A very nice application of social network analysis " When information about an underlying social network is available, seeding on the basis of this information, as typically captured by sociometric data, seems promising (Van den Bulte 2010). Such a strategy can distinguish three types of people: "hubs," who are well-connected people with a high number of connections to others; "fringes," who are poorly connected; and "bridges," who connect two oth- erwise unconnected parts of the network. The sociometric measure of degree centrality captures connectedness within the local environment (for details, see the Web Appendix at http://www.marketingpower.com/jmnov11 ), such that high- degree-centrality values characterize hubs, whereas low- degree-centrality values mark fringes. In contrast, the sociometric betweenness centrality measure describes the extent to which a person acts as a network intermediary, according to the share of shortest communication paths that pass through that person (see the Web Appendix). Thus, bridges earn high values on betweenness centrality measures." http://www.marketingpower.com/AboutAMA/Pages/AMA%20Publications/AMA%20Journals/Journal%20of%20Marketing/TOCs/SUM_2011.6/seeding_strategies_viral_marketing.aspx