The Study of Strategic Voting

This chapter stresses the necessity of distinguishing between a strategic vote and a strategic voter. The sincere voter always casts a sincere vote, while the strategic voter casts a sincere or strategic vote depending on the context and the voting rule. This leads to two definitions of strategic voting: a broad one, where a strategic vote is one that is partly based on expectations about the outcome of the election, and a narrow one, where a strategic vote also entails not voting sincerely. The chapter then reviews three types of empirical research that differ with respect to the type of data used: the observation of electoral outcomes, survey data, and lab experiments. That literature has confirmed that indeed some voters cast a strategic vote, though many studies have found most votes to be sincere. That research has also shown that there is some degree of strategic voting under all kinds of voting rules; that, contrary to conventional wisdom, there is as much strategic voting under proportional representation as under plurality rule; and that the propensity to vote strategically depends very much on the type of information that is available.

Polarization, Partisan Preferences and Strategic Voting

In this article, we study how polarization affects the propensity of supporters of non-viable parties to cast a strategic vote. To do so, we rely on Canadian election panel surveys from the Making Electoral Democracy Work project that were specifically designed to identify strategic voting. We find that the polarization between viable parties increases the probability of a supporter of a non-viable party casting a strategic vote, because it increases how much she likes her favourite viable party, and decreases how much she dislikes her least favourite viable party. Polarization thus increases strategic voting because it alters partisan preferences.

Strategic Vote Trading in Power Sharing Systems

This paper studies decentralized vote trading in a power sharing system that follows the rules of strategic market games. In particular, we study a two-party election in which prior to the voting stage, voters are free to trade votes for money. Voters hold private information about both their ordinal and cardinal preferences, whereas their utilities are proportionally increasing in the vote share of their favorite party. In this framework, we prove generic existence of a unique full trade equilibrium (an equilibrium in which nobody refrains from vote trading). Moreover, we argue that vote trading in such systems unambiguously improves voters' welfare. (JEL C72, D71, D72, D82)