It is now generally accepted that some people are more altruistic, more trusting, or more reciprocal than others, but it is still unclear whether these differences are innate or a consequence of nurture. We analyse the correlation between handedness and social preferences in the lab and find...

We propose a social welfare function to evaluate a profile of income streams and compare the welfare gain of the actual profile relative to the income profile where the individual receives his first period income in each period. We derive necessary and sufficient conditions for the welfare gain...

We examine settings - such as litigation, labor relations, or arming and war - in which players first make non-contractible up-front investments to improve their bargaining position and gain advantage for possible future conflict. Bargaining is efficient ex post, but we show that a player may...

Male and female choices differ in many economic situations, e.g., on the labor market. This paper considers whether such differences are driven by different attitudes towards competition. In our experiment subjects choose between a tournament and a piece-rate pay scheme before performing a real...

Humans make decisions jointly with others. They share responsibility for the outcome with their interaction partners. Today, more and more often the partner in a decision is not another human but, instead, a machine. Here we ask whether the type of the partner, machine or human, affects our...

Substantial evidence has accumulated in recent empirical works on the limited ability of the Nash equilibrium to rationalize observed behavior in many classes of games played by experimental subjects. This realization has led to several attempts aimed at finding tractable equilibrium concepts...

We examine whether belief-based preferences - caring about what transgressors believe - play a crucial role in punishment decisions: Do punishers want to make sure that transgressors understand why they are being punished, and is this desire to affect beliefs often prioritized over distributive...