On the other hand, Web is a hypertext environment, and hyperlink analysis has been widely used in the Web information processing system, such as Google (Sergey Brin 1998) and HITS (Jon M. Kleinberg 1999).
these systems just regard the hyperlink as the simple reference and endorsement, actually from the point view of the author of the Web page, the hyperlink tells the diverse inter-page semantic information of Web pages, such as reference, related topic and document organizing structure, etc.