Bill Slawski recently wrote an interesting post entitled Yahoo Replaces PageRank Assumptions with User Data. In the article, he discusses a "User Sensitive PageRank" patent application filed by Yahoo that addresses the flaws with PageRank. These flaws include the assumption that all links are created equal, bored surfers don't go to random pages, bored surfers don't always go to only trusted pages, pages change value at different rates, and sometimes PageRank calculations cheat.

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