are a widely applied economic experiments. In a public goods game, a group of people is endowed with resources which they can either place in a private or a joint account (public good). In a standard linear voluntary contributions public goods game, all benefits are internalised from the private account, but only a fraction is internalised from the group account. However, the group account generates additional benefits, creating a social dilemma (a clash between self-interest and group interest) where it is individually rational to free-ride on the contributions of others, but socially optimal to contribute everything.

In Contracts2.0 we will use public goods games to investigate the impact of contract characteristics on collective decision-making.