Information Aggregation, Costly Voting and Common Values

In a model of majority voting with common values and costly but voluntary participation, we show that in the vicinity of equilibrium, it is always Pareto-improving for more agents, on the average, to vote. This demonstrates that the negative voting externality identified by Borgers(2001) in the context of private values is always dominated by a positive informational externality. In addition, we show that multiple Pareto-ranked voting equilibria may exist and moreover, majority voting with compulsory participation can Pareto dominate majority voting with voluntary participation. Finally, we show that the inefficiency result is robust to limited preference heterogeneity.