Guilt and participation

How does guilt affect participation in providing public goods? We characterise and analyse completely mixed symmetric equilibria (CMSE) in participation games where players are guilt averse. We find that relative to material preferences, guilt aversion can: facilitate the existence of CMSE; increase or decrease participation; and imply that group size has a non-monotonic effect on participation. Using our equilibrium characterisation we also re-analyse experimental data on participation games and find a low, but positive, guilt sensitivity parameter.