Shale Horowitz and Eric C. Browne, "Sources of Post-Communist Party System Consolidation: Ideology Versus Institutions," Party Politics, 11 (November, 2005), 689-706.

First Paragraph:
Particularly in new democracies, the number and relative strength of parties represented in the legislature is commonly viewed as a highly significant measure of political development. It is often argued, for example, that a large number of weak parties reflects political immaturity and, in any case, that it inhibits policy change and coherent policy outcomes. On the other hand, some argue that systems dominated by a single party, or even by two large parties, may do a poor job of representing the electorate, and in some cases verge on being undemocratic.1 Given such strong interests in the consequences of party system consolidation, we focus in this article on the prior question of causes - of what explains variation in party system consolidation.

Figures and Tables:
Figure 1. Ideological classification scheme for parties contesting elections in postcommunist democracies
Table 1. OLS models of party system consolidation (vote share concentration indices)

First Paragraph in Conclusion:
Models 1A and 3B examine the relative importance of ideological and institutional factors in the consolidation of party systems, while also controlling for population size. The models show that ideological consolidation appears to be a far more important influence on party system consolidation than institutional factors.