Substantial evidence suggests the behavioral relevance of social preferences and also the importance of social influence effects ("peer effects"). Yet, little is known about how peer effects and social preferences are related. In a three-person gift-exchange experiment we find causal evidence...

We use skin conductance responses and self-reports of hedonic valence to study the emotional basis of cooperation and punishment in a social dilemma. Emotional reaction to free-riding incites individuals to apply sanctions when they are available. The application of sanctions activates a...

We investigate the impact of various audit schemes on the future provision of public goods, when contributing less than the average of the group is sanctioned exogenously and the probability of an audit is unknown. We study how individuals update their beliefs about the probability of being...

Development of human societies requires cooperation among unrelated individuals and obedience to social norms. Although punishment is widely agreed to be potentially useful in fostering cooperation, many recent results in psychology and economics highlight punishments' failures in this regard....

We test if cooperation is promoted by rank-order competition between groups in which all groups can be ranked first, i.e. when everyone can be a winner. This type of rank-order competition has the advantage that it can eliminate the negative externality a group's performance imposes on other...

Charles Darwin (1874) stated that "women are less selfish but men are more competitive". Very recent papers (Eckel & Grossman, 1998, 2001 or Andreoni and Vesterlund 2001, among others) have shown the relevance of gender in altruism in both ultimatum and dictator games. In this paper we analyze...

In this paper, we analyze how kinship among family members affects intergenerational cooperation in a public good game. 165 individuals from 55 families, comprising three generations (youths, parents, and grandparents), play a public good game in three different treatments: one in which three...

We test whether humans are intuitively inclined to cooperate with or punish strangers using a natural field experiment. We exogenously vary the time available to help a stranger in an everyday situation. Our findings suggest that subjects intuitively tend to help but behave more selfishly as...

We investigate whether there is a link between conditional cooperation and betrayal aversion. We use a public goods game to classify subjects by type of contribution preference and by belief about the contributions of others; and we measure betrayal aversion for different categories of subject....

We investigate in a laboratory setting whether revealing information on the intelligence of both players affects behavior in repeated games. We study the Prisoners' Dilemma (PD) and Battle of Sexes (BoS) as they cover a large set of the interesting scenarios generated by repeated games of two...