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„Wetten, dass ich ein besserer Mensch bin?“ – Moralisierung als Problem für den demokratischen Diskurs?
Full text linkTowards Behavioural Model Parameterization: Integrated Evaluation of Hydrological Modeling and Parameterization Schemes for Improved Water Balance Simulations, Considering Pedo-transfer Functions and Spatial Patterns of Runoff Generation Processes
Full text linkDie vorliegende Dissertation beschäftigt sich mit der Anwendung und Weiterentwicklung physikalisch basierter, räumlich verteilter Niederschlag-Abfluss-Modelle. Diese Modelle simulieren die hydrologischen Prozesse detailliert und berücksichtigen dabei die räumli-chen und zeitlichen Dynamiken hydrologischer Variablen. Die konventionelle Modellbe-wertung basiert überwiegend auf Abflussdaten, was zu einer eingeschränkten Darstellung der Einzugsgebietsdynamik führen kann. Die Arbeit unterstreicht daher die Notwendigkeit, eine umfassendere Bewertung der Modelle zu implementieren, die sowohl interne hydrolo-gische Prozesse als auch andere Wasserbilanzkomponenten einbezieht.
Ein wesentliches Element der Dissertation ist die kritische Analyse der Auswahl und Anwendung von Pedo-Transfer-Funktionen (PTFs). Diese Funktionen sind entscheidend für die Parametrisierung von Bodenwasserretentions- und Hydraulikeigenschaften. Es wird gezeigt, dass die Wahl der PTFs erheblichen Einfluss auf die Modellsensitivität in Bezug auf die räumliche Verteilung dieser Eigenschaften und auf die Simulation der hydrologi-schen Prozesse hat.
Durch den Einsatz verschiedener PTFs in einem kalibrierten und validierten Modell konnte die Variabilität der Simulationsergebnisse bezüglich der Bodenfeuchte, der Eva-potranspiration und der Abflusskomponenten deutlich dargestellt werden.
1. Manuskript: Evaluation des hydrologischen Modellverhaltens unter Nut-zung eines Multi-Kriterien-Bewertungsschemas, das sowohl quantitative als auch qualitative Daten integriert. Hierdurch konnten optimale Parameterkonfigurationen für Boden und Vegetation identifiziert werden, die zu konsistenten Simulationsresul-taten für Transpiration und Bodenwasser im Vergleich zu gemessenen Daten führten.
2. Manuskript: Es behandelt die Sensitivität des Wasserhaushaltsmodells be-züglich der Auswahl von PTFs in einem kleinen Einzugsgebiet in Bayern. Durch Va-riation der PTFs in einem kalibrierten Modell wurden deren Auswirkungen auf die räumliche Verteilung der Bodenhydraulikeigenschaften sowie auf die Wasserbilanz und die räumlich-zeitliche Variation der Abflusskomponenten aufgezeigt
3. Manuskript: Fokussiert auf die Verbesserung der räumlichen Darstellung dominanter Abflussprozesse in einem mesoskaligen Einzugsgebiet in Südwest-deutschland. Die Anwendung einer räumlichen Leistungsmetrik (SPAEF) ermöglich-te den Vergleich der simulierten Muster mit den Mustern, die aus digitalen Boden-karten abgeleitet wurden, und zeigte eine hohe Variabilität in Bezug auf Landnut-zung, Topographie und angewandte Niederschlagsraten.
Die Ergebnisse der Dissertation tragen zur Lösung der in der hydrologischen Forschung identifizierten Probleme bei, insbesondere in Bezug auf die räumliche Variabilität und die Methoden der Modellierung. Sie bieten neue Perspektiven für die Kalibrierungsverfahren, die darauf abzielen, plausible Dynamiken (sowohl räumlich als auch zeitlich) der hydrolo-gischen Prozesse innerhalb des Wassereinzugsgebiets zu reproduzieren. Die weiterführen-den Untersuchungen, die in dieser Arbeit gefördert werden, sind von großer Bedeutung für die Entwicklung umfassender Modellkalibrierungsstrategien, die multiple Datenquellen simultan berücksichtigen und somit zu nachhaltigeren Wasserwirtschaftsentscheidungen beitragen können.Physically-based distributed rainfall-runoff models as the standard analysis tools for hydro-logical processes have been used to simulate the water system in detail, which includes spa-tial patterns and temporal dynamics of hydrological variables and processes (Davison et al., 2015; Ek and Holtslag, 2004). In general, catchment models are parameterized with spatial information on soil, vegetation and topography. However, traditional approaches for eval-uation of the hydrological model performance are usually motivated with respect to dis-charge data alone. This may thus cloud model realism and hamper understanding of the catchment behavior. It is necessary to evaluate the model performance with respect to in-ternal hydrological processes within the catchment area as well as other components of wa-ter balance rather than runoff discharge at the catchment outlet only. In particular, a consid-erable amount of dynamics in a catchment occurs in the processes related to interactions of the water, soil and vegetation. Evapotranspiration process, for instance, is one of those key interactive elements, and the parameterization of soil and vegetation in water balance mod-eling strongly influences the simulation of evapotranspiration. Specifically, to parameterize the water flow in unsaturated soil zone, the functional relationships that describe the soil water retention and hydraulic conductivity characteristics are important. To define these functional relationships, Pedo-Transfer Functions (PTFs) are common to use in hydrologi-cal modeling. Opting the appropriate PTFs for the region under investigation is a crucial task in estimating the soil hydraulic parameters, but this choice in a hydrological model is often made arbitrary and without evaluating the spatial and temporal patterns of evapotran-spiration, soil moisture, and distribution and intensity of runoff processes. This may ulti-mately lead to implausible modeling results and possibly to incorrect decisions in regional water management. Therefore, the use of reliable evaluation approaches is continually re-quired to analyze the dynamics of the current interactive hydrological processes and predict the future changes in the water cycle, which eventually contributes to sustainable environ-mental planning and decisions in water management.
Remarkable endeavors have been made in development of modelling tools that provide insights into the current and future of hydrological patterns in different scales and their im-pacts on the water resources and climate changes (Doell et al., 2014; Wood et al., 2011). Although, there is a need to consider a proper balance between parameter identifiability and the model's ability to realistically represent the response of the natural system. Neverthe-less, tackling this issue entails investigation of additional information, which usually has to be elaborately assembled, for instance, by mapping the dominant runoff generation pro-cesses in the intended area, or retrieving the spatial patterns of soil moisture and evapotran-spiration by using remote sensing methods, and evaluation at a scale commensurate with hydrological model (Koch et al., 2022; Zink et al., 2018). The present work therefore aims to give insights into the modeling approaches to simulate water balance and to improve the soil and vegetation parameterization scheme in the hydrological model subject to producing more reliable spatial and temporal patterns of evapotranspiration and runoff processes in the catchment.
An important contribution to the overall body of work is a book chapter included among publications. The book chapter provides a comprehensive overview of the topic and valua-ble insights into the understanding the water balance and its estimation methods.
Moreover, the first paper aimed to evaluate the hydrological model behavior with re-spect to contribution of various sources of information. To do so, a multi-criteria evaluation metric including soft and hard data was used to define constraints on outputs of the 1-D hydrological model WaSiM-ETH. Applying this evaluation metric, we could identify the optimal soil and vegetation parameter sets that resulted in a “behavioral” forest stand water balance model. It was found out that even if simulations of transpiration and soil water con-tent are consistent with measured data, but still the dominant runoff generation processes or total water balance might be wrongly calculated. Therefore, only using an evaluation scheme which looks over different sources of data and embraces an understanding of the local controls of water loss through soil and plant, allowed us to exclude the unrealistic modeling outputs. The results suggested that we may need to question the generally accept-ed soil parameterization procedures that apply default parameter sets.
The second paper attempts to tackle the pointed model evaluation hindrance by getting down to the small-scale catchment (in Bavaria). Here, a methodology was introduced to analyze the sensitivity of the catchment water balance model to the choice of the Pedo-Transfer Functions (PTF). By varying the underlying PTFs in a calibrated and validated model, we could determine the resulting effects on the spatial distribution of soil hydraulic properties, total water balance in catchment outlet, and the spatial and temporal variation of the runoff components. Results revealed that the water distribution in the hydrologic system significantly differs amongst various PTFs. Moreover, the simulations of water balance components showed high sensitivity to the spatial distribution of soil hydraulic properties. Therefore, it was suggested that opting the PTFs in hydrological modeling should be care-fully tested by looking over the spatio-temporal distribution of simulated evapotranspira-tion and runoff generation processes, whether they are reasonably represented.
To fulfill the previous studies’ suggestions, the third paper then aims to focus on evalu-ating the hydrological model through improving the spatial representation of dominant run-off processes. It was implemented in a mesoscale catchment in southwestern Germany us-ing the hydrological model WaSiM-ETH. Dealing with the issues of inadequate spatial ob-servations for rigorous spatial model evaluation, we made use of a reference soil hydrologic map available for the study area to discern the expected dominant runoff processes across a wide range of hydrological conditions. The model was parameterized by applying 11 PTFs and run by multiple synthetic rainfall events. To compare the simulated spatial patterns to the patterns derived by digital soil map, a multiple-component spatial performance metric (SPAEF) was applied. The simulated DRPs showed a large variability with regard to land use, topography, applied rainfall rates, and the different PTFs, which highly influence the rapid runoff generation under wet conditions.
The three published manuscripts proceeded towards the model evaluation viewpoints that ultimately attain the behavioral model outputs. It was performed through obtaining information about internal hydrological processes that lead to certain model behaviors, and also about the function and sensitivity of some of the soil and vegetation parameters that may primarily influence those internal processes in a catchment. Accordingly, using this understanding on model reactions, and by setting multiple evaluation criteria, it was possi-ble to identify which parameterization could lead to behavioral model realization. This work, in fact, will contribute to solving some of the issues (e.g., spatial variability and modeling methods) identified as the 23 unsolved problems in hydrology in the 21st century (Blöschl et al., 2019). The results obtained in the present work encourage the further inves-tigations toward a comprehensive model calibration procedure considering multiple data sources simultaneously. This will enable developing the new perspectives to the current parameter estimation methods, which in essence, focus on reproducing the plausible dy-namics (spatio-temporal) of the other hydrological processes within the watershed
Revolutioniert BRICS+ das Weltfinanzsystem? Die Abkehr vom US-Dollar im Realitätscheck
Full text linkEffects of trading apps on investment behavior
Full text linkThis thesis contains three parts that are all connected by their contribution to research about the effects of trading apps on investment behavior. The primary motivation for this study is to investigate the previously undetermined consequences and effects of trading apps, which are a new phenomenon in the broker market, on the investment and risk behavior of Neobroker users.
Chapter 2 addresses the characteristics of a typical Neobroker user and a former Neobroker user and the impact of trading apps on the investment and risk behavior of their users. The results show that Neobroker users are significantly more risk tolerant than the general German population and are influenced by trading apps regarding their investment and risk behavior. Low trading fees and the low minimum investment amount are the main reasons for the use of trading apps. Investors who stop using trading apps mostly stop investing altogether. Another worrying result is that financial literacy among all groups is low and most Neobroker users have wrong conceptions about how trading apps earn money. In general, the financial literacy of all groups considered in this chapter is surprisingly low.
The third chapter investigates the effects of trading apps on investment behavior over time and compares the investment and risk behavior of Neobroker users and general investors. By using representative data of German Neobroker users, who were surveyed repeatedly over a 8-month time interval, it becomes possible to determine causal effects of the use of trading apps over time. In total, the financial literacy of Neobroker users increases with the longer use of a trading app. A worrying result is that the risk tolerance of Neobroker users rises significantly over time. Male Neobroker users gain a higher annual return (non-risk-adjusted) than female Neobroker users. In comparison to general investors, Neobroker users are significantly younger, more risk tolerant, more likely to buy derivatives and gain a higher annual return (non-risk-adjusted).
The fourth chapter analyses the impact of personality traits on the investment and risk behavior of Neobroker users. The results show that the BIG-5 personality traits have an impact on the investment behavior of Neobroker users. Two personality traits, openness and conscientiousness, stand out the most, as these two have explanatory power over various aspects of the behavior of Neobroker users. In particular, whether they buy different financial products than planned, the time they inform themselves about financial markets, the variety of financial products owned, and the reasons to use a Neobroker. Surprisingly, the risk tolerance of Neobroker users and the reasons to invest are not connected to any personal dimension. Whether a participant uses a trading app or a traditional broker to invest is respectively influenced by different personality traits
Gender Differences in Clinical Outcomes After Left Ventricular Assist Device (LVAD) Implantation – The Role of Psychosocial Risk Factors
Full text linkLeft ventricular assist devices (LVADs) have become a valuable treatment for patients with advanced heart failure. Women appear to be disadvantaged in the usage of LVADs and concerning clinical outcomes such as death and adverse events after LVAD implant. Contrary to typical clinical characteristics (e.g., disease severity), device-related factors such as the intended device strategy, bridge to a heart transplantation or destination therapy, are often not considered in research on gender differences. In addition, the relevance of pre-implant psychosocial risk factors, such as substance abuse and limited social support, for LVAD outcomes is currently unclear. Thus, the aim of this dissertation is to explore the role of pre-implant psychosocial risk factors for gender differences in clinical outcomes, accounting for clinical and device-related risk factors.
In the first article, gender differences in pre-implant characteristics of patients registered in The European Registry for Patients with Mechanical Circulatory Support (EUROMACS) were investigated. It was found that women and men differed in multiple pre-implant characteristics depending on device strategy. In the second article, gender differences in major clinical outcomes (i.e., death, heart transplant, device explant due to cardiac recovery, device replacement due to complications) were evaluated for patients in the device strategy destination therapy in the Interagency Registry for Mechanically Assisted Circulation (INTERMACS). Additionally, the association of gender and psychosocial risk factors with the major outcomes were analyzed. Women had similar probabilities to die on LVAD support, and even higher probabilities to experience explant of the device due to cardiac recovery compared with men in the destination therapy subgroup. Pre-implant psychosocial risk factors were not associated with major outcomes. The third article focused on gender differences in 10 adverse events (e.g., device malfunction, bleeding) after LVAD implant in INTERMACS. The association of a psychosocial risk indicator with gender and adverse events after LVAD implantation was evaluated. Women were less likely to have psychosocial risk pre-implant but more likely to experience seven out of 10 adverse events compared with men. Pre-implant psychosocial risk was associated with adverse events, even suggesting a dose response-relationship. These associations appeared to be more pronounced in women.
In conclusion, women appear to have similar survival to men when accounting for device strategy. They have higher probabilities of recovery, but higher probabilities of device replacement and adverse events compared with men. Regarding these adverse events, women may be more susceptible to psychosocial risk factors than men. The results of this dissertation illustrate the importance of gender-sensitive research and suggest considering device strategy when studying gender differences in LVAD recipients. Further research is warranted to elucidate the role of specific psychosocial risk factors that lead to higher probabilities of adverse events, to intervene early and improve patient care in both, women and me
Die Rechtsfigur des Indigenats in der Geschichte Preußens und Württembergs von der Zeit des Heiligen Römischen Reichs bis zur Gründung des deutschen Nationalstaats von 1871
Full text linkDer zentrale Gegenstand der Untersuchung ist die Rechtsfigur des Indigenats im Kontext der württembergischen und preußischen Staatenlandschaft. Das Indigenat lässt sich als ein Recht bestimmen, das seine potenziellen Rechtsträger maßgeblich über das Abstammungsprinzip definiert und ein Verhältnis zwischen Rechtsträger und einem übergeordneten Rechtssubjekt zum Ausdruck bringt, sei es lehns- oder standes-, staats- oder auch bundes- beziehungsweise reichsrechtlicher Natur. Der zeitliche Schwerpunkt der Betrachtung liegt auf dem 19. Jahrhundert. Es werden jedoch auch Rückblicke in die Frühe Neuzeit geworfen, weil Wandel und Kontinuität in der Entwicklung des Indigenats in einer solch langen Perspektive besonders klar hervortreten können. Die zentrale These dieser Arbeit ist, dass ein enger Zusammenhang zwischen der im 19. Jahrhundert entstehenden und bis heute geläufigen Form der Zuordnung von Menschen zum Staat und den aus diesem Verhältnis entspringenden Rechten einerseits und dem frühneuzeitlichen Indigenat andererseits besteht. Dabei kann gezeigt werden, dass Gesellschaften ihre politischen Machtpositionen gegenüber „fremdstämmigen“, etwa zuwandernden Personen abschirmten, indem sie sich auf indigenatrechtliche, ethnische Bestimmungen beriefen.The central subject of this study is the legal institution „Indigenat“ in the context of the Württembergian and Prussian states. The „Indigenat“ can be defined as a right that defines its potential legal entities primarily through the principle of descent and expresses a relationship between a legal entity and a superior legal subject, whether it is of a feudal, estate, state, federal or imperial nature. The chronological focus of this study lies on the 19th century. However, it also looks back on the early modern period because change and continuity in the development of the „Indigenat“ can emerge particularly clearly in such a long perspective. The central thesis of this study is that there is a close connection between the form of the assignment of people to the state, which emerged in the 19th century and is still common today, and the rights arising from this relationship on the one hand, and the early modern „Indigenat“ on the other. It can be shown that societies shielded their political positions of power against „foreign-born“ people such as immigrants by invoking the ethnic provisions of the „Indigenat“
Balancieren auf der ‚Brandmauer‘. Wie eine Steuersenkung in Thüringen eine Demokratiedebatte auslöste.
Full text linkExploring Financial Behavior: A multi-study thesis on adaptive markets, decision-making, comparison-based emotions, and Green Finance
Full text linkThis thesis contains four parts that are all connected by their contributions to the Efficient Market Hypothesis and decision-making literature. Chapter two investigates how national stock market indices reacted to the news of national lockdown restrictions in the period from January to May 2020. The results show that lockdown restrictions led to different reactions in a sample of OECD and BRICS countries: there was a general negative effect resulting from the increase in lockdown restrictions, but the study finds strong evidence for underreaction during the lockdown announcement, followed by some overreaction that is corrected subsequently. This under-/overreaction pattern, however, is observed mostly during the first half of our time series, pointing to learning effects. Relaxation of the lockdown restrictions, on the other hand, had a positive effect on markets only during the second half of our sample, while for the first half of the sample, the effect was negative. The third chapter investigates the gender differences in stock selection preferences on the Taiwan Stock Exchange. By utilizing trading data from the Taiwan Stock Exchange over a span of six years, it becomes possible to analyze trading behavior while minimizing the self-selection bias that is typically present in brokerage data. To study gender differences, this study uses firm-level data. The percentage of male traders in a company is the dependent variable, while the company’s industry and fundamental/technical aspects serve as independent variables. The results show that the percentage of women trading a company rises with a company’s age, market capitalization, a company’s systematic risk, and return. Men trade more frequently and show a preference for dividend-paying stocks and for industries with which they are more familiar. The fourth chapter investigated the relationship between regret and malicious and benign envy. The relationship is analyzed in two different studies. In experiment 1, subjects had to fill out psychological scales that measured regret, the two types of envy, core self-evaluation and the big 5 personality traits. In experiment 2, felt regret is measured in a hypothetical scenario, and the subject’s felt regret was regressed on the other variables mentioned above. The two experiments revealed that there is a positive direct relationship between regret and benign envy. The relationship between regret and malicious envy, on the other hand, is mostly an artifact of core self-evaluation and personality influencing both malicious envy and regret. The relationship can be explained by the common action tendency of self-improvement for regret and benign envy. Chapter five discusses the differences in green finance regulation and implementation between the EU and China. China introduced the Green Silk Road, while the EU adopted the Green Deal and started working with its own green taxonomy. The first difference comes from the definition of green finance, particularly with regard to coal-fired power plants. Especially the responsibility of nation-states’ emissions abroad. China is promoting fossil fuel projects abroad through its Belt and Road Initiative, but the EU’s Green Deal does not permit such actions. Furthermore, there are policies in both the EU and China that create contradictory incentives for economic actors. On the one hand, the EU and China are improving the framework conditions for green financing while, on the other hand, still allowing the promotion of conventional fuels. The role of central banks is also different between the EU and China. China’s central bank is actively working towards aligning the financial sector with green finance. A possible new role of the EU central bank or the priority financing of green sectors through political decision-making is still being debated