shifts.

Global environmental changes and the subsequent biodiversity loss has raised concerns over the consequences for the functioning of ecosystems and human well-being. This thesis provides new mechanistic insights into the role of tree diversity in regulating forest productivity and forests’ responses to climate change. The thesis also addresses the overlooked functional role of ecological continuity in mediating ecosystem processes in the context of multiple global environmental changes. The findings of the thesis emphasize the need to retain the functional integrity of forest ecosystem by preserving biodiversity and acknowledging the ecological memory forests.

This cumulative dissertation investigates food policy councils (FPCs) as potential levers for sustainability transformation. The four research papers included here on this recent phenomenon in Germany present new insights regarding the process of FPCs’ emergence (Emergence paper), the legal conditions which affect their establishment (Legal paper), the different roles of FPCs in policy-making processes (Roles paper) and FPCs’ potential to democratise the food system (Food democracy paper). Drawing on and contextualizing the results of the four individual studies, the framework paper uses the leverage points concept originally developed by Meadows (1999) and adopted by Abson et al. (2016) as a lens to discuss FPCs’ potential as levers for sustainability transformation. This conceptual background includes three so-called realms of leverage, which are considered to be of particular importance in transformational, solution-oriented sustainability science: first, the change, stability and learning in institutions (re-structure), second, the interactions between people and nature (re-connect) and third, the ways in which knowledge is produced and used (re-think). Framing the findings of the four research papers in terms of these three realms, the framework paper shows that FPCs could serve as cross realm levers, i.e. as interventions that simultaneously address knowledge production, institutional reform and human-nature interactions.

This dissertation, entitled “How to Embed Sustainability in the Core of Higher Education Institutions: Drivers of, Barriers to, & Patterns behind the Implementation Processes of Sustainability Curricula – Insights from a Quantitative Meta-Study with Data from around the Globe,” addresses the question of how sustainability curricula1 can be implemented and established in higher education institutions2. This research question is based on the assumption that sustainable development requires new ways of thinking and acting in the world. Accordingly, universities – as hubs for knowledge generation, innovation, and education – provide a central leverage point for sustainably developing society at large. Therefore, the institutionalization of sustainability curricula is not only socially demanded, but also stipulated in numerous political statements from the international community (e.g., those of the UN and UNESCO) and operationalized via Sustainable Development Goal No. 4: “Quality Education”. Previous findings on how such implementation can be successful and what factors support or inhibit the process have come primarily through case studies of individual higher education institutions. These studies provide important insights but have been largely descriptive rather than analytical and leave open questions about the generalizability of their findings – for example, the extent to which other universities can be guided by the experiences of the respective higher education institutions. The present dissertation addresses this research gap. Through a meta-study (i.e., an analytical comparison of existing case studies), generalizable findings on the implementation processes of sustainability curricula are explored. In the first step, a case universe was collected in order to provide a database for deeper analyses. In two further analysis steps that built on the case universe from Step 1, certain factors that promote or inhibit the implementation of sustainability curricula (Step 2) and specific implementation patterns (Step 3) were examined. The following paragraphs provide greater details and an overview of the respective findings. In the first step, a database of peer-reviewed English-language case studies from around the globe that report on such processes was created. A total of 230 case studies were identified, 133 of which focus on the implementation processes of sustainability curricula.3 A bibliometric analysis of the 230 case studies revealed that this field of research is growing, although the discourse is primarily dominated by authors from North America, Europe, Oceania, and Asia, with South America and Africa being underrepresented. In addition, a citation analysis demonstrated that some universities incorporate findings from other countries whereas other universities act in isolation. This observation leaves open the question of the extent to which universities learn from one another in order to advance the implementation of sustainability curricula. In the second step of the analysis, the qualitative data of the collected case studies (sample of 133 case studies) were compared using the case survey method, which is a specific type of a meta-1 Sustainability curricula include courses, programs, and certificates from all fields of study that deal in some form with sustainability topics. For a more-detailed discussion of what education for sustainable development (ESD) entails, see Section Error! Reference source not found.. 2 Higher education institutions (HEIs) include universities, universities of applied sciences, and other institutions that offer at least a bachelor’s degree. 3 A detailed explanation of the case sample and subsamples can be found in Section Error! Reference source not found.. analysis. The focus of the comparison lay on the drivers of and barriers to the processes of sustainability curriculum implementation at higher education institutions. Driving- and inhibiting factors have been thoroughly examined theoretically in the discourse on education for sustainable development (ESD), especially those pertaining to higher education institutions. However, no large body of data has yet been created to empirically test these hypotheses. The present meta-study found that the following factors lead to the deep-rooted and comprehensive establishment of sustainability curricula: strong leadership support; the establishment of sustainability curricula in the areas of education, research, campus operations, and outreach activities; formal participation of internal (including students) and external stakeholders; and engagement by sustainability champions (change agents), who are often the first to implement sustainability curricula and can face strong resistance. Other enabling factors include strategic planning, coordination, communication, having a vision, external political influence, the presence of a window of opportunity (e.g., an environmental disaster, a change in presidency), and the availability of interdisciplinary meeting spaces. On the other hand, the strongest cited barriers to the implantation of sustainability curricula were found to be the lack of interdisciplinary meeting spaces, the lack of a vision, the lack of incentives, the lack of resources, an overly full curriculum, and an unsupportive / overly bureaucratic organizational structure. The third step of the analysis also built on data from the 133 case studies and explored whether certain types or patterns of implementation processes occur. Through the analysis, six implementation patterns were identified that share similar driving- and inhibiting factors. The respective interplay between factors leads to various degrees of sustainability curriculum implementation in terms of how deeply rooted and comprehensive this implementation is. As discussed in greater detail below, in descending order of the level of achieved deep-rooted change, these patterns are (1) a collaborative paradigm shift, (2) bottom-up institutional change, (3) top-down institutional change, (4) the presence of many barriers that hinder institutional change, (5) externally driven initiatives, and (6) initiatives that are scattered due to a lack of coordination. Across all patterns, two phases could be identified: First, the impetus to implement ESD may be initiated not only by internal actors, but also by external ones. This initiation can take hold from the “bottom-up” (i.e., by students or faculty), from the “top-down” (i.e., at the presidential level), or in both directions simultaneously. The following key factors appear to be important in driving the initial implementation forward: a culture of open communication between all stakeholders in which feedback and reflection are welcome and even actively solicited, the development of a shared understanding and vision that further create a sense of ownership and long-term success, a high level of collaboration among all stakeholders, and existing initiatives that lead to knowledge sharing and other resources. In this regard, informal collaboration and cooperation can partially compensate for a lack of presidential-level support and/or a formal communication structure. Furthermore, developing a strategy with individual steps and shared responsibility leads to more-successful implementation of ESD at higher education institutions. The presented findings add a complementary empirical perspective to the discourse on the establishment of ESD at higher education institutions. First, the case studies that specifically address the implementation processes of sustainability curricula are reviewed and analyzed here for the first time as part of a research landscape. This research landscape reveals where research on such implementation processes has been or is being conducted. On this basis, both researchers and funders can reflect on the status quo and plan further research- or funding endeavors. Second, this dissertation offers the opportunity to compare a multitude of individual case studies and thus to develop new and generalizable insights into the implementation of sustainability curricula. The empirical analysis uses 133 case studies to identify key factors that promote or inhibit the implementation of sustainability curricula and to add a complementary perspective to the discourse, which has thus far been dominated by theoretical considerations and individual case studies. The analysis thereby offers a new perspective on generalizable influencing factors that appear to be important across different contexts. Thus far, specific patterns of implementation processes have been infrequently studied, and with few datasets. This dissertation analyzes the complex interplay between over 100 variables and provides one of the first research attempts at better understanding the processes that lead to the deep-rooted and comprehensive implementation of sustainability curricula. Internal and external practitioners of higher education institutions can find examples and evidence that can be useful in planning the next steps of their sustainability curriculum implementation. In the future, higher education institutions will play an even greater role in the journey toward sustainable development. This dissertation offers generalizable empirical findings on how universities can succeed in recognizing their own responsibility to that end and in realizing this transformation through the implementation of ESD.

Mental health is an important factor in an individuals’ life - more than 300 million individuals suffered from depression in 2015. Online-based interventions have been developed for the treatment of various mental disorders. These types of interventions have proven their efficacy and can lead to positive outcomes for suffering patients. During these interventions, a large amount of patient-specific data is gathered that can be utilized to increase treatment outcomes by informing decision-making processes of psychotherapists, experts in the field, and patients. The articles included in this dissertation focus on the analysis of such data collected in digital psychological treatments by using machine learning approaches. This dissertation utilizes various machine learning methods such as Bayesian models, regularization techniques, or decision trees to predict different psychological factors, such as mood or self-esteem, dropout of patients, or treatment outcomes and costs. These models are evaluated using a variety of performance metrics, for example, receiver operating characteristics curve, root mean square error, or specialized performance metrics for Bayesian inference. These types of analyses can support decision- making for psychologists and patients, which can, in turn, lead to better recommendations and subsequently to increased outcomes for patients and simultaneously more insight about the interplay between psychological factors. The contribution of this interdisciplinary dissertation is manifold and can be classified at the intersection of Information Systems, health economics, and psychology. The analysis of user journey data has not yet been fully examined in the field of psychological research. A process for this endeavor is developed and a technical implementation is provided for the research community. The application of machine learning in this context is still in its infancy. Thus, another contribution is the exploration and application of machine learning techniques for the revelation of correlations between psychological factors or characteristics and treatment outcomes as well as their prediction. Additionally, economic factors are predicted to develop a process for treatment type recommendations. This approach can be utilized for finding the optimal treatment type for patients on an individual level considering predicted treatment outcomes and costs. By evaluating the predictive accuracy of multiple machine learning techniques based on various performance metrics, the importance of considering heterogeneity among patients’ behavior and affect is highlighted in some articles. Furthermore, the potential of machine learning-based decision support systems in clinical practice has been examined from a psychotherapists’ point of view.

Summary Since the early 2000s, ecosystem services strongly gained significance as a research topic. While the number of papers strongly increased, the concept was further developed which changed the way it was applied. From highlighting the value of ecosystems by viewing them not only from an ecological, but also from an economic perspective in the beginning, it is nowadays, among others, used to map and calculate the monetary value of ecosystem services. Lately, the International Panel on Biodiversity and Ecosystem Services (IPBES) further developed the concept into Nature’s contributions to people (NCP) which puts a stronger emphasis on stakeholders and indigenous knowledge. However, so far none of the conceptual developments managed to integrate the temporal dimension of ecosystem services into this concept, although this should be the basis for a sustainable long-term management of ecosystems and their services. Therefore, I present three articles in this thesis that deal with temporal aspects of ecosystem services. In two of them I also present a proposal for a framework for the classification of ecosystem services based on their temporal dynamics. In this dissertation I differentiate between two types of temporal aspects, both of which have in common that change takes place over a certain period of time. The concepts of transformation, transition and regime shift are used to describe changes in social or ecological systems as a whole, for example the transformation towards a more sustainable society. The temporal dynamics that I present, on the other hand, relate to the temporal changes in ecosystem services themselves. The first article focuses on how the literature on ecosystem services incorporates social and ecological change, illustrated by the concepts of transformation, transition, and regime shift. The second and third articles deal with the temporal dynamics of ecosystem services. While the second article presents a preliminary framework for categorizing the temporal dynamics of ecosystem services, the third article uses this framework to test how the temporal dynamics of ecosystem services are represented in the literature. Based on the insights from the three articles, I conclude that most of the studies on ecosystem services only focus on one point in time. One reason for this is that most studies are conducted over a maximum of a four-year time span which does not allow to monitor dynamics over longer time spans. In most articles that do account for temporal aspects, the focus is strongly on the side of ecological supply of ecosystem services rather than on the demand-side which leads to the exclusion of stakeholder perceptions and therefore, makes it impossible to connect ecosystem service demand and supply over time. Moreover, the concept of change that is used most often in the literature is that of regime shifts which comes from a purely ecological background and focuses mostly on changes that happened in the past. This neglects the possibility of change towards a positive outcome in the future. In general, there is a strong disciplinary divide in the concepts and terminology used. This leads to a lack of exchange between different scientific disciplines and non-academic stakeholders. Approaches that are needed to solve problems of ecosystem service management are therefore impeded. To enable future research to better account for temporal aspects and connect supply and demand sides of ecosystem services with each other, I give four recommendations for future research. These are (I) take temporal dynamics into account by conducting long-term research, (II) ensure conceptual clarity, (III) create a solution-oriented agenda and (IV) take the demand side into account by involving stakeholders’ perceptions over time. By following these recommendations, future research could help to support the sustainable management of ecosystem services as dynamics will be better known and targeted measures can be implemented.