Group Centrality for Semantic Networks: a SWOT analysis featuring Random   Walks
  Group centrality is an extension of the classical notion of centrality for individuals, to make it applicable to sets of them. We perform a SWOT (strengths, weaknesses, opportunities and threats) analysis of the use of group centrality in semantic networks, for different centrality notions: degree, closeness, betweenness, giving prominence to random walks. Among our main results stand out the relevance and NP-hardness of the problem of finding the most central set in a semantic network for an specific centrality measure. 
Camilo Garrido, Ricardo Mora and Claudio Gutierrez
cs.SI