How is donation behaviour affected by the donations of others?

This paper describes a natural field experiment investigating voluntary contributions to a public good. The setting was an art gallery where admission was free, but donations could be deposited into a transparent box in the foyer. We manipulated the social information available to patrons by altering what was visible in the donation box. In particular, we investigated four treatments: one with primarily a few large denomination bills, one with several small denomination bills, one with a large amount of coinage, and one empty. The social information provided had a significant impact on donation composition, frequency, and value.