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  • × author_ss:"Walker, S."
  1. Walker, S.: ¬The Okapi online catalogue research projects (1989) 0.01
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    Date
    16. 8.1998 11:22:08
    Footnote
    Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.424-435.
  2. Walker, S.: Improving subject access painlessly : recent work on the Okapi online catalogue projects (1988) 0.01
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    Source
    Program. 22(1988), S.21-31
  3. Walker, S.; DeVere, R.: Improving subject retrieval in online catalogues : T.2: Relevance feedback and query expansion (1990) 0.01
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    Content
    1. Introduction // 2. Query modification through relevance feedback // 3. System design & description 4. Evaluation // 5. Analysis & results // 6. Conclusions and recommendations
    Theme
    Semantisches Umfeld in Indexierung u. Retrieval
  4. 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
    Theme
    Semantisches Umfeld in Indexierung u. Retrieval
  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
    Theme
    Semantisches Umfeld in Indexierung u. Retrieval
  6. Walker, S.; Jones, R.M.: Improving subject retrieval in online catalogues : T.1: Stemming, automatic spelling correction and cross-reference tables (1987) 0.00
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    Theme
    Verbale Doksprachen im Online-Retrieval
  7. Mitev, N.N.; Walker, S.: Information retrieval aids in an online public access catalogue : automatic intelligent search sequencing (1985) 0.00
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    Source
    Advances in intelligent retrieval: Proc. of a Conf. ... Wadham College, Oxford, 16.-17.4.1985. Intr.: M. Rowbottom
  8. Robertson, S.E.; Walker, S.: Some simple effective approximations to the 2-Poisson molde for probabilisitc weighted retrieval (1979) 0.00
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    Footnote
    Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.345-453.
  9. 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
  10. Sparck Jones, K.; Walker, S.; Robertson, S.E.: ¬A probabilistic model of information retrieval : development and comparative experiments - part 1 (2000) 0.00
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  11. Sparck Jones, K.; Walker, S.; Robertson, S.E.: ¬A probabilistic model of information retrieval : development and comparative experiments - part 2 (2000) 0.00
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  12. Robertson, S.E.; Walker, S.; Beaulieu, M.M.; Gatford, M.; Payne, A.: Okapi at TREC-4 (1996) 0.00
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    Source
    The Fourth Text Retrieval Conference (TREC-4). Ed.: K. Harman
  13. 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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    Source
    The Fifth Text Retrieval Conference (TREC-5). Ed.: E.M. Voorhees u. D.K. Harman
  14. Walker, S.: Subject access in online catalogues (1991) 0.00
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    Abstract
    Discusses some of the methods of subject access to on-line catalohues (OPACs) and argues that none are entirley satisfactory. Describes 2 methods for improving subject access: best match searching; and automatic query expansion application and discusses their feasibility. Mentions emerging application standards for information retrieval and concludes that existing standards are incompatible with most methods for improving standards
    Theme
    Semantisches Umfeld in Indexierung u. Retrieval
  15. Walker, S.: Views on classification as a search tool on a computer (1991) 0.00
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    Abstract
    Classification numbers and shelf marks may be useful in online searching. Ways of using classification in online searching include: direct classification searching; use of classification as linking devices or pivots; and direct or indirect searching of classification schedules and indexes. Discusses each of these techniques, mainly in the context of library OPAC searching although they may be applied to other types of online retrieval systems. The use of classification numbers as pivots enabling online searchers to retrieve related references by means of automation searching of identical or related classification numbers is reviewed with reference to the OKAPI project; BLCMP project and the DDC online project
    Theme
    Klassifikationssysteme im Online-Retrieval
  16. 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