Search (3 results, page 1 of 1)

  • × author_ss:"Robertson, A.M."
  • × author_ss:"Willett, P."
  • × year_i:[1990 TO 2000}
  1. Ekmekcioglu, F.C.; Robertson, A.M.; Willett, P.: Effectiveness of query expansion in ranked-output document retrieval systems (1992) 0.01 
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    Abstract
    Reports an evaluation of 3 methods for the expansion of natural language queries in ranked output retrieval systems. The methods are based on term co-occurrence data, on Soundex codes, and on a string similarity measure. Searches for 110 queries in a data base of 26.280 titles and abstracts suggest that there is no significant difference in retrieval effectiveness between any of these methods and unexpanded searches
  2. Robertson, A.M.; Willett, P.: Identification of word-variants in historical text databases : report for the period October 1990 to September 1992 (1994) 0.01 
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    Abstract
    Databases of historical texts are increasingly becoming available for end user searching via online or CD-ROM databases. Many of the words in these databases are spelt differently from today with resultant loss of retrieval. The project evaluated a range of techniques that can suggest historical variants of modern language query words, the work deriving from earlier work on spelling correction
  3. Robertson, A.M.; Willett, P.: Use of genetic algorithms in information retrieval (1995) 0.01 
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    Abstract
    Reviews the basic techniques involving genetic algorithms and their application to 2 problems in information retrieval: the generation of equifrequent groups of index terms; and the identification of optimal query and term weights. The algorithm developed for the generation of equifrequent groupings proved to be effective in operation, achieving results comparable with those obtained using a good deterministic algorithm. The algorithm developed for the identification of optimal query and term weighting involves fitness function that is based on full relevance information

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