Because costly punishment is not credible, subgame perfection suggests that punishment will not deter free riding, regardless of the size or structure of groups. However, experiments show that people will punish free riders, even at considerable cost. To examine the implications of agents who...

We augment the standard cartel formation game from non-cooperative coalition theory, often applied in the context of international environmental agreements on climate change, with the possibility that singletons support coalition formation without becoming coalition members themselves. Rather,...

One lingering puzzle is why voluntary contributions to public goods decline over time in experimental and real-world settings. We show that the decline of cooperation is driven by individual preferences for imperfect conditional cooperation. Many people's desire to contribute less than others,...

Many people contribute to public goods but stop doing so once they experience free riding. We test the hypothesis that groups whose members know that they are composed only of 'like-minded' cooperators are able to maintain a higher cooperation level than the most cooperative, randomly-composed...