They have investigated the properties of these text-based networks with the objective of understanding their structure and applying this knowledge to determine node importance/centrality, connectivity, growth and decay of interest, etc.
the ability to analyze networks, identify influential nodes, and discover hidden structures has led to important scientific and technological breakthroughs such as the discovery of communities of like-minded individuals (New-man and Girvan, 2004), the identification of influential people (Kempe et al., 2003), the ranking of scientists by their citation indexes (Radicchi et al., 2009), and the discovery of important scientific papers (Walker et al., 2006;Chen et al., 2007;Sayyadi and Getoor, 2009).