How does a citizen's decision to participate in political activism depend on the participation of others? We conduct a nation-wide natural field experiment in collaboration with a major European party during a recent national election. In a seemingly unrelated survey, we randomly provide...

Does party competition affect political activism? This paper studies the decision of party supporters to join political campaigns. We present a framework that incorporates supporters' instrumental and expressive motives and illustrates that party competition can either increase or decrease...

We study participation in right-wing rallies and counterrallies in Germany to examine strategic interactions in political movements. In the leadup to two right-wing rallies, we exogenously shift potential participants' beliefs about the turnout at the right-wing rally and left-wing counterrally,...

We develop and estimate a model of jointly optimal income taxes for different types of income. Compared to standard optimal tax formulas, optimal schedular income tax rates additionally depend on cross-elasticities between tax bases capturing fiscal externalities. We discuss two applications:...

This study reports data from a field experiment that was conducted to investigate the relevance of gift-exchange for charitable giving. Roughly 10,000 solicitation letters were sent to potential donors in the experiment. One third of the letters contained no gift, one third contained a small...

This paper studies the causal effect of status differences on moral disengagement and violence. To measure violent behavior, in the experiment, a subject can inflict a painful electric shock on another subject in return for money. We exogenously vary relative status in the realm of sexual...

Numerous signaling models in economics assume image concerns. These take two forms, as relating either to social image or self-image. While empirical work has identified the behavioral importance of the former, little is known about the role of self-image concerns. We exogenously vary self-image...

This paper investigates whether risk aversion and impatience are correlated with cognitive ability. We conduct incentive compatible choice experiments measuring risk aversion, and impatience over an annual time horizon, for a representative sample of roughly 1,000 German adults. A measure of...

A key open question for theories of reference-dependent preferences is what determines the reference point. One candidate is expectations: what people expect could affect how they feel about what actually occurs. In a real-effort experiment, we manipulate the rational expectations of subjects...