document: Ranking the web frontier The celebrated PageRank algorithm has proved to be a very effective paradigm for ranking results of web search algorithms . In this paper we refine this basic paradigm to take into account several evolving prominent features of the web , and propose several algorithmic innovations . First , we analyze features of the rapidly growing `` frontier '' of the web , namely the part of the web that crawlers are unable to cover for one reason or another . We analyze the effect of these pages and find it to be significant . We suggest ways to improve the quality of ranking by modeling the growing presence of `` link rot '' on the web as more sites and pages fall out of maintenance . Finally we suggest new methods of ranking that are motivated by the hierarchical structure of the web , are more efficient than PageRank , and may be more resistant to direct manipulation .
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