THE SPATIAL MODEL WITH ACTIVISTS

As our discussion of Israel in Chapter 4 illustrated, government in multiparty polities, based on proportional electoral methods, requires the cooperation of several parties. The model of coalition bargaining indicates that a large, centrally located party, at a core position, will be dominant. Such a core party can, if it chooses, form a minority government by itself and control policy outcomes. If party leaders are aware of the fact that they can control policy from the core, then this centripetal tendency should lead parties to position themselves at the center.

Yet, contrary to this intuition there is ample empirical evidence that party leaders or political contenders do not necessarily adopt centrist positions. For example, Budge et al. (1987) and Laver and Budge (1992), in their study of European party manifestos, found no evidence of a strong centripetal tendency. The electoral models for Israel and Italy presented in the previous two chapters estimated party positions in various ways, and concluded that there is no indication of policy convergence by parties. Theorem 3.1 indicates why convergence does not occur in these two polities. In this chapter, we re-examine the earlier empirical analyses for the Netherlands (Schofield et al., 1998; Quinn, Martin, and Whitford, 1999; Quinn and Martin, 2002) to determine if the nonconvergence noted previously can be accounted for by the electoral theorem.