We provide evidence that long-term relationships between trading parties emerge endogenously in the absence of third party enforcement of contracts and are associated with a fundamental change in the nature of market interactions. Without third party enforcement, the vast majority of trades are...

In a recent paper Engelmann and Strobl claim that a combination of a preference for efficiency and a Rawlsian motive for helping the least well-off is far more important than inequity aversion. Here we show that the relevance of the efficiency motive is largely restricted to students of...

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 examines how the presence of a non-negligible fraction of reciprocally fair actors changes the provision of incentives through contracts. We provide experimental evidence that principals have a strong preference for less complete contracts although the standard self-interest model...

Most economic models are based on the self-interest hypothesis that assumes that all people are exclusively motivated by their material self-interest. In recent years experimental economists have gathered overwhelming evidence that systematically refutes the self-interest hypothesis and suggests...

We show experimentally that fairness concerns may have a decisive impact on both the actual and the optimal choice of contracts in a moral hazard context. Explicit incentive contracts that are optimal according to self-interest theory become inferior when some agents value fairness. Conversely,...

Most economic models are based on the self-interest hypothesis that assumes that all people are exclusively motivated by their material self-interest. In recent years experimental economists have gathered overwhelming evidence that systematically refutes the self-interest hypothesis and suggests...

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...

In this paper we show that a simple model of fairness preferences explains major experimental regularities of common pool resource (CPR) experiments. The evidence indicates that in standard CPR games without communication and without sanctioning possibilities inefficient excess appropriation is...

Engelmann and Strobel (AER 2004) question the relevance of inequity aversion in simple dictator game experiments claiming that a combination of a preference for efficiency and a Rawlsian motive for helping the least well-off is more important than inequity aversion. We show that these results...