Punishment in a Linear Public Good Game with Productivity Heterogeneity

Abstract

Although it is widely recognized that sanction increases cooperation in a public good game, comparatively little attention has been paid to a scenario in which agents have heterogeneous productivities (i.e. asymmetric impact on the group account). This paper examines the extent to which sanction works in this scenario by varying marginal per capita return (MPCR) among group members. Experimental results indicate that in the absence of sanctions, productivity heterogeneity hampers cooperation. Allowing punishment in these groups significantly enhances average contributions of group members, but does not increase welfare. In groups in which cooperation is highly successful, high-productivity agents actively punish low-productivity agents in initial periods. However, conditional on individual contributions, high-productivity agents receive more punishment, and behave more responsively by raising their contributions in the next period. The results mirror the reality in which elites in a society are under higher pressure, since their choices are likely to have a deeper impact on a society.