Predicting Ambiguity: Costs, Benefits, and Party Competition.

We present a formal model of party competition to explain differences in party ideological ambiguity. Existing works generally argue that parties are more or less ambiguous depending on whether their supporters are risk-acceptant or risk-averse. Our model explores more fully strategic choice of ambiguity by considering nonelectoral benefits to ambiguity--that is, party elite recruitment and retention. In terms of costs, we assume that all voters are risk-averse, who therefore prefer less ideological ambiguity. Explicitly considering both costs and benefits derives our hypotheses and highlights the importance of party competition--ambiguity is influenced by the proximity to a party's closest ideological competitor. An empirical analysis of twenty-eight European countries supports our hypotheses. [ABSTRACT FROM AUTHOR]