Balancing Authority and Diversity in Influential Node Mining
Diversity is a crucial criterion in many ranking and mining tasks. In this paper, we study how to incorporate node diversity into influence maximization (IM). We consider diversity as a reverse measure of the average similarity between selected nodes, which can be specified using node embedding or community detection results. Our goal is to identify a set of nodes which are simultaneously influential and diverse. Three most commonly used utilities in economics (i.e., Perfect Substitutes, Perfect Complements, and Cobb-Douglas) are proposed to jointly model influence spread and diversity as two factors. We formulate diversified IM as an optimization problem of these utilities, for which we present two approximation algorithms based on non-monotonic submodular maximization and traditional IM respectively. Experimental results show that our diversified IM framework outperforms other natural heuristics, such as embedding and diversified ranking, both in utility maximization and result diversification.