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Compute Google's PageRank 5 Times Faster

Posted by timothy on from the hypercustom dept.

Kimberley Burchett writes "CS researchers at Stanford University have developed three new techniques that together could speed up Google's PageRank calculations by a factor of five. An article at ScienceBlog theorizes that "The speed-ups to Google's method may make it realistic to calculate page rankings personalized for an individual's interests or customized to a particular topic.""

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  1. CmdrTaco, ScienceBlog editor? by jbellis · · Score: 5, Interesting
    A 5 times speedup is still many orders of magnitude too slow to personalize terabytes of data for millions of customers. That's just ludicrous. But somehow Science Blog puts "...may make it realistic to calculate page rankings personalized for an individual's interests" in their abstract when the actual article from National Science Foundation says nothing of the sort:
    Computing PageRank, the ranking algorithm behind the Google search engine, for a billion Web pages can take several days. Google currently ranks and searches 3 billion Web pages. Each personalized or topic-sensitive ranking would require a separate multi-day computation, but the payoff would be less time spent wading through irrelevant search results. For example, searching a sports-specific Google site for "Giants" would give more importance to pages about the New York or San Francisco Giants and less importance to pages about Jack and the Beanstalk.
    ...
    The complexities of a personalized ranking would require [far] greater speed-ups to the PageRank calculations. In addition, while a faster algorithm shortens computation time, the issue of storage remains. Because the results from a single PageRank computation on a few billion Web pages require several gigabytes of storage, saving a personalized PageRank for many individuals would rapidly consume vast amounts of storage. Saving a limited number of topic-specific PageRank calculations would be more practical.
    Clearly the ScienceBlog and /. editors share more than a work ethic, or, uh, lack thereof. Next up: CmdrTaco's secret double life revealed!