Search (2 results, page 1 of 1)

  • × author_ss:"Robertson, S.E."
  • × theme_ss:"Semantisches Umfeld in Indexierung u. Retrieval"
  1. Robertson, S.E.: On relevance weight estimation and query expansion (1986) 0.02
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    Abstract
    A Bayesian argument is used to suggest modifications to the Robertson/Sparck Jones relevance weighting formula, to accomodate the addition to the query of terms taken from the relevant documents identified during the search
  2. Robertson, S.E.: OKAPI at TREC-3 (1995) 0.02
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    Abstract
    Reports text information retrieval experiments performed as part of the 3 rd round of Text Retrieval Conferences (TREC) using the Okapi online catalogue system at City University, UK. The emphasis in TREC-3 was: further refinement of term weighting functions; an investigation of run time passage determination and searching; expansion of ad hoc queries by terms extracted from the top documents retrieved by a trial search; new methods for choosing query expansion terms after relevance feedback, now split into methods of ranking terms prior to selection and subsequent selection procedures; and the development of a user interface procedure within the new TREC interactive search framework