E-Dissertationen

Essays in Nonparametric Econometrics

2026-03-31T00:00:00Z

Essays in Nonparametric Econometrics Scherer, Jan This dissertation consists of three chapters on inference in various non- and semiparametric problems. The chapters are self-contained and can be read separately. Each chapter ends with an appendix that collects the proofs and technical details.
In the first chapter, we study inference on parameters of the form ϕ(θ₀), where ϕ is a known directionally differentiable transformation and θ₀ is an unknown parameter. We focus on settings, where θ₀ is an unknown function estimated using some nonparametric estimator θ_n. As many nonparametric estimators do not converge in distribution, existing extensions to the Delta method are not applicable in our setting. We propose to use strong approximations to the distribution of θ_n as an alternative concept to convergence in distribution. Further, we present a notion of directional differentiability which is sufficiently flexible to handle the irregularity of nonparametric estimators. These concepts enable us to derive a new Delta method which approximates the distribution of the plug-in estimator ϕ(θ_n). Since these distributional approximations are rarely pivotal, we suggest a simulation-based estimator and provide conditions for its consistency. Confidence intervals based on this estimator are shown to provide local size control under conditions on the directional derivative of ϕ. We illustrate the applicability of our results in two examples and study its finite sample performance in a simulation study.
Anti-concentration bounds play an important role in the modern theory on confidence intervals and testing in settings such as high-dimensional and nonparametric statistics. In the second chapter, we establish such a bound for sublinear and continuous functionals of tight Gaussian random vectors in real-valued Banach spaces. The bound is dimension-free and therefore equally applies to finite- as well as infinite-dimensional settings. It imposes only weak restrictions on the covariance structure of the Gaussian vectors. As an application of our anti-concentration bound, we derive Berry-Esseen type bounds for sublinear and continuous functionals of high-dimensional mean vectors and kernel-type estimators.
The last chapter, which is joint work with Michael Vogt, studies estimation and inference in the high-dimensional partially linear model Y = δ + m(T) + X^T β + ϵ, where m is a smooth unknown function and β a sparse unknown regression parameter. The dimension of the covariates X is allowed to increase with the sample size and in particular is allowed to be larger than the sample size. We propose an estimator of β which attains the same rates as the infeasible Lasso estimator which knows the unknown function m. Further, we show that ad-hoc estimators of m might be biased due to the estimation of the high-dimensional parameter β and propose an orthogonalized Nadaraya-Watson estimator of m which effectively decreases this high-dimensional bias. This estimator is shown to converge at the same rates as an infeasible Nadaraya-Watson estimator which knows the true value of β. Based on this estimator, we propose a test for the hypothesis that m = 0 which generalizes the idea of significance testing in linear models to allow for general nonlinear effects of T on Y. Moreover, we propose a consistent multiplier bootstrap in order to set the critical values and show uniform consistency of the resulting set against local Hölder balls. We study the finite sample performance of our proposed test in a simulation study and demonstrate its good debiasing and power properties.

Essays in Applied Microeconomics

2026-02-03T00:00:00Z

Essays in Applied Microeconomics Laubel, Alexander This dissertation consists of three self-contained chapters of original research – two of which are single-authored and one with a fellow PhD student – and contributes predominantly to behavioral economics and experimental economics, with one chapter also in cultural economics.
Chapter 1, "Retelling and Memory", investigates whether biased retelling of previously encountered information makes memory of the original information biased, too. In a randomized controlled experiment, participants first evaluated hypothetical products based on brief descriptions. They were then instructed to retell these descriptions either accurately or in an overly optimistic way (between-subjects treatment variation). One day later, all participants were asked to retell the original descriptions accurately and to recall their initial ratings. Both the day-2 ratings and the day-2 retellings (as assessed by two independent human coders) revealed a large and highly significant treatment effect. That is, subjects who had retold the descriptions in an overly optimistic way on day 1 also provided exaggerated ratings and retellings on day 2 even though incentives at that point required accuracy. A robustness experiment tested whether this bias was already present immediately after the first retelling, thus assessing whether the effect reflects a genuine memory distortion. While a statistically significant average treatment effect immediately after retelling was found, it was (i) substantially smaller in magnitude, (ii) more sensitive to outliers, and (iii) not accompanied by significant distributional differences. This study provides causal evidence that biased retelling distorts memory, contributing a novel insight to the economics literature. The findings suggest that in contexts where people are likely to retell past experiences or information in a biased manner, even memory recalled under accuracy incentives may be systematically distorted. Such effects may be particularly relevant in financial, labor market or discrimination-related settings.
Chapter 2, "Illusion of Control in a Complex Environment", examines whether people believe desirable outcomes are more likely when they are more engaged in a process, even when this engagement is only pseudo-relevant. Specifically, it is tested whether the method of generating a random outcome (via a physical die vs. a computer) affects beliefs about winning a board game. To cleanly identify effects, beliefs are elicited not only from the players but also from an independent observer. Such a tendency – known as illusion of control – has been studied extensively in psychology (beginning with Langer, 1975), but has received comparatively less attention in economics. While the psychology literature consistently finds evidence for illusion of control (Presson and Benassi, 1996; Stefan and David, 2013), findings in economics have been more mixed. The results of this chapter align with the latter: in several specifications, no treatment effect for the main incentivized belief about winning the board game is observed (insignificant and point estimates close to zero), casting doubt on the robustness of the illusion-of-control findings in psychology. There is borderline significant evidence that participants who used a physical die perceived skill as more important (relative to luck), but this pattern is not limited to players and is also present among observers.
Chapter 3, "Parents' Beliefs About Cultural Transmission" (co-authored with Paul Behler), presents a dedicated survey of parents and offers two main contributions. The first part of the chapter presents detailed descriptive evidence on, for example, which agents or institutions parents believe matter for which traits at different ages, which traits they prefer to shape, and what goals and methods they pursue in this shaping. This addresses an important gap, as little is known about parents' beliefs and preferences concerning the non-genetic shaping of children's attitudes and character traits. Second, the chapter engages with the literature in cultural economics by testing two key assumptions: imperfect empathy and substitutability (Bisin and Verdier, 2001, 2011). We empirically assess whether parents indeed evaluate their children's choices using their own (the parents') preferences (imperfect empathy) and whether they invest more effort in cultural transmission when their goals are misaligned with their child's social environment (substitutability). We find robust evidence that approximately 60% of parents exhibit imperfect empathy. In contrast, we do not find support for substitutability: parents' transmission effort is not significantly affected by whether the environment is aligned, and the extremeness of their choices, if anything, moves in an anti-substitutability direction. That is, they tend to align with the perceived environment rather than compensating for it, particularly among liberal parents.

Essays in Bargaining, Auctions and Payments

2026-01-27T00:00:00Z

Essays in Bargaining, Auctions and Payments Sorbera, Silvio This dissertation studies three game-theoretical models in bargaining, auctions, and payment systems.
The first chapter examines reputational bargaining when one party may possess full information about the rationality of the opponent. The model highlights the role of second-order beliefs and studies whether a fully informed player has incentives to reveal their information through a fair offer. The analysis shows that multiple equilibria can arise, including equilibria in which rational players strategically avoid revealing their information to preserve reputational advantages.
The second chapter analyzes simultaneous participation in sealed-bid auctions with unit-demand bidders. Unlike standard auction models, the setting admits no symmetric pure-strategy equilibrium. The chapter establishes the existence of symmetric mixed-strategy equilibria and shows that bidders optimally place bids in all available auctions with probability one.
The third chapter studies card acceptance and payment choice in a model where consumers can search for merchants that accept card payments. Despite transaction fees, sellers may optimally accept cards to attract customers. The model features multiple equilibria with different levels of card acceptance. A calibrated extension using European payment diary data is employed to evaluate policy interventions, showing that subsidies to card usage may generate unintended general equilibrium effects that reduce card adoption.

Forderungskollision

2025-01-01T00:00:00Z

Forderungskollision Albers, Gregor Wenn ein Schuldner nicht all seine Gläubiger befriedigen kann oder muss, kollidieren ihre Forderungen. Lässt die Rechtsordnung die Gläubiger konkurrieren, weil sie hofft, dass alles gut gehen wird, oder weil sie einen Eingriff als illegitim oder unpraktikabel ansieht? Ordnet sie gleichmäßige Befriedigung an oder spricht sie bestimmten Forderungen Vorrang zu? Während die Insolvenz viel Aufmerksamkeit auf sich zieht, fehlen Prinzipien für das allgemeine Problem. Dabei stellt es sich in verschiedensten Kontexten, etwa bei Leistungsstörungen, Gefährdungshaftung, Haftpflichtversicherungen, Nachlassverbindlichkeiten, der Haftung des Kommanditisten und nach Unternehmensspaltungen. Auf der Grundlage einer historischen Betrachtung entwirft Gregor Albers ein Modell dafür, wann welches Prinzip Anwendung findet. Zudem macht er Vorschläge für die Ausgestaltung des Wettlaufs und die Behandlung von Verteilungsfehlern nach dem Modell des Anfechtungsrechts.