An exact almost optimal algorithm for target set selection in social networks

The Target Set Selection problem proposed by Kempe, Kleinberg, and Tardos, gives a nice clean combinatorial formulation for many problems arising in economy, sociology, and medicine. Its input is a graph with vertex thresholds, the social network, and the goal is find a subset of vertices, the target set, that “activates” a prespecified number of vertices in the graph. Activation of a vertex is defined via a so-called activation process as follows: Initially, all vertices in the target set become activate. Then at each step i of the process, each vertex get activated if the number of its neighbors active at iteration i − 1 exceeds its threshold. The activation process is “monotone” in the sense that once a vertex is activated, it remains active for the entire process. Unsurprisingly perhaps, Target Set Selection is NP-complete. More surprising is the fact that both of its maximization and minimization variants turn out to be extremely hard to approximate, even for very res...

• Type: Conference
• Year: 2009
• Where: SIGECOM
• Authors: Oren Ben-Zwi, Danny Hermelin, Daniel Lokshtanov, Ilan Newman
• Keywords: Activation Process, Information Management, SIGECOM 2009, Target Set, Target Set Selection