We develop and test an equilibrium model of party structure to account for the large and ever-changing number of political parties that contest Indian state elections. The analysis finds that the number of parties increases with the voting density of state constituencies, the heterogeneity of the state’s electorate, state per capita income and literacy levels, falls with average age while responding to a set of constitutional and legislative rules designed to affect party and electoral performance. The model is also applied to entry and exit, allowing the empirics to highlight those factors that affect party turnover rather than aggregate party numbers. The model explains better the number of parties than ENP, the effective (vote share weighted) number of parties, implying that the variability in the fringe of smaller parties has not substantially affected the vote shares received by the larger more established parties. Affirmative action, primarily in the form of increases in the proportion of seats reserved for members of special castes is associated with a reduction in both party numbers and ENP consistent with speeding the integration of scheduled castes into broader based political parties.

我们开发并测试了一个政党结构的均衡模型，以解释参与印度州选举的大量且不断变化的政党。分析发现，政党的数量随着州选区的投票密度、州选民的异质性、州人均收入和识字水平的增加而增加，随着平均年龄的下降而下降，同时对旨在影响政党的一系列宪法和立法规则作出反应和选举表现。该模型也适用于进入和退出，允许经验突出那些影响政党流动的因素，而不是党的总数。该模型比 ENP 更好地解释了政党的数量，即有效的（投票份额加权）政党数量，这意味着较小政党边缘的可变性并未对较大的较成熟政党获得的投票份额产生实质性影响。平权行动，主要是增加为特殊种姓成员保留的席位比例的形式，与政党人数和 ENP 的减少有关，这与加速将在册种姓融入更广泛的政党相一致。