sobre grafos sociales para hacer análisis de las redes sociales (Social network analysis)
NodeXL is an Excel 2007 template for viewing and analyzing network graphs, along with a set of .NET Framework 3.5 class libraries that can be used to add network graphs to custom applications. NodeXL used to be called ".NetMap".
A network graph is a series of vertices (sometimes called nodes) connected by edges. See this Wikipedia article for an overview of network graphs.
Muy interesantes infografías sobre Medios Sociales