This is p. 180
1. Fractionalization, i.e., the variation in the number and strength of the constituent parts of the party systems
Lane and Ersson also concluded that the basic problem for the study party system is the analysis of change on these dimensions, which they defined as both fluctuations and trends.
In recent years, measurement of party system change has been one of the most important research topics in comparative politics (Mair 1983; Flannigan and Dalton 1984; Wolinetz 1988; Laver 1989, Mair 1989b, Smith 1989, Smith and Mair 1989, Smith and Mair 1990). Fewer writings, however, have tried to explain system change (Silverman 1985, Mair 1989a, Alber 1989, Carmines 1991). Those that have, as Reiter said, consider rising "affluence, the growth of the state, ... neo-corporatism, the mass media, new political issues and cleavages, problems with state performance, or post-industrialism" (1989, 329). Inglehart's work on postindustrialism (1990) and a new politics stressing the environment and quality of life is heavily featured in this literature. Poguntke (1987) for example, spelled out central elements of the new politics and suggested five possible effects on party systems: formation of new social movements, take-over of small parties, splitting of larger left-wing party into a post-material left party, alienation of new politics citizens and withdrawal of political support, and foundation of a new party (pp.78-79). Party system concepts have figured most prominently as independent variables in cross-sectional analyses of political system performance. Powell's analysis of 28 party systems in the 1965-75 period found that those high in support for extremist parties had executive instability and mass rioting (1981). In a later study, he distinguished between effects on instability and those on rioting (1986). However, Lane and Ersson (1987a) found only indirect effects of party system fractionalization and polarization on social disorder and government instability.
The most developed theory about party systems is that on electoral systems, which usually treats party systems as dependent variables. Much of this theory originated in Book II of Duverger, and the proposition that single-member districts and plurality elections produce a two-party system has become known as "Duverger's Law" (Taagepera and Grofman 1985, Scarrow 1986). Fortunately, that vast literature has been admirably represented in some recent publications (Grofman and Lijphart 1986, Lijphart 1990). Blais (1991) also produced an excellent summary of the "debate" over electoral systems, complete with explanatory models of electoral effects. Reviewing the evidence on proportional representation, Blais says, "PR is not clearly superior to the plurality rule in promoting political order in advanced democracies and seems to be a risky choice in new ones" (p. 246).
With the fall of communism and the emergence of party competition in Eastern Europe, the effects of electoral systems on party party politics assumed new political importance. Lijphart soon became the most prominent advocate of PR and multiparty politics for these emergent nations, arguing that PR and parliamentary government had a better record than alternative plurality systems, "particularly with respect to representation, protection of minority interests, voter participation, and control of unemployment" (1991a, 83). In reply, Quade defended plurality systems and criticized Lijphart's argument:
Plurality voting encourages the competing parties to adopt a majority-forming attitude. The parties incline to be moderate, to seek conciliation, to round off their rough edges--in short, to do before the election, in the public view, the very tasks that Lijphart applauds PR systems for doing after the election" (1991, 41).
Laryedret sided with Quade, saying, "Parties in plurality systems tend to be moderate because most votes are to be gained among the undecided voters of the center" (1991, 33). In his rejoinder, Lijphart (1991b) held that democracies often turned to PR to accommodate cleavages, that the superior economic record of PR systems was unquestioned, and that plurality systems produced distorted majorities that were seen as undemocratic.
In the midst of this academic debate, the new nations devised new electoral systems. Hibbing and Patterson (1992) described Hungary's complex system involving PR and plurality voting, and they favored its plurality features over straight PR. Analyzing the Polish situation, Jasiewicz (1992) found less fault with the electoral system than with its lack of established parties, although he was not convinced by Lijphart's case for PR. Later, Lijphart (1992) analyzed the choice of voting systems in Czecho-Slovakia, Hungary, and Poland during the collapse of communism, testing Stein Rokkan's hypothesis that old established bourgeois parties in the late 1800s (and communist parties in the late 1980s) favored PR as a way of retaining some power against