Voluntary Participation in a Mechanism Implementing a Public Project

In this study, a participation game in a mechanism to implement a public project is considered; in this game, agents decide simultaneously whether they will participate in the mechanism or not. We characterize the sets of participants at strict Nash equilibria, strong equilibria, and coalition-proof equilibria of the participation game. The three sets of equilibria are shown to coincide and exist. All the equilibrium allocations are Pareto efficient at any one of three notions of equilibria. However, if the public good can be provided in multiple units or if there are multiple projects, then these sets may fail to coincide.