We study the role of an enforcer in the effectiveness of selective incentives in solving the collective action problem when groups take part in a contest. Cost functions exhibit constant elasticity of marginal effort costs. If prize valuations are homogeneous, our source of heterogeneity induces...

This paper examines characteristics of cooperative behavior in a repeated, n-person, continuous action generalization of a Prisoner's Dilemma game. When time preferences are heterogeneous and bounded away from one, how "much" cooperation can be achieved by an ongoing group? How does group...