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  • × author_ss:"Järvelin, K."
  • × theme_ss:"Klassifikationssysteme im Online-Retrieval"
  1. Järvelin, K.; Niemi, T.: Deductive information retrieval based on classifications (1993) 0.00
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    Abstract
    Modern fact databses contain abundant data classified through several classifications. Typically, users msut consult these classifications in separate manuals or files, thus making their effective use difficult. Contemporary database systems do little support deductive use of classifications. In this study we show how deductive data management techniques can be applied to the utilization of data value classifications. Computation of transitive class relationships is of primary importance here. We define a representation of classifications which supports transitive computation and present an operation-oriented deductive query language tailored for classification-based deductive information retrieval. The operations of this language are on the same abstraction level as relational algebra operations and can be integrated with these to form a powerful and flexible query language for deductive information retrieval. We define the integration of these operations and demonstrate the usefulness of the language in terms of several sample queries
    Source
    Journal of the American Society for Information Science. 44(1993) no.10, S.557-578