Risk and Inequality Aversion in Social Dilemmas.

We experimentally investigate cooperative behavior in a social dilemma situation, where the socially efficient outcome may be encouraged by risk aversion and/or inequality aversion.The first part of our experiment is devoted to the elicitation of subjects' aversion profile, taking care to not confuse the two dimensions. Subjects are then grouped by three according to their aversion profiles, and interact in a repeated social dilemma game. In this game, agents are characterised by a social status so that higher the agent's status, higher will be her earnings. Cooperation is costly for a majority of agents at each period, but statuses can be reversed in future periods. We show that cooperation is strongly influenced by the group's aversion profile. Groups averse in both dimensions cooperate more than groups averse in only one dimension. Moreover cooperation seems to be more affected by risk aversion, whereas one might interpret cooperative behavior as an inequality averse or altruistic attitude.