Multi-party competition: A computational model with abstention and memory

This paper analyses the properties of a computational model of multi-party competition in two policy dimensions. We find that, 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 volatility of their platforms. Finally, the more voters rely on past observations of partisan positioning behaviour in order to assess the credibility of parties, the more the distance between partisan platforms increases. At the same time, platform volatility declines.