Search (2 results, page 1 of 1)

  • × author_ss:"Bar-Ilan, J."
  • × theme_ss:"Informetrie"
  1. Bar-Ilan, J.: On the overlap, the precision and estimated recall of search engines : a case study of the query 'Erdös' (1998) 0.04
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    Abstract
    Investigates the retrieval capabilities of 6 Internet search engines on a simple query. Existing work on search engine evaluation considers only the first 10 or 20 results returned by the search engine. In this work, all documents that the search engine pointed at were retrieved and thoroughly examined. Thus the precision of the whole retrieval process could be calculated, the overlap between the results of the engines studied, and an estimate on the recall of the searches given. The precision of the engines is high, recall is very low and the overlap is minimal
  2. Bar-Ilan, J.: ¬The Web as an information source on informetrics? : A content analysis (2000) 0.02
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    Abstract
    This article addresses the question of whether the Web can serve as an information source for research. Specifically, it analyzes by way of content analysis the Web pages retrieved by the major search engines on a particular date (June 7, 1998), as a result of the query 'informetrics OR informetric'. In 807 out of the 942 retrieved pages, the search terms were mentioned in the context of information science. Over 70% of the pages contained only indirect information on the topic, in the form of hypertext links and bibliographical references without annotation. The bibliographical references extracted from the Web pages were analyzed, and lists of most productive authors, most cited authors, works, and sources were compiled. The list of reference obtained from the Web was also compared to data retrieved from commercial databases. For most cases, the list of references extracted from the Web outperformed the commercial, bibliographic databases. The results of these comparisons indicate that valuable, freely available data is hidden in the Web waiting to be extracted from the millions of Web pages