Search (9 results, page 1 of 1)

  • × author_ss:"Walker, S."
  • × year_i:[1990 TO 2000}
  1. Robertson, S.E.; Walker, S.; Beaulieu, M.M.; Gatford, M.; Payne, A.: Okapi at TREC-4 (1996) 0.00
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    Type
    a
  2. Walker, S.: OCLC WorldCat collection sets (1998) 0.00
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  3. Robertson, S.E.; Walker, S.; Beaulieu, M.: Laboratory experiments with Okapi : participation in the TREC programme (1997) 0.00
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    Abstract
    Briefly reviews the history of laboratory testing of information retrieval systems, focusing on the idea of a general purpose test collection of documents, queries and relevance judgements. Gives an overview of the methods used in TREC (Text Retrieval Conference) which is concerned with an ideal test collection, and discusses the Okapi team's participation in TREC. Also discusses some of the issues surrounding the difficult problem of interactive evaluation in TREC. The reconciliation of the requirements of the laboratory context with the concerns of interactive retrieval has a long way to go
    Footnote
    Contribution to a thematic issue on Okapi and information retrieval research
    Type
    a
  4. Walker, S.: Views on classification as a search tool on a computer (1991) 0.00
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    Type
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  5. Hancock-Beaulieu, M.; Walker, S.: ¬An evaluation of automatic query expansion in an online library catalogue (1992) 0.00
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    Abstract
    An automatic query expansion (AQE) facility in anonline catalogue was evaluated in an operational library setting. The OKAPI experimental system had other features including: ranked output 'best match' keyword searching, automatic stemming, spelling normalisation and cross referencing as well as relevance feedback. A combination of transaction log analysis, search replays, questionnaires and interviews was used for data collection. Findings show that contrary to previous results, AQE was beneficial in a substantial number of searches. Use intentions, the effectiveness of the 'best match' search and user interaction were identified as the main factors affecting the take-up of the query expansion facility
    Type
    a
  6. Beaulieu, M.M.; Gatford, M.; Huang, X.; Robertson, S.E.; Walker, S.; Williams, P.: Okapi an TREC-5 (1997) 0.00
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    Type
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  7. Jones, S.; Gatford, M.; Robertson, S.; Hancock-Beaulieu, M.; Secker, J.; Walker, S.: Interactive thesaurus navigation : intelligence rules OK? (1995) 0.00
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    Abstract
    We discuss whether it is feasible to build intelligent rule- or weight-based algorithms into general-purpose software for interactive thesaurus navigation. We survey some approaches to the problem reported in the literature, particularly those involving the assignement of 'link weights' in a thesaurus network, and point out some problems of both principle and practice. We then describe investigations which entailed logging the behavior of thesaurus users and testing the effect of thesaurus-based query enhancement in an IR system using term weighting, in an attempt to identify successful strategies to incorporate into automatic procedures. The results cause us to question many of the assumptions made by previous researchers in this area
    Type
    a
  8. Robertson, S.E.; Walker, S.; Hancock-Beaulieu, M.M.: Large test collection experiments of an operational, interactive system : OKAPI at TREC (1995) 0.00
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    Abstract
    The Okapi system has been used in a series of experiments on the TREC collections, investiganting probabilistic methods, relevance feedback, and query expansion, and interaction issues. Some new probabilistic models have been developed, resulting in simple weigthing functions that take account of document length and within document and within query term frequency. All have been shown to be beneficial when based on large quantities of relevance data as in the routing task. Interaction issues are much more difficult to evaluate in the TREC framework, and no benefits have yet been demonstrated from feedback based on small numbers of 'relevant' items identified by intermediary searchers
    Type
    a
  9. Walker, S.: Subject access in online catalogues (1991) 0.00
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    Type
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