Search (44 results, page 3 of 3)

  • × theme_ss:"Retrievalstudien"
  • × type_ss:"a"
  • × year_i:[1980 TO 1990}
  1. MacCain, K.W.; White, H.D.; Griffith, B.C.: Comparing retrieval performance in online data bases (1987) 0.00
    0.0015199365 = product of:
      0.003039873 = sum of:
        0.003039873 = product of:
          0.006079746 = sum of:
            0.006079746 = weight(_text_:a in 1167) [ClassicSimilarity], result of:
              0.006079746 = score(doc=1167,freq=8.0), product of:
                0.04772363 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.041389145 = queryNorm
                0.12739488 = fieldWeight in 1167, product of:
                  2.828427 = tf(freq=8.0), with freq of:
                    8.0 = termFreq=8.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=1167)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    This study systematically compares retrievals on 11 topics across five well-known data bases, with MEDLINE's subject indexing as a focus. Each topic was posed by a researcher in the medical behavioral sciences. Each was searches in MEDLINE, EXCERPTA MEDICA, and PSYCHINFO, which permit descriptor searches, and in SCISEARCH and SOCIAL SCISEARCH, which express topics through cited references. Searches on each topic were made with (1) descriptors, (2) cited references, and (3) natural language (a capabiblity common to all five data bases). The researchers who posed the topics judged the results. In every case, the set of records judged relevant was used to to calculate recall, precision, and novelty ratios. Overall, MEDLINE had the highest recall percentage (37%), followed by SSCI (31%). All searches resulted in high precision ratios; novelty ratios of data bases and searches varied widely. Differences in record format among data bases affected the success of the natural language retrievals. Some 445 documents judged relevant were not retrieved from MEDLINE using its descriptors; they were found in MEDLINE through natural language or in an alternative data base. An analysis was performed to examine possible faults in MEDLINE subject indexing as the reason for their nonretrieval. However, no patterns of indexing failure could be seen in those documents subsequently found in MEDLINE through known-item searches. Documents not found in MEDLINE primarily represent failures of coverage - articles were from nonindexed or selectively indexed journals
    Type
    a
  2. Salton, G.: Thoughts about modern retrieval technologies (1988) 0.00
    0.0015046606 = product of:
      0.0030093212 = sum of:
        0.0030093212 = product of:
          0.0060186423 = sum of:
            0.0060186423 = weight(_text_:a in 1522) [ClassicSimilarity], result of:
              0.0060186423 = score(doc=1522,freq=4.0), product of:
                0.04772363 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.041389145 = queryNorm
                0.12611452 = fieldWeight in 1522, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1522)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Abstract
    Paper presented at the 30th Annual Conference of the National Federation of Astracting and Information Services, Philadelphia, 28 Feb-2 Mar 88. In recent years, the amount and the variety of available machine-readable data, new technologies have been introduced, such as high density storage devices, and fancy graphic displays useful for information transformation and access. New approaches have also been considered for processing the stored data based on the construction of knowledge bases representing the contents and structure of the information, and the use of expert system techniques to control the user-system interactions. Provides a brief evaluation of the new information processing technologies, and of the software methods proposed for information manipulation.
    Type
    a
  3. Prasher, R.G.: Evaluation of indexing system (1989) 0.00
    0.0012159493 = product of:
      0.0024318986 = sum of:
        0.0024318986 = product of:
          0.004863797 = sum of:
            0.004863797 = weight(_text_:a in 4998) [ClassicSimilarity], result of:
              0.004863797 = score(doc=4998,freq=2.0), product of:
                0.04772363 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.041389145 = queryNorm
                0.10191591 = fieldWeight in 4998, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0625 = fieldNorm(doc=4998)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Type
    a
  4. Jochum, F.; Weissmann, V.: Struktur und Elemente des Information Retrieval Experiments (1985) 0.00
    0.0012159493 = product of:
      0.0024318986 = sum of:
        0.0024318986 = product of:
          0.004863797 = sum of:
            0.004863797 = weight(_text_:a in 114) [ClassicSimilarity], result of:
              0.004863797 = score(doc=114,freq=2.0), product of:
                0.04772363 = queryWeight, product of:
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.041389145 = queryNorm
                0.10191591 = fieldWeight in 114, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  1.153047 = idf(docFreq=37942, maxDocs=44218)
                  0.0625 = fieldNorm(doc=114)
          0.5 = coord(1/2)
      0.5 = coord(1/2)
    
    Type
    a