Ideological congruence over government mandates under majoritarian and proportional representation electoral systems

The existing literature on ideological congruence has typically looked at congruence immediately after elections when governments are formed. This article goes beyond that comparative static approach by examining changes in citizen-government ideological congruence between two fixed points in time, namely at the beginning and end of government mandates. Building on a veto player approach and dynamics of party competition under majoritarian and proportional representation (PR) electoral systems, the results indicate, first, that government positions are more stable in between elections, as the number of parties and their ideological distance increase in cabinet. Second, it appears that single-party and homogeneous coalition governments decrease ideological congruence between elections under low levels of polarisation, while they increase congruence under very high levels of polarisation. Third, it was found that governments under majoritarian systems slightly decrease congruence between elections while congruence stays stable on average under PR systems. The different levels of party system polarisation across majoritarian and PR electoral systems mostly explain this difference.