Recent work in experimental economics on the effectiveness of rewards and punishments for promoting cooperation mainly examines decentralized incentive systems where all group members can reward and/or punish one another. Many self-organizing groups and societies, however, concentrate the power...

This paper presents data from experiments with a linear voluntary contributions mechanism for public goods conducted in Japan, the Netherlands, Spain and the USA. The same experimental design was used in the four countries. Our 'contribution function' design allows us to obtain a more complete...