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  • × theme_ss:"OPAC"
  • × theme_ss:"Retrievalalgorithmen"
  1. Khoo, C.S.G.; Wan, K.-W.: ¬A simple relevancy-ranking strategy for an interface to Boolean OPACs (2004) 0.02 
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    Abstract
    A relevancy-ranking algorithm for a natural language interface to Boolean online public access catalogs (OPACs) was formulated and compared with that currently used in a knowledge-based search interface called the E-Referencer, being developed by the authors. The algorithm makes use of seven weIl-known ranking criteria: breadth of match, section weighting, proximity of query words, variant word forms (stemming), document frequency, term frequency and document length. The algorithm converts a natural language query into a series of increasingly broader Boolean search statements. In a small experiment with ten subjects in which the algorithm was simulated by hand, the algorithm obtained good results with a mean overall precision of 0.42 and mean average precision of 0.62, representing a 27 percent improvement in precision and 41 percent improvement in average precision compared to the E-Referencer. The usefulness of each step in the algorithm was analyzed and suggestions are made for improving the algorithm.
    Source
    Electronic library. 22(2004) no.2, S.112-120
  2. Koopman, R.: ¬Ein OPAC mit Gewichtungsalgorithmen : Der PICA Micro OPC (1996) 0.02 
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    Source
    Zukunft der Sacherschließung im OPAC: Vorträge des 2. Düsseldorfer OPAC-Kolloquiums am 21. Juni 1995. Hrsg.: E. Niggemann u. K. Lepsky
  3. Hancock-Beaulieu, M.; Walker, S.: ¬An evaluation of automatic query expansion in an online library catalogue (1992) 0.01 
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    Theme
    Semantisches Umfeld in Indexierung u. Retrieval
  4. Beaulieu, M.; Jones, S.: Interactive searching and interface issues in the Okapi best match probabilistic retrieval system (1998) 0.01 
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    Theme
    Semantisches Umfeld in Indexierung u. Retrieval

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