Throughout human history, informal sanctions played a key role in the enforcement of social norms and the provision of public goods. However, a considerable body of evidence suggests that informal peer sanctions often cause large efficiency costs. This raises the question whether alternative...

Throughout human history, informal sanctions by peers were ubiquitous and played a key role in the enforcement of social norms and the provision of public goods. However, a considerable body of evidence suggests that informal peer sanctions cause large collateral damage and efficiency costs....

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....

Do individuals trained in law enforcement punish or reward differently from typical student subjects? We analyze norm enforcement behavior of newly appointed police commissioners in both a Voluntary Contribution Mechanism game and a Common Pool Resource game. Our experimental design includes...

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...

We study cooperation within and between groups in the laboratory, comparing treatments in which two groups have previously been (i) in conflict with one another, (ii) in conflict with a different group, or (iii) not previously exposed to conflict. We model conflict using an inter-group Tullock...

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 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...

Social media has made anonymized behavior online a prevalent part of many people's daily interactions. The implications of this new ability to hide one's identity information remain imperfectly understood. Might it be corrosive to human cooperation? This paper investigates the possibility that a...

Using a negatively framed public good game, we study the cooperative behavior of individuals who reintegrate their group after being excluded by their peers. We manipulate the length of exclusion and whether this length is imposed exogenously or results from a vote. We show that people are...