Search (2 results, page 1 of 1)

0.008955287 = product of:
  0.035821147 = sum of:
    0.035821147 = product of:
      0.071642295 = sum of:
        0.071642295 = weight(_text_:access in 2259) [ClassicSimilarity], result of:
          0.071642295 = score(doc=2259,freq=6.0), product of:
            0.15778996 = queryWeight, product of:
              3.389428 = idf(docFreq=4053, maxDocs=44218)
              0.046553567 = queryNorm
            0.45403582 = fieldWeight in 2259, product of:
              2.4494898 = tf(freq=6.0), with freq of:
                6.0 = termFreq=6.0
              3.389428 = idf(docFreq=4053, maxDocs=44218)
              0.0546875 = fieldNorm(doc=2259)
      0.5 = coord(1/2)
  0.25 = coord(1/4)

Abstract

51 subject searches were performed in an online catalog containing about 4,5 million records. Their success was judges in terms of lists of items, known to be relevant to the various topics, compiled by subject specialists (faculty members or authors of articles in specialized encyclopedias). Many of the items known to be relevant were not retrieved, even in very broad searches that sometimes retrieved several hundred records, and very little could be done to make them retrievable within the constraints of present cataloging practice. Librarians should recognize that library catalogs, as now implemented, offer only the most primitive of subject access and should seek to develop different types of subject access tools. - Vgl auch Letter (B.H. Weinberg) in: LTRS 36(1992) S.123-124.

0.008863435 = product of:
  0.03545374 = sum of:
    0.03545374 = product of:
      0.07090748 = sum of:
        0.07090748 = weight(_text_:access in 1788) [ClassicSimilarity], result of:
          0.07090748 = score(doc=1788,freq=8.0), product of:
            0.15778996 = queryWeight, product of:
              3.389428 = idf(docFreq=4053, maxDocs=44218)
              0.046553567 = queryNorm
            0.4493789 = fieldWeight in 1788, product of:
              2.828427 = tf(freq=8.0), with freq of:
                8.0 = termFreq=8.0
              3.389428 = idf(docFreq=4053, maxDocs=44218)
              0.046875 = fieldNorm(doc=1788)
      0.5 = coord(1/2)
  0.25 = coord(1/4)

Abstract

Reports results of an analysis of 205 randomly selected records from the OCLC OLUC, to test the assumption that online catalogues have greatly improved subject searching capabilities, over card catalogues, by making other fields in the records searchable as subject access points (SAPs). Results showed considerable overlap (duplication) among the SAPs provided by the title, subject heading and classification number fields. On average, little more than 4 unique, unduplicated access points were found per record. Where title and classification number fields do add some access points not provided by subject headings, the increase is less than many librarians might be expected. Suggests that OPACs might outperform catalogues more in precision than in recall by allowing greater discrimination in searching; terms from different fields may be combined; titles offer greater specifity; searches can be limited by date, language or other criteria