Multi-Party Competition: A Computational Model with Abstention and Biased Voters

Abstract

This paper analyses the properties of a computational model of multi-party competition in two and three policy dimensions. We present four substantive results: Firstly, centrifugal incentives prevent rational parties from moving to the mean of voters' preference distributions. Secondly, the number of parties competing for votes and the inclination to abstain from voting are positively related to parties' optimum distance to the political centre. Thirdly, the number of parties in the political arena also increases both the distance between parties' location in the policy space and the inter-temporal volatility of their platforms. Finally, assuming that voters rely on past observations of partisan positioning behaviour in order to assess the credibility of parties, this memory of a party's record is positively related to both the distances between partisan platforms and their deviation from the mean of voters' preferences but has a dampening effect for platform volatility.