PageRank is an interesting alogorithm developed by Google's founders LarryPage and SergeyBrin at Stanford University. Using the hyperlink structure information of the Web, it computes an authority value for each Web page, which can be later used to improve the ranking process. The authority value of a Web page is based on the authority values of the Web pages linking to it. Google claims that PageRank continues to be the basis of its ranking mechanism; http://www.google.com/technology/
The AbsorbingModel; http://ir.dcs.gla.ac.uk/terrier/publications.html developed within the Terrier project, takes a different approach and proposes a new model for hyperlink analysis, which can be used in either a query-independent, or a query-dependent way.