A webgraph is a set of directed links between pages of the World Wide Web. A graph, in general, consists of several vertices, some pairs connected by edges. In a directed graph, edges are directed lines or arcs. The webgraph is a directed graph, whose vertices correspond to the pages of the WWW, and a directed edge connects page X to page Y if there exists a hyperlink on page X, referring to page Y.
Properties
The degree distribution of the webgraph strongly differs from the degree distribution of the classical random graph model, the Erdős–Rényi model: in the Erdős–Rényi model, there are very few large degree nodes, relative to the webgraph's degree distribution. The precise distribution is unclear, however: it is relatively well described by a lognormal distribution, as well as the Barabási–Albert model for power laws.. The webgraph is an example of a scale-free network.
Applications
The webgraph is used for: computing the PageRank of the world wide web's pages; computing the personalized PageRank;Glen Jeh and Jennifer Widom. 2003. Scaling personalized web search. In Proceedings of the 12th international conference on World Wide Web (WWW '03). ACM, New York, NY, USA, 271–279. detecting webpages of similar topics, through graph-theoretical properties only, like co-citation; and identifying hubs and authorities in the web for HITS algorithm.
References
External links Webgraphs in Yahoo Sandbox Webgraphs at University of Milano – Laboratory for Web Algorithmics Webgraphs at Stanford – SNAP
Web Data Commons - Hyperlink Graph