Pacts with Twitter. Predicting voters' indecision and preferences for coalitions in multiparty systems

Abstract

In recent years, social networking sites (SNS) have become enormously popular, in particular microblogging sites such as Twitter. Twitter is nowadays one of the most used SNS for social, economic and political communication. Drawing on well-known characteristics of social networks and human behavior, i.e. the homophilic behavior of individuals, the power law distribution of influence and retweeting, and the nature of endorsement and the reduction of noise of retweeting, this article proposes a two-step method to first uncover the structure of the network of the top influential Twitter users in a political discussion and second based on the resulting structure of political clusters, predict the voters’ perception of the closeness between parties, the proportion of undecided voters between two given parties and the support for pacts between parties. The method analyzes the overlaps of communities of retweeters of the most influent users in a political conversation, and applies it to the Catalan elections in 2012. Comparing our results with those of the Spanish Center for Sociological Research, we show that the overlaps between parties' communities of retweeters are a good predictor of voters' indecision and preferences for post-electoral parliamentary support and coalitions.