Explaining the evolution and maintenance of cooperation among unrelated individuals is one of the fundamental problems in biology and the social sciences. Recent experimental evidence suggests that altruistic punishment is an important mechanism to maintain cooperation among humans. In this...

We examine the effectiveness of the individual-punishment mechanism in larger groups, comparing groups of four to groups of 40 participants. We find that the individual punishment mechanism is remarkably robust when the marginal per capita return (MPCR), i.e. the return to each participant from...

To study the persistence of cultural norms that mandate respect towards the elder, we conducted an artefactual field experiment in two cities in Ghana. Using a public good game with third-party punishment, we find that punisher's age is an important determinant of cooperation. Our results...

According to economists, severe legal sanctions deter violations of the law. According to legal scholars, people may obey law backed by mild sanctions because of norm-activation. We experimentally investigate the effects of mild and severe legal sanctions in the provision of public goods. The...

Experiments using the public goods game have repeatedly shown that in cooperative social environments, punishment makes cooperation flourish, and withholding punishment makes cooperation collapse. In less cooperative social environments, where antisocial punishment has been detected, punishment...