Ranking models to identify influential actors in large-scale social networks

Abstract

In this thesis, we develop a framework to identify prominent actors from several perspectives. We first investigate the importance of actors in actor-actor networks. In these networks, centrality algorithms are good candidates. However, these centrality measures suffer from several issues - they either look solely at the structure of the network disregarding issues like attention nodes have to give to others or make a shortest path interaction assumption that might be impractical in large networks. To address these issues, we develop two algorithms "Attentive Betweenness Centrality (ABC)" and "Attentive Closeness Centrality (ACC)". These two algorithms take multiple paths of information flow and attention into consideration while computing importance scores of actors. ABC reduces anomalous behaviors of classical betweenness centrality while captures its essence. ACC, on the other hand, targets the improvement of closeness. These two algorithms have high performance in identifying prominent actors.