Strategic Voting Under Conditions of Uncertainty: A Re-Evaluation of Duverger's Law

Political scientists have long recognized that the number of parties in a country influences the way that interests are represented in that country. One explanation for the number of parties in a system relies on the idea of strategic voting, i.e. voters may not want to ‘waste a vote’ by voting for a third party. However, work in this area does not address the role of an important factor that may affect party systems through strategic voting: information. Without polls, how could voters know which parties were likely to win, and hence how to vote strategically? Using an agent-based model, this article assesses the role that information plays in shaping the party system through strategic voting. The results of this model demonstrate that, contrary to Duverger's Law, more than two parties may emerge in single-member plurality systems, even when all voters are strategic.