A novel version of a Voluntary Contribution Mechanism game tests how player cooperation responds to changes in incentives, i.e., payoffs that depend on performance relative to different reference groups. Cooperation is greatest when players are competing against players in other four-person...

Managers of public water companies present themselves and are seen as public servants maximizing public welfare. Because water is rarely allocated through market mechanisms, this maximization requires that managers cooperate in a bureaucratic version of a social dilemma. Members of the...