There is strong evidence that people exploit their bargaining power in competitive markets but not in bilateral bargaining situations. There is also strong evidence that people exploit free-riding opportunities in voluntary cooperation games. Yet, when they are given the opportunity to punish...

One of the most basic questions in economics concerns the effects of competition on market prices. We show that the neglect of both fairness concerns and decision errors prevents a satisfactory understanding of how competition affects prices. We conducted experiments which demonstrate that the...

This paper reports on a two-task principal-agent experiment in which only one task is contractible. The principal can either offer a piece-rate contract or a (voluntary) bonus to the agent. Bonus contracts strongly outperform piece rate contracts. Many principals reward high efforts on both...

Politik und öffentliches Bewusstsein werden zunehmend durch ökonomische Theorien und Handlungsvorschläge mitbestimmt. Kaum ein anderes erkenntnis- und handlungsleitendes Modell hat daher einen vergleichbaren Einfluss wie das Konzept des Homo Oeconomicus. Durch die Entwicklung experimenteller...

We report on several experiments on the optimal allocation of ownership rights. The experiments confirm the property rights approach by showing that the ownership structure affects relationship-specific investments and that subjects attain the most efficient ownership allocation despite starting...

This paper shows that reciprocity has powerful implications for many economic domains. It is an important determinant in the enforcement of contracts and social norms and enhances the possibilities of collective action greatly. Reciprocity may render the provision of explicit incentive...

Recently developed models of fairness can explain a wide variety of seemingly contradictory facts. The most controversial and yet unresolved issue in the modeling of fairness preferences concerns the behavioral relevance of fairness intentions. Intuitively, fairness intentions seem to play an...

We show that concerns for fairness may have dramatic consequences for the optimal provision of incentives in a moral hazard context. Incentive contracts that are optimal when there are only selfish actors become inferior when some agents are concerned about fairness. Conversely, contracts that...

This paper reports the results of a series of competitive labour market experiments in which subjects have the possibility to reciprocate favours. In the high stake condition subjects earned between two and three times their monthly income during the experiment. In the normal stake condition the...

This paper shows that identical offers in an ultimatum game generate systematically different rejection rates depending on the other offers that are available to the proposer. This result casts doubt on the consequentialist practice in economics to define the utility of an action solely in terms...