Patent ID: 7640488

Claim:
A method of performing a focused random walk to produce a plurality of samples on a topic from a collection of hyper-linked pages, comprising: setting a current page to a user-specified page; repeatedly executing the following steps until an exit criteria is met: accepting the current page as a sample if it is classified as on topic; obtaining a plurality of in-links to the page; extracting a plurality of out-links from the page; selecting a random link from a union of the in-links and the out-links of the page; analyzing the random link according to a predetermined method; accepting the random link if the random link meets predetermined criteria, and setting the page linked by the random link as a current page; determining if the page linked by the random link which has been set to the current page has been previously visited; and keeping the in-links and the out-links stored in a traversal history table and associated with the current page unchanged, in response to determining that the page linked by the random walk link has been previously visited.