Conformity in voting

Abstract

A group of agents has to decide whether to accept or reject a proposal. Agents vote in favor of or against the proposal and, if the number of agents in favor is greater than a certain threshold, the proposal is accepted. Conformist agents vote based on not only their opinion but also the votes of other agents. Independent agents consider only their own opinions. If all agents are conformists and vote simultaneously, there are undominated Nash equilibria in which the decision is different from that obtained if all agents vote for their opinions. Next, we provide the number of independent agents sufficient to obtain, in any equilibrium, the decision obtained when all agents vote for their opinions. This number depends on the total number of agents, the threshold, and the conformity measure. If agents vote sequentially, the voting behavior of conformist agents does not affect the decision.