Voluntary Contributions to a Public Good: When and How Much?

Abstract

We analyze voluntary public good contributions with incomplete information. A fundraiser chooses whether to disclose or withhold contributions as they occur, and two contributors choose the size and (eventually) the order of their contributions. Contributions made without announcement—thus simultaneous—minimize free-riding incentives of contributors with low valuations, whereas contributions with disclosure of past donations—thus sequential—minimize those of contributors with high valuations. To maximize aggregate contributions, a fundraiser permits sequential contributions when high valuations are prevalent or significantly exceed low valuations. Otherwise, simultaneous contributions are preferred.