HITS algorithm
From Wikipedia, the free encyclopedia
Hyperlink-Induced Topic Search (HITS) is a link analysis algorithm that rates Web pages, developed by Jon Kleinberg. It determines two values for a page: its authority, which estimates the value of the content of the page, and its hub value, which estimates the value of its links to other pages.
Contents |
[edit] Algorithm details
Authority and hub values are defined in terms of one another in a mutual recursion. An authority value is computed as the sum of the scaled hub values that point to that page. A hub value is the sum of the scaled authority values of the pages it points to. Some implementations also consider the relevance of the linked pages.
HITS, like Page and Brin's PageRank, is an iterative algorithm based on the linkage of the documents on the web. However it does have some major differences:
- It is executed at query time, not at indexing time, with the associated hit on performance that accompanies query-time processing.
- It is not commonly used by search engines. (Though some sources claim a similar algorithm is used by Ask.com.)
- It computes two scores per document, hub and authority, as opposed to a single score.
- It is processed on a small subset of ‘relevant’ documents, not all documents as was the case with PageRank.
[edit] See also
[edit] References
- J. Kleinberg. Authoritative sources in a hyperlinked environment. In Proc. Ninth Ann. ACM-SIAM Symp. Discrete Algorithms, pages 668-677, ACM Press, New York, 1998.[1](PDF)
