An Activist Model of Democracy

The focus of this paper is that actual political systems do not appear to satisfy the property of convergence to an electoral center that is often predicted by formal vote models. The key theoretical idea is that the convergence result need not hold if there is an asymmetry in the electoral perception of the “quality” of party leaders (Stokes 1992). The average weight given to the perceived quality of the leader of a party is called the party’s valence. In empirical models, a party’s valence is usually assumed to be exogenous, and independent of the party’s position. In general, valence reflects the overall degree to which the party is perceived to have shown itself able to govern effectively in the past, or is likely to be able to govern well in the future (Penn 2003). The motivation for the development of the activist stochastic electoral model, which is presented in this paper, is based on a set of empirical results from multinomial logit electoral estimation for the Netherlands, Britain and the United States. These empirical analyses, coupled with theoretical results, indicate that the stochastic model with exogenous valence cannot fully account for the divergence observed in a number of elections in these polities. Theorem 5.2, presented below, gives the necessary and sufficient conditions for convergence to the electoral mean in the stochastic model with exogenous valence. The necessary condition is that a convergence coefficient, c, is bounded above by the dimension, w, of the policy space, while a sufficient condition is that the coefficient is bounded above by 1. This coefficient is defined in terms of the difference in exogenous valences, the “spatial coefficient” and the electoral variance. The empirical work on Britain and the Netherlands indicates that the necessary condition was