Rekha Diwakar, "Party Aggregation in India: A State Level Analysis," Party Politics, 16 (July, 2010), 477-496. [Available at http://ppq.sagepub.com/content/vol16/issue4/ ]

First paragraph:
Most accounts of party systems assume that factors affecting the district level party system also affect the national party system in an almost axiomatic way. This assumption has led to comparative studies focusing on the national level and testing the determinants of the size of party systems. Recently, however, scholars have pointed out that formation of a national party system involves coordination by voters and parties across a country's districts and states, and therefore the national party system is affected by the strength of the 'aggregation' or 'linkage' between the national and district level party systems. Jones and Mainwaring (2003: 140) point out that a party system is 'highly nationalized (aggregated) . . . [when] the major parties' respective vote shares do not differ much from one province to the next. In weakly nationalized systems, the major parties' vote-shares vary widely across provinces'. Chhibber and Kollman (1998, 2004) use the term 'aggregation', while Cox (1997) uses 'linkage' to describe the relationship between party systems at district and national levels.1 Chhibber and Kollman (2004: 4) define 'national party system as one in which the same parties compete at different levels of vote aggregation' and point out that:

Regardless of electoral rules, politicians have always seen it in their collective and individual interests to establish linkage across district lines, to aggregate their votes across districts to create regional or national parties that can influence policy or run the government. We call this process party aggregation. (p. 19)

The party aggregation phenomenon is an important change in the party system over time, and one that has consequences. Persson and Tabellini (2003) refer to the effects of nationalization of party system on introducing policy change, while Sartori (1976) and Chhibber and Kollman (2004) support the view that having a nationalized, as opposed to a fragmented, party system helps in focusing the efforts of voters and parties into a smaller number of coalitions and in forcing governments to address important national level problems. Similarly, Schattschneider ([1960]1975) holds the view that parties organized at the national level represent the most important force by which to counter the interests and power of the wealthy in modern democracies. Whether or not national parties are more desirable than regional parties, the causes and consequences of the process of aggregation which help parties to link across districts and states have important consequences and therefore represent an important area of research for scholars.

Figures and Tables:

Table 1. Effective number of parties in Indian national elections

Figure 1. Average ENP in India at national, state and district levels by election.

Figure 2. Effect of federal centralization and states' dependence on party aggregation

Figure 3. Effective number of parties (ENP) and party aggregation trends at state level in India

Figure 4. ENP at state level in highly dependent and other states in India

Table 2. Regression results

Last Paragraph:
(first paragraph of conclusion) In this article I have shown that party aggregation shapes the formation not only of national but also of state level party systems, and argue that we need to extend our study of this phenomenon at the sub-national level. Using evidence from Indian states, I cannot find unequivocal support for the federal centralization argument put forward by existing scholars, which is to explain changes in party aggregation at the national level. Thus, while federal centralization leads to a decrease in the number of parties and higher aggregation in the Indian states, the effects of federal decentralization are not uniform and significant. My findings suggest a need to incorporate a more comprehensive set of explanatory variables in the study of party aggregation. In the Indian context, I highlight the dependence of states on national government as one such factor, and find that party aggregation in the highly dependent states more closely follows the changes in federal distribution of powers than is witnessed in other states.