Lobby index as a network centrality measure

We study the lobby index ( l -index for short) as a local node centrality measure for complex networks. The l -index is compared with degree (a local measure), betweenness and Eigenvector centralities (two global measures) in the case of a biological network (Yeast interaction protein–protein network) and a linguistic network (Moby Thesaurus II). In both networks, the l -index has a poor correlation with betweenness but correlates with degree and Eigenvector centralities. Although being local, the l -index carries more information about its neighbors than degree centrality. Also, it requires much less time to compute when compared with Eigenvector centrality. Results show that the l -index produces better results than degree and Eigenvector centrality for ranking purposes.