Fluctuations in Document Accessibility: A Case Study of Five Search Engines
http://journals.syne.org/pub/index.php?journal=IJTC&page=article&op=view&path[]=31
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Shafi, S.M. and Rafiq Ahmad Rather
International Journal for Technical Communication
2006

Abstract:

This paper presents an empirical investigation of the stability of five search engines, namely Altavista, Google, Hotbot, Scirus and Bioweb, carried out over two different time periods with different search queries selected from 'LC List of Subject Headings' with a closer examination of the URLs and their contents. The three different fluctuations identified, one of them being significant, show that Hotbot is prone to result fluctuations while Scirus is inclined to indexing fluctuations, and Bioweb is the most stable.