糖心原创

(joint with Senior Academic Seminar Series)

Growing Groups, Cooperation and the Rate of Entry

Eva Ranehill, Frédéric Schneider and Roberto A. Weber

Abstract

We study the stability of voluntary cooperation to entry by individuals coming from groups with low cooperation rates. We investigate the effect of varying entry rates on sustained cooperation. In a finitely-repeated public good game with economies of scale, we initially allot participants to small, “High-cooperation” groups and large, “Low-cooperation” groups. We then study movement from the “Low” groups into the “High” groups under two main treatment conditions that vary the rate of movement. We find that fast growth disrupts efficient public good provision; but when moved in slowly, members of “failed” groups adapt to contribution levels in cooperative groups. This behavior is generally consistent with a belief-driven explanation similar to Fischbacher and Gächter (2010). In a third condition, in which participants in the “High” group decide on the rate of entry by voting, growth generally occurs slowly but stops short of the efficient group size. Interestingly, newcomers, not incumbents, veto further entry. We conclude that the right rate of entry can greatly facilitate cooperation, but that overly cautious expansion may limit the realization of potential gains from growth.

Keywords

Voluntary cooperation, experiment, public good game

JEL Classification

C92, C72