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...

In public good provision, privileged groups enjoy the advantage that some of its members find it optimal to supply a positive amount of the public good. However, their inherent asymmetric nature may make the enforcement of cooperative behavior through informal sanctioning harder to accomplish....