Inequities in access to and use of shared resources in social dilemmas.

Abstract

In this study we investigated the effects of inequities in access to and use of shared resources on harvest decisions and preferences for structural change in resource dilemmas. Subjects, in groups of six, harvested resource units from a common, replenishable resource pool over 10 trials. Following the harvest trials, subjects were asked to vote on how to conduct the second session. The variables in this 2x2x2 factorial design were (a) access to the resource pool, (b) perceived resource use, and (c) perceived inequity (variance) in other group members' harvests. The hypothesis was that highvariance subjects, when placed in a situation where harvest inequities could be attributed to structural features of the free-access system (i.e., access differences), would demonstrate a stronger preference for equality-restoring decision structures than would low-variance subjects. The results offered little support for this prediction overall; the variance manipulation had the predicted effect only among high-access subjects in the overuse condition. As expected, the access and use variables had independent effects on preferences for structural change. Harvest decisions were mediated by the three design variables in the manner predicted by a three-factor model which assumes that harvest size will be governed by self-interest, a desire to use the common resource responsibly, and conformity to implicit group norms.