Search (1 results, page 1 of 1)

0.013754521 = product of:
  0.027509041 = sum of:
    0.027509041 = product of:
      0.055018082 = sum of:
        0.055018082 = weight(_text_:t in 5169) [ClassicSimilarity], result of:
          0.055018082 = score(doc=5169,freq=4.0), product of:
            0.17876579 = queryWeight, product of:
              3.9394085 = idf(docFreq=2338, maxDocs=44218)
              0.04537884 = queryNorm
            0.3077663 = fieldWeight in 5169, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              3.9394085 = idf(docFreq=2338, maxDocs=44218)
              0.0390625 = fieldNorm(doc=5169)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Abstract

Ruthven, Mounia, and van Rijsbergen rank and select terms for query expansion using information gathered on searcher evaluation behavior. Using the TREC Financial Times and Los Angeles Times collections and search topics from TREC-6 placed in simulated work situations, six student subjects each preformed three searches on an experimental system and three on a control system with instructions to search by natural language expression in any way they found comfortable. Searching was analyzed for behavior differences between experimental and control situations, and for effectiveness and perceptions. In three experiments paired t-tests were the analysis tool with controls being a no relevance feedback system, a standard ranking for automatic expansion system, and a standard ranking for interactive expansion while the experimental systems based ranking upon user information on temporal relevance and partial relevance. Two further experiments compare using user behavior (number assessed relevant and similarity of relevant documents) to choose a query expansion technique against a non-selective technique and finally the effect of providing the user with knowledge of the process. When partial relevance data and time of assessment data are incorporated in term ranking more relevant documents were recovered in fewer iterations, however retrieval effectiveness overall was not improved. The subjects, none-the-less, rated the suggested terms as more useful and used them more heavily. Explanations of what the feedback techniques were doing led to higher use of the techniques.