Incommensurability and Issue Voting

In this article, I examine several models of voter behavior that are consistent with recent work in political psychology (Fiske and Tetlock, 1997) concerning incommensurability and individuals’ reluctance to make decisions involving explicit trade-offs between competing ideals or principles. In so doing, I show that one ramification of such cognitive dissonance is policy convergence in multidimensional (i.e. multi-issue) electoral competition between two parties or candidates. Furthermore, the predicted policy outcome is a weighted median, which represents, on each issue, each voter’s preferences to the degree that he or she is likely to use that issue to choose between the candidates.