A Theory of Conservatism

hao li, university of toronto

Abstract

A free-rider problem arises in a group when a public decision between two alternatives must be made based on privately collected evidence, leading to insufficient effort in gathering evidence and ex ante welfare loss for the group. To alleviate the free-rider problem, the group can commit to a "conservative'' rule whereby the decision is made against the alternative favored by the group's preference or prior when evidence supports the alternative but is not preponderant. For example, if a recruitment committee is biased toward making an offer to a job candidate, either because the committee is more concerned with wrongful rejection than with wrongful hiring or because it has high prior that the candidate is qualified, then a conservative rule with a hiring standard higher than what is ex post optimal given the evidence can induce committee members to examine the candidate's record more carefully and improve the quality of the hiring decision. This result that a conservative decision rule induces greater individual effort in collecting evidence explains why sometimes groups appear overly cautious toward favored alternatives. It is further extended to heterogeneous groups and private evidence.