We analyze an experimental public goods game in which group members can endogenously determine whether they want to supplement a standard voluntary contribution mechanism with the possibility of rewarding or punishing other group members. We find a large and positive effect of endogenous...

We devise a new experimental game by nesting a voluntary contributions mechanism in a broader spectrum of incentive schemes. With it, we study tensions between egalitarianism, equity concerns, self-interest, and the need for incentives. In a 2x2 design, subjects either vote on or exogenously...