Aggregating Information by Voting: The Wisdom of the Experts versus the Wisdom of the Masses

Abstract

This article analyzes participation and information aggregation in a common-value election with continuous private signals. In equilibrium, some citizens ignore their private information and abstain from voting, in deference to those with higher-quality signals. Even as the number of highly informed peers grows large, however, citizens with only moderate expertise continue voting, so that voter participation remains at realistic levels (e.g. 50 to 60 percent, for simple examples). The precise level of voter turnout, along with the margin of victory, are determined by the distribution of expertise. Improving a voter's information makes her more willing to vote, consistent with a growing body of empirical evidence, but makes her peers more willing to abstain, providing a new explanation for various empirical patterns of voting. Equilibrium participation is optimal, even though the marginal voter may have very little (e.g. below-average) expertise, and even though nonvoters' information is not utilized.