Political social-learning: short-term memory and cycles of polarization

This paper investigates the effect of voters' short-term memory on political outcomes by considering politics as a collective learning process. We find that short-term memory may lead to cycles of polarisation and consensus across parties' platforms. Following periods of party consensus, short-term memory implies that there is little variation in voters' data and therefore limited information about the true state of the world. This in turn allows parties to further their own interests and hence polarise by offering different policies. In contrast, periods of polarisation and turnover involve sufficient variation in the data that allows voters to be confident about what the correct policy is, forcing both parties to offer this policy.