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Germany’s relatively stable party system faces a new left-authoritarian challenger: Sahra Wagenknecht’s Bündnis Sahra Wagenknecht (BSW) party. First polls indicate that for the BSW, election results above 10% are within reach. While Wagenknecht’s positions in economic and cultural terms have already been discussed, this article elaborates on another highly relevant feature of Wagenknecht, namely her populist communication. Exploring Wagenknecht’s and BSW’s populist appeal helps us to understand why the party is said to also have potential among seemingly different voter groups coming from the far right Alternative for Germany (AfD) and far left Die Linke, which share high levels of populist attitudes. To analyse the role that populist communication plays for Wagenknecht and the BSW, this article combines quantitative and qualitative methods. The quantitative analysis covers all speeches (10,000) and press releases (19,000) published by Die Linke members of Parliament (MPs; 2005–2023). The results show that Wagenknecht is the (former) Die Linke MP with the highest share of populist communication. Furthermore, she was also able to convince a group of populist MPs to join the BSW. The article closes with a qualitative analysis of BSW’s manifesto that reveals how populist framing plays a major role in this document, in which the political and economic elites are accused of working against the interest of “the majority”. Based on this analysis, the classification of the BSW as a populist party seems to be appropriate.
“Ick bin een Berlina”
(2024)
Background: Robots are increasingly used as interaction partners with humans. Social robots are designed to follow expected behavioral norms when engaging with humans and are available with different voices and even accents. Some studies suggest that people prefer robots to speak in the user’s dialect, while others indicate a preference for different dialects.
Methods: Our study examined the impact of the Berlin dialect on perceived trustworthiness and competence of a robot. One hundred and twenty German native speakers (Mage = 32 years, SD = 12 years) watched an online video featuring a NAO robot speaking either in the Berlin dialect or standard German and assessed its trustworthiness and competence.
Results: We found a positive relationship between participants’ self-reported Berlin dialect proficiency and trustworthiness in the dialect-speaking robot. Only when controlled for demographic factors, there was a positive association between participants’ dialect proficiency, dialect performance and their assessment of robot’s competence for the standard German-speaking robot. Participants’ age, gender, length of residency in Berlin, and device used to respond also influenced assessments. Finally, the robot’s competence positively predicted its trustworthiness.
Discussion: Our results inform the design of social robots and emphasize the importance of device control in online experiments.
Systematic review and meta-analysis of ex-post evaluations on the effectiveness of carbon pricing
(2024)
Today, more than 70 carbon pricing schemes have been implemented around the globe, but their contributions to emissions reductions remains a subject of heated debate in science and policy. Here we assess the effectiveness of carbon pricing in reducing emissions using a rigorous, machine-learning assisted systematic review and meta-analysis. Based on 483 effect sizes extracted from 80 causal ex-post evaluations across 21 carbon pricing schemes, we find that introducing a carbon price has yielded immediate and substantial emission reductions for at least 17 of these policies, despite the low level of prices in most instances. Statistically significant emissions reductions range between –5% to –21% across the schemes (–4% to –15% after correcting for publication bias). Our study highlights critical evidence gaps with regard to dozens of unevaluated carbon pricing schemes and the price elasticity of emissions reductions. More rigorous synthesis of carbon pricing and other climate policies is required across a range of outcomes to advance our understanding of “what works” and accelerate learning on climate solutions in science and policy.
Knowledge about causal structures is crucial for decision support in various domains. For example, in discrete manufacturing, identifying the root causes of failures and quality deviations that interrupt the highly automated production process requires causal structural knowledge. However, in practice, root cause analysis is usually built upon individual expert knowledge about associative relationships. But, "correlation does not imply causation", and misinterpreting associations often leads to incorrect conclusions. Recent developments in methods for causal discovery from observational data have opened the opportunity for a data-driven examination. Despite its potential for data-driven decision support, omnipresent challenges impede causal discovery in real-world scenarios. In this thesis, we make a threefold contribution to improving causal discovery in practice.
(1) The growing interest in causal discovery has led to a broad spectrum of methods with specific assumptions on the data and various implementations. Hence, application in practice requires careful consideration of existing methods, which becomes laborious when dealing with various parameters, assumptions, and implementations in different programming languages. Additionally, evaluation is challenging due to the lack of ground truth in practice and limited benchmark data that reflect real-world data characteristics.
To address these issues, we present a platform-independent modular pipeline for causal discovery and a ground truth framework for synthetic data generation that provides comprehensive evaluation opportunities, e.g., to examine the accuracy of causal discovery methods in case of inappropriate assumptions.
(2) Applying constraint-based methods for causal discovery requires selecting a conditional independence (CI) test, which is particularly challenging in mixed discrete-continuous data omnipresent in many real-world scenarios. In this context, inappropriate assumptions on the data or the commonly applied discretization of continuous variables reduce the accuracy of CI decisions, leading to incorrect causal structures.
Therefore, we contribute a non-parametric CI test leveraging k-nearest neighbors methods and prove its statistical validity and power in mixed discrete-continuous data, as well as the asymptotic consistency when used in constraint-based causal discovery. An extensive evaluation of synthetic and real-world data shows that the proposed CI test outperforms state-of-the-art approaches in the accuracy of CI testing and causal discovery, particularly in settings with low sample sizes.
(3) To show the applicability and opportunities of causal discovery in practice, we examine our contributions in real-world discrete manufacturing use cases. For example, we showcase how causal structural knowledge helps to understand unforeseen production downtimes or adds decision support in case of failures and quality deviations in automotive body shop assembly lines.
In Time and the Other Johannes Fabian analysed how modern conceptions of time were “not only secularized and naturalized but also thoroughly spatialized.” According to Fabian, this was particularly visible in modern anthropology which “promoted a scheme in terms of which not only past cultures but all living societies were irrevocably placed on a temporal slope, a stream of Time – some upstream, others downstream.”3 Anthropologists attributed otherness to a distant past which was traditionally associated with cultural retardation, i.e. a lower degree of development, progress, and civilization. Cultural difference was expressed in terms of temporal distance while temporal distance was attributed to spatial remoteness. The result was a phenomenon that Fabian coined “the denial of coevalness” which pointed towards “a persistent and systematic tendency to place the referent(s) of anthropology in a Time other than the present of the producer of anthropological discourse.
Does working in a gender-atypical occupation reduce individuals’ likelihood of finding a different-sex romantic partner, and do such occupational partnership penalties contribute to occupational gender segregation? To answer this question, we theorized partnership penalties for working in gender-atypical occupations by drawing on insights from evolutionary psychology, social constructivism, and rational choice theory and exploited the stability of occupational pathways in Germany. In Study 1, we analyzed observational data from a national probability sample (N= 1,634,944) to assess whether individuals in gender-atypical occupations were less likely to be partnered than individuals who worked in gender typical occupations. To assess whether the observed partnership gaps found in Study 1 were causally related to the gender typicality of men’s and women’s occupations, we conducted a field experiment on a dating app (N = 6,778). Because the findings from Study 2 suggested that young women and men indeed experienced penalties for working in a gender-atypical occupation (at least when they were not highly attractive), we employed a choice-experimental design in Study 3 (N = 1,250) to assess whether women and men were aware of occupational partnership penalties and showed that anticipating occupational partnership penalties may keep young and highly educated women from working in gender-atypical occupations. Our main conclusion therefore is that that observed penalties and their anticipation seem to be driven by unconscious rather than conscious processes.
We analyze how conventional emissions trading schemes (ETS) can be modified by introducing “clean-up certificates” to allow for a phase of net-negative emissions. Clean-up certificates bundle the permission to emit CO2 with the obligation for its removal. We show that demand for such certificates is determined by cost-saving technological progress, the discount rate and the length of the compliance period. Introducing extra clean-up certificates into an existing ETS reduces near-term carbon prices and mitigation efforts. In contrast, substituting ETS allowances with clean-up certificates reduces cumulative emissions without depressing carbon prices or mitigation in the near term. We calibrate our model to the EU ETS and identify reforms where simultaneously (i) ambition levels rise, (ii) climate damages fall, (iii) revenues from carbon prices rise and (iv) carbon prices and aggregate mitigation cost fall. For reducing climate damages, roughly half of the issued clean-up certificates should replace conventional ETS allowances. In the context of the EU ETS, a European Carbon Central Bank could manage the implementation of cleanup certificates and could serve as an enforcement mechanism.
This study on the Messianic Jewish movement and its relationship to the Torah explores the various aspects of the relationship to the Torah on the basis of 10 interviews with selected Yeshua-believing Jews in leadership positions. The selection of interviewees results in a range of different positions typical of the movement as a whole, which overlap in many respects but are often fundamentally different and sometimes contradictory. Particular attention is paid to the theologically based, divergent and contradictory positions in an attempt to make these understandable.
After a brief introduction to the Messianic Jewish movement, aspects of the Messianic Jewish dual identity are examined and their relevance for the relationship to the Torah is demonstrated. This is followed by an overview of the forums in which Yeshua-believing Jews discuss their relationship to the Torah. The extensive bibliography at the end of the work provides an insight into a lively discussion process within the movement that is still far from complete. A briefly annotated differentiation of terms serves as an overview of the most important meanings of Torah used in the Messianic Jewish movement. Following this preliminary work, the field study is presented. A description of the research field and methodological reflections precede the interviews. In the interviews, the associations with the term Torah are first recorded and the conceptual meaning and use clarified. This already reveals some serious differences. The theological positions and understandings of Torah are presented with the biographical context and main field of influence, and the most important formative influences are named. The points on which they all agree are noted first, as they serve as a common basis. All study the written Torah and consider it, as well as the rest of the Tanakh and the writings of the New Testament in their present form, to be divinely inspired and authoritative. All have found a positive approach to the Torah according to their own definition of the term. For all of them, the written Torah and the Tanakh point to Yeshua. All agree that Yeshua did not abrogate the Torah, but fulfilled it. And all feel a responsibility as a Jew to the Torah in some way. With regard to keeping commandments, all say that no one can earn their way to heaven by doing so. G-d's faithfulness to His promises to Israel is affirmed by all, but whether the new covenant in Yeshua superseded the old covenant of Mt. Sinai, or whether it is simply added to the already existing covenant of Sinai, whether ritual commandments are to continue to be kept after Yeshua's death and resurrection and the destruction of the Temple, whether the commandments aiming at separation from the nations should continue to be kept, whether and under what conditions rabbinic halacha should be followed and what individuals do and teach in their families and communities - all this is discussed interview by interview. It becomes clear how different ways of reading and weighting key scriptures produce different positions. Just as the diversity of positions in relation to the Torah already suggests, the interview partners are divided on the question of a Messianic Jewish Halacha. But here too, the term halacha is interpreted differently by the representatives. At the end of the field study, the attempts to produce Messianic Jewish Halacha and the problems and points of criticism expressed by other interviewees are explained. The work concludes with a theological framework able to contain all the different positions and relationships to the Torah and some starting points for a possible Messianic Jewish hermeneutic theology of the Torah.
The dynamic landscape of digital transformation entails an impact on industrial-age manufacturing companies that goes beyond product offerings, changing operational paradigms, and requiring an organization-wide metamorphosis. An initiative to address the given challenges is the creation of Digital Innovation Units (DIUs) – departments or distinct legal entities that use new structures and practices to develop digital products, services, and business models and support or drive incumbents’ digital transformation. With more than 300 units in German-speaking countries alone and an increasing number of scientific publications, DIUs have become a widespread phenomenon in both research and practice.
This dissertation examines the evolution process of DIUs in the manufacturing
industry during their first three years of operation, through an extensive longitudinal single-case study and several cross-case syntheses of seven DIUs. Building on the lenses of organizational change and development, time, and socio-technical systems, this research provides insights into the fundamentals, temporal dynamics, socio-technical interactions, and relational dynamics of a DIU’s evolution process. Thus, the dissertation promotes a dynamic understanding of DIUs and adds a two-dimensional perspective to the often one-dimensional view of these units and their interactions with the main organization throughout the startup and growth phases of a DIU.
Furthermore, the dissertation constructs a phase model that depicts the early stages of DIU evolution based on these findings and by incorporating literature from information systems research. As a result, it illustrates the progressive intensification of collaboration between the DIU and the main organization. After being implemented, the DIU sparks initial collaboration and instigates change within (parts of) the main organization. Over time, it adapts to the corporate environment to some extent, responding to changing circumstances in order to contribute to long-term transformation. Temporally, the DIU drives the early phases of cooperation and adaptation in particular, while the main organization triggers the first major evolutionary step and realignment of the DIU.
Overall, the thesis identifies DIUs as malleable organizational structures that are crucial for digital transformation. Moreover, it provides guidance for practitioners on the process of building a new DIU from scratch or optimizing an existing one.
Governments engage in corporatization by creating corporate entities or reorganizing existing ones. These corporatization activities reflect an interplay between political agency and environmental pressures, including (changing) notions of state-market relations. This paper discusses two ideal-typed organizational models of corporatization: the state as a marketizer and the marketization of the state. Whereas the first emphasizes the role of political design and agency in corporatization, the second emphasizes the role of (actors in) the environment for corporatization. Both models are assessed across five corporatization episodes in Norway and Sweden, where we also demonstrate the interplay between political agency and environmental pressure.
We examine how the gender of business owners is related to the wages paid to female relative to male employees working in their firms. Using Finnish register data and employing firm fixed effects, we find that the gender pay gap is—starting from a gender pay gap of 11 to 12%—two to three percentage points lower for hourly wages in female-owned firms than in male-owned firms. Results are robust to how the wage is measured, as well as to various further robustness checks. More importantly, we find substantial differences between industries. While, for instance, in the manufacturing sector, the gender of the owner plays no role in the gender pay gap, in several service sector industries, like ICT or business services, no or a negligible gender pay gap can be found, but only when firms are led by female business owners. Businesses with male ownership maintain a gender pay gap of around 10% also in the latter industries. With increasing firm size, the influence of the gender of the owner, however, fades. In large firms, it seems that others—firm managers—determine wages and no differences in the pay gap are observed between male- and female-owned firms.
Organizational commitments to equality change how people view women’s and men’s professional success
(2024)
To address women’s underrepresentation in high-status positions, many organizations have committed to gender equality. But is women’s professional success viewed less positively when organizations commit to women’s advancement? Do equality commitments have positive effects on evaluations of successful men? We fielded a survey experiment with a national probability sample in Germany (N = 3229) that varied employees’ gender and their organization’s commitment to equality. Respondents read about a recently promoted employee and rated how decisive of a role they thought intelligence and effort played in getting the employee promoted from 1 “Not at all decisive” to 7 “Very decisive” and the fairness of the promotion from 1 “Very unfair” to 7 “Very fair.” When organizations committed to women’s advancement rather than uniform performance standards, people believed intelligence and effort were less decisive in women’s promotions, but that intelligence was more decisive in men’s promotions. People viewed women’s promotions as least fair and men’s as most fair in organizations committed to women’s advancement. However, women’s promotions were still viewed more positively than men’s in all conditions and on all outcomes, suggesting people believed that organizations had double standards for success that required women to be smarter and work harder to be promoted, especially in organizations that did not make equality commitments.
Money matters!
(2024)
This paper examines the context dependency of attitudes toward maternal employment. We test three sets of factors that may affect these attitudes—economic benefits, normative obligations, and child-related consequences—by analyzing data from a unique survey experimental design implemented in a large-scale household panel survey in Germany (17,388 observations from 3,494 respondents). Our results show that the economic benefits associated with maternal employment are the most important predictor of attitudes supporting maternal employment. Moreover, we find that attitudes toward maternal employment vary by individual, household, and contextual characteristics (in particular, childcare quality). We interpret this variation as an indication that negative attitudes toward maternal employment do not necessarily reflect gender essentialism; rather, gender role attitudes are contingent upon the frames individuals have in mind.
Social institutions
(2024)
Social institutions are a system of behavioral and relationship patterns that are densely interwoven and enduring and function across an entire society. They order and structure the behavior of individuals in core areas of society and thus have a strong impact on the quality of life of individuals. Institutions regulate the following: (a) family and relationship networks carry out social reproduction and socialization; (b) institutions in the realm of education and training ensure the transmission and cultivation of knowledge, abilities, and specialized skills; (c) institutions in the labor market and economy provide for the production and distribution of goods and services; (d) institutions in the realm of law, governance, and politics provide for the maintenance of the social order; (e) while cultural, media, and religious institutions further the development of contexts of meaning, value orientations, and symbolic codes.
Examining the dissemination of evidence on social media, we analyzed the discourse around eight visible scientists in the context of COVID-19. Using manual (N = 1,406) and automated coding (N = 42,640) on an account-based tracked Twitter/X dataset capturing scientists’ activities and eliciting reactions over six 2-week periods, we found that visible scientists’ tweets included more scientific evidence. However, public reactions contained more anecdotal evidence. Findings indicate that evidence can be a message characteristic leading to greater tweet dissemination. Implications for scientists, including explicitly incorporating scientific evidence in their communication and examining evidence in science communication research, are discussed.
It has been highlighted many times how difficult it is to draw a boundary between gift and bribe, and how the same transfer can be interpreted in different ways according to the position of the observer and the narrative frame into which it is inserted. This also applied of course to Ancient Rome; in both the Republic and Principate lawgivers tried to define the limits of acceptable transfers and thus also to identify what we might call ‘corruption’. Yet, such definitions remained to a large extent blurred, and what was constructed was mostly a ‘code of conduct’, allowing Roman politicians to perform their own ‘honesty’ in public duty – while being aware at all times that their involvement in different kinds of transfer might be used by their opponents against them and presented as a case of ‘corrupt’ behaviour.
Have you already swiped or liked this morning? Have you taken part in a video conference at work, used or programmed a database? Have you paid with your smartphone on the way home, listened to a podcast, or extended the lending of books you borrowed from the library? And in the evening, have you filled out your tax return application on ELSTER.de on your tablet, shopped online, or paid invoices before you were tempted to watch a series on a streaming platform?
Our lives are entirely digitalized.
These changes make many things faster, easier, and more efficient. But keeping pace with these changes demands a lot from us, and not everyone succeeds. There are people who prefer to go to the bank to make a transfer, leave the programming to the experts, send their tax return by mail, and only use their smartphone to make phone calls. They don’t want to keep pace, or maybe they can’t. They haven’t learned these things. Others, younger people, grow up as “digital natives” surrounded by digital devices, tools, and processes. But does that mean they really know how to use them? Or do they also need digital education?
But what does successful digital education actually look like? Does it teach us how to use a tablet, how to google properly, and how to write Excel spreadsheets? Perhaps it’s about more than that. It’s about understanding the comprehensive change that has been taking hold of our world since it was broken down into digital ones and zeros and rebuilt virtually. But how do we learn to live in a world of digitality – with all that it entails, and to our benefit?
For the new issue of “Portal Wissen”, we looked around at the university and interviewed researchers about the role that the connection between digitalization and learning plays in the research of various disciplines. We spoke to Katharina Scheiter, Professor of Digital Education, about the future of German schools and had several experts show us examples of how digital tools can improve learning in schools. We also talked to computer science and agricultural researchers about how even experienced farmers can still learn a lot about their land and their work thanks to digital tools. We spoke to educational researchers who are using big data to analyze how boys and girls learn and what the possible causes for differences are. Education and political scientist Nina Kolleck, on the other hand, looks at education against the backdrop of globalization and relies on the analysis of large amounts of social media data.
Of course, we don’t lose sight of the diversity of research at the University of Potsdam. We learn, for example, what alternatives to antibiotics could soon be available. This magazine also looks at stress and how it makes us ill as well as the research into sustainable ore extraction.
A new feature of our magazine is a whole series of shorter articles that invite you to browse and read: from research news and photographic insights into laboratories to simple explanations of complex phenomena and outlooks into the wider world of research to a small scientific utopia and a personal thanks to research. All this in the name of education, of course. Enjoy your read!
Enhancing economic efficiency in modular production systems through deep reinforcement learning
(2024)
In times of increasingly complex production processes and volatile customer demands, the production adaptability is crucial for a company's profitability and competitiveness. The ability to cope with rapidly changing customer requirements and unexpected internal and external events guarantees robust and efficient production processes, requiring a dedicated control concept at the shop floor level. Yet in today's practice, conventional control approaches remain in use, which may not keep up with the dynamic behaviour due to their scenario-specific and rigid properties. To address this challenge, deep learning methods were increasingly deployed due to their optimization and scalability properties. However, these approaches were often tested in specific operational applications and focused on technical performance indicators such as order tardiness or total throughput. In this paper, we propose a deep reinforcement learning based production control to optimize combined techno-financial performance measures. Based on pre-defined manufacturing modules that are supplied and operated by multiple agents, positive effects were observed in terms of increased revenue and reduced penalties due to lower throughput times and fewer delayed products. The combined modular and multi-staged approach as well as the distributed decision-making further leverage scalability and transferability to other scenarios.
The increasing number of known exoplanets raises questions about their demographics and the mechanisms that shape planets into how we observe them today. Young planets in close-in orbits are exposed to harsh environments due to the host star being magnetically highly active, which results in high X-ray and extreme UV fluxes impinging on the planet. Prolonged exposure to this intense photoionizing radiation can cause planetary atmospheres to heat up, expand and escape into space via a hydrodynamic escape process known as photoevaporation. For super-Earth and sub-Neptune-type planets, this can even lead to the complete erosion of their primordial gaseous atmospheres. A factor of interest for this particular mass-loss process is the activity evolution of the host star. Stellar rotation, which drives the dynamo and with it the magnetic activity of a star, changes significantly over the stellar lifetime. This strongly affects the amount of high-energy radiation received by a planet as stars age. At a young age, planets still host warm and extended envelopes, making them particularly susceptible to atmospheric evaporation. Especially in the first gigayear, when X-ray and UV levels can be 100 - 10,000 times higher than for the present-day sun, the characteristics of the host star and the detailed evolution of its high-energy emission are of importance.
In this thesis, I study the impact of stellar activity evolution on the high-energy-induced atmospheric mass loss of young exoplanets. The PLATYPOS code was developed as part of this thesis to calculate photoevaporative mass-loss rates over time. The code, which couples parameterized planetary mass-radius relations with an analytical hydrodynamic escape model, was used, together with Chandra and eROSITA X-ray observations, to investigate the future mass loss of the two young multiplanet systems V1298 Tau and K2-198. Further, in a numerical ensemble study, the effect of a realistic spread of activity tracks on the small-planet radius gap was investigated for the first time. The works in this thesis show that for individual systems, in particular if planetary masses are unconstrained, the difference between a young host star following a low-activity track vs. a high-activity one can have major implications: the exact shape of the activity evolution can determine whether a planet can hold on to some of its atmosphere, or completely loses its envelope, leaving only the bare rocky core behind. For an ensemble of simulated planets, an observationally-motivated distribution of activity tracks does not substantially change the final radius distribution at ages of several gigayears. My simulations indicate that the overall shape and slope of the resulting small-planet radius gap is not significantly affected by the spread in stellar activity tracks. However, it can account for a certain scattering or fuzziness observed in and around the radius gap of the observed exoplanet population.