A new approach for modelling strategic voting in multiparty elections

Whether citizens vote strategically, using their votes to defeat their least-preferred candidate, or vote sincerely, voting for their first choice among the alternatives, is a question of longstanding interest. We offer two innovations in searching for the answer to this question. First, we begin with a more consistent model of sincere voting in multiparty democratic systems than has been presented in the literature to date. Secondly, we incorporate a new operationalization of the objective potential for strategic behaviour. We offer a test of strategic voting in the 1987 British general election based on the variance in strategic setting across constituencies in Britain. We allow voters to use available information about the relative standings of parties in their constituency in deciding whether or not to cast a strategic vote. We estimate a lower level of strategic voting than many other methods have estimated. We also demonstrate that the use of self-reported vote motivation causes errors in estimating the amount of strategic voting, and that this problem is exacerbated the further from the election the self-report is obtained.