Search (265 results, page 14 of 14)

0.008918746 = product of:
  0.017837493 = sum of:
    0.017837493 = product of:
      0.035674985 = sum of:
        0.035674985 = weight(_text_:x in 2606) [ClassicSimilarity], result of:
          0.035674985 = score(doc=2606,freq=2.0), product of:
            0.19116588 = queryWeight, product of:
              4.2226825 = idf(docFreq=1761, maxDocs=44218)
              0.045271195 = queryNorm
            0.18661796 = fieldWeight in 2606, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              4.2226825 = idf(docFreq=1761, maxDocs=44218)
              0.03125 = fieldNorm(doc=2606)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Abstract

The first edition of this work, published in 1974, was designed for librarians. It contained an alphabetical listing of subject headings in six widely used sourdes: LCSH, Sears List, Readers' Guide to Periodical Literature, New York Times Index, PAIS, and Business Periodical Index. It was a useful and popular tool, but the rapid growth of information has resulted in new access tools, both print and online, and new subject headings. The second edition of Cross-reference index reflects this expansion. The editors have added headings from the Thesaurus of ERIC Descriptors, the Thesaurus of of Psychological Index Terms, and the Subject Guide to IAC Databases to provide broader coverage of current affairs, social science, amd business. They have also redesigned the format to encourage use by the public as well as by professionals. The expansion has increased the number of main headings from 1.386 to 1.684, and the new format directs users up to 50 comparable or related terms rather than three. This creates easy access to 42.000 search terms. Cross-reference index is in two parts: an alphabetical index and a main entry section. Users consult the alphabetical section first. This refers them to one or more main-entry headings, which are in alphabetical order and numbered to correspond to the index. Under each main entry the related subject headings are arranged alphabetically in a chart format with eight columns, one for each source. An X in a colums shows that the particular source uses a given term. These charts are easy to use and make indexing quirks readily apparent. Under the entry Blood, for example, one can see that LC uses Blood-vessels, while Readers' Guide, Sears, and Psychinfo use Blood vessels. Under Broadcasting, Readers' Guide uses Television broadcasting--News, LC and IAC use Television broadcasting of news, while PAIS uses Television--news. Using this book will cut down on the frustration that often accompanies research. The diversity of the sources included will also provide several points of view, offerings users new approaches that they might not have considered. Cross-reference Index belongs in all reference collections that own most of the sources indexed.

0.008918746 = product of:
  0.017837493 = sum of:
    0.017837493 = product of:
      0.035674985 = sum of:
        0.035674985 = weight(_text_:x in 3641) [ClassicSimilarity], result of:
          0.035674985 = score(doc=3641,freq=2.0), product of:
            0.19116588 = queryWeight, product of:
              4.2226825 = idf(docFreq=1761, maxDocs=44218)
              0.045271195 = queryNorm
            0.18661796 = fieldWeight in 3641, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              4.2226825 = idf(docFreq=1761, maxDocs=44218)
              0.03125 = fieldNorm(doc=3641)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Abstract

The second Cranfield experiment (Cranfield II) in the mid-1960s challenged assumptions held by librarians for nearly a century, namely, that the objective of providing subject access was to bring together all materials an a given topic and that the achieving of this objective required vocabulary control in the form of an index language. The results of Cranfield II were replicated by other retrieval experiments quick to follow its lead and increasing support was given to the opinion that natural language information systems could perform at least as effectively, and certainly more economically, than those employing index languages. When the results of empirical research dramatically counter conventional wisdom, an obvious course is to question the validity of the research and, in the case of retrieval experiments, this eventually happened. Retrieval experiments were criticized for their artificiality, their unrepresentative sampies, and their problematic definitions-particularly the definition of relevance. In the minds of some, at least, the relative merits of natural languages vs. indexing languages continued to be an unresolved issue. As with many eitherlor options, a seemingly safe course to follow is to opt for "both," and indeed there seems to be an increasing amount of counsel advising a combination of natural language and index language search capabilities. One strong voice offering such counsel is that of Robert Fugmann, a chemist by training, a theoretician by predilection, and, currently, a practicing information scientist at Hoechst AG, Frankfurt/Main. This selection from his writings sheds light an the capabilities and limitations of both kinds of indexing. Its special significance lies in the fact that its arguments are based not an empirical but an rational grounds. Fugmann's major argument starts from the observation that in natural language there are essentially two different kinds of concepts: 1) individual concepts, repre sented by names of individual things (e.g., the name of the town Augsburg), and 2) general concepts represented by names of classes of things (e.g., pesticides). Individual concepts can be represented in language simply and succinctly, often by a single string of alphanumeric characters; general concepts, an the other hand, can be expressed in a multiplicity of ways. The word pesticides refers to the concept of pesticides, but also referring to this concept are numerous circumlocutions, such as "Substance X was effective against pests." Because natural language is capable of infinite variety, we cannot predict a priori the manifold ways a general concept, like pesticides, will be represented by any given author. It is this lack of predictability that limits natural language retrieval and causes poor precision and recall. Thus, the essential and defining characteristic of an index language ls that it is a tool for representational predictability.

0.0076670274 = product of:
  0.015334055 = sum of:
    0.015334055 = product of:
      0.03066811 = sum of:
        0.03066811 = weight(_text_:22 in 3113) [ClassicSimilarity], result of:
          0.03066811 = score(doc=3113,freq=2.0), product of:
            0.15853201 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.045271195 = queryNorm
            0.19345059 = fieldWeight in 3113, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0390625 = fieldNorm(doc=3113)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Date

15. 1.2005 14:10:22

0.006133622 = product of:
  0.012267244 = sum of:
    0.012267244 = product of:
      0.024534488 = sum of:
        0.024534488 = weight(_text_:22 in 3624) [ClassicSimilarity], result of:
          0.024534488 = score(doc=3624,freq=2.0), product of:
            0.15853201 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.045271195 = queryNorm
            0.15476047 = fieldWeight in 3624, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03125 = fieldNorm(doc=3624)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Footnote

Original in: Pettee, J.: The history and theory of the alphabetical subject approach to books. New York: Wilson 1946. S.22-25.

0.005366919 = product of:
  0.010733838 = sum of:
    0.010733838 = product of:
      0.021467676 = sum of:
        0.021467676 = weight(_text_:22 in 3644) [ClassicSimilarity], result of:
          0.021467676 = score(doc=3644,freq=2.0), product of:
            0.15853201 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.045271195 = queryNorm
            0.1354154 = fieldWeight in 3644, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.02734375 = fieldNorm(doc=3644)
      0.5 = coord(1/2)
  0.5 = coord(1/2)

Footnote

Original in: Information retrieval today: papers presented at an Institute conducted by the Library School and the Center for Continuation Study, University of Minnesota, Sept. 19-22, 1962. Ed. by Wesley Simonton. Minneapolis, Minn.: The Center, 1963. S.21-36.