Search (6 results, page 1 of 1)

  • × year_i:[1990 TO 2000}
  • × author_ss:"Robertson, S.E."
  1. Robertson, S.E.; Hancock-Beaulieu, M.M.: On the evaluation of IR systems (1992) 0.02
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  2. MacFarlane, A.; Robertson, S.E.; McCann, J.A.: Parallel computing in information retrieval : an updated review (1997) 0.02
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    Abstract
    Reviews the progress of parallel computing in information retrieval. Stresses the importance of the motivation is using parallel computing for text retrieval. Analyzes parallel IR systems using a classification defined by Rasmussen and describes some parallel IR systems. Gives a description of the retrieval models used in parallel information processing and notes areas where research is needed
  3. Robertson, S.E.: Overview of the Okapi projects (1997) 0.02
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    Abstract
    Gives a brief description of the Okapi projects and of the work of the centre for Interactive Systems Research in the Department of Information Science at City University, London,UK, where these projects have been developed. Describes firstly one version of an information retrieval system which contains some of the central features of the Okapi projects, and follows this with an indication of the variety of systems now implemented or implementable within the present setup
  4. Robertson, S.E.; Beaulieu, M.: Research and evaluation in information retrieval (1997) 0.01
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    Abstract
    Offered as a discussion document drawing on the experiences of the Okapi team in developing information retrieval systems. Raises some of the issues currently exercising the information retrieval community in the context of experimentation and evaluation
  5. Robertson, S.E.; Walker, S.; Beaulieu, M.: Laboratory experiments with Okapi : participation in the TREC programme (1997) 0.01
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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
  6. Robertson, S.E.; Sparck Jones, K.: Simple, proven approaches to text retrieval (1997) 0.01
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    Abstract
    This technical note describes straightforward techniques for document indexing and retrieval that have been solidly established through extensive testing and are easy to apply. They are useful for many different types of text material, are viable for very large files, and have the advantage that they do not require special skills or training for searching, but are easy for end users. The document and text retrieval methods described here have a sound theoretical basis, are well established by extensive testing, and the ideas involved are now implemented in some commercial retrieval systems. Testing in the last few years has, in particular, shown that the methods presented here work very well with full texts, not only title and abstracts, and with large files of texts containing three quarters of a million documents. These tests, the TREC Tests (see Harman 1993 - 1997; IP&M 1995), have been rigorous comparative evaluations involving many different approaches to information retrieval. These techniques depend an the use of simple terms for indexing both request and document texts; an term weighting exploiting statistical information about term occurrences; an scoring for request-document matching, using these weights, to obtain a ranked search output; and an relevance feedback to modify request weights or term sets in iterative searching. The normal implementation is via an inverted file organisation using a term list with linked document identifiers, plus counting data, and pointers to the actual texts. The user's request can be a word list, phrases, sentences or extended text.