We report the results of an experimental study that compares voting mechanisms in the provision of public goods. Subjects can freely decide how much they want to contribute. Whether the public good is finally provided is decided by a referendum under full information about all contributions. If...

Collusive agreements are often observed in procurement auctions. They are probably more easily achieved when competitors’ costs are easily estimated. If, however, the individual costs of bidders are private information, effective ring formation is difficult to realize. We compare...