Provision of step-level public goods: Effects of greed and fear of being gypped

In an attempt to study the differential effects of two motives on contribution to the provision of public goods, 12 groups of five subjects each participated in three multiple-trial, social dilemma games. Each subject received a fixed endowment, e, and then decided independently and anonymously whether to contribute it to a monetary public good. The public good, r, was provided to all five group members if three or more contributed; it was not provided, otherwise. In the first condition both major motives for not contributing—a desire to free ride (greed) and a fear of wasting one's resources (fear)—were present. A second condition eliminated fear but maintained greed, whereas a third condition eliminated greed but kept fear. It was found that both fear and greed motivate noncooperative behavior, but that the latter motive predominated. Individual and group data support a model of public good provision proposed by A. Rapoport (1987, Psychological Review, 94, 74–83).