Factors mediating residual effects of group size in social dilemmas.

Abstract

Tested the hypothesis that when no personal contacts were permitted among participants in a 1-shot dilemma situation, the residual effect of group size would be mediated either by expectations of other members' contributions or by the efficacy of altruistic actions. Human subjects: 88 normal male and female Japanese adults (some were undergraduate students). Group size was varied from 2 to 501 (Exp I) or from 3 to 36 (Exps II and III). The average contribution as a function of group size and contingency type (unilateral-rewarding or mutual-rewarding), the frequency of Ss who changed/did not change actual contribution level as a function of expectation of other members' contribution levels, and the influence of efficacy of altruism on observed residual effect were analyzed. (English abstract) (PsycINFO Database Record (c) 2002 APA, all rights reserved)