Dynamics of Polarization and Coalition Formation in Signed Political Elite Networks

We study political elite networks within a framework of signed temporal network to investigate the dynamics of coalition formation and polarization during the 2014 Indonesian General Elections. We construct the signed network of inferred relations of agreement or disagreement between Indonesian political ac-tors based on their opinion that is reported by news media during the election. For each temporal network, we detect communities by applying a community detection algorithm for signed networks to identify conflicting groups of political ac-tors, and characterize the identified groups based on party attributes. We visualize the networks and measure political tensions within and between clusters to examine the dynamics of polarization over time. We find that the coalition pattern is absent during the legislative election period, where political actors are more likely to group within their respective party clusters. The intensity of polarization be-tween clusters is relatively lower than the following two periods, with a downward trend of polarization ahead of the legislative election day. The cleavage line between coalition clusters begins to form in the presidential election period and lasts into the post-election period, where the emerged pattern resembles the configuration of party coalitions in the 2014 Indonesian Presidential Election. The process of coalition formation is accompanied by an increase in the intensity of polarization between coalition clusters.