We study the. Incentive effects of endogenous group formation in a voluntary contributon experiment. Subjects are given information on the past contributions of others and allowed to express a preference for partners. On the basis of the stated preferences new groups are formed. We find that the...

The prospect of receiving a monetary sanction for free riding has been shown to increase contributions to public goods. We ask whether the impulse to punish is unresponsive to the cost to the punisher, or whether, like other preferences, it interacts with prices to generate a conventional demand...

When subjects can make non-binding announcements of possible contributions to a public good numerically, there is no effect on average level of contributions in a public goods experiment relative to play without announcements. But a detailed analysis of this experiment shows that pre-play...

In a public goods experiment with the opportunity to vote to expel members of a group, we found that contributions rose to nearly 100% of endowments with significantly higher efficiency compared with a noexpulsion baseline. Expulsions were strictly of the lowest contributors, and there was an...

Mounting evidence suggests that the outcomes of laboratory public goods games, and collective action in firms, communities, and polities, reflect the presence in most groups of individuals having differing preferences and beliefs. We designed a public goods experiment with targeted punishment...