Search (2 results, page 1 of 1)

  • × author_ss:"Willett, P."
  • × theme_ss:"Semantisches Umfeld in Indexierung u. Retrieval"
  1. Robertson, A.M.; Willett, P.: Applications of n-grams in textual information systems (1998) 0.05 
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    Abstract
    Provides an introduction to the use of n-grams in textual information systems, where an n-gram is a string of n, usually adjacent, characters, extracted from a section of continuous text. Applications that can be implemented efficiently and effectively using sets of n-grams include spelling errors detection and correction, query expansion, information retrieval with serial, inverted and signature files, dictionary look up, text compression, and language identification
    Source
    Journal of documentation. 54(1998) no.1, S.48-69
  2. 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
    Source
    Journal of information science. 18(1992) no.2, S.139-147

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