Search (40 results, page 1 of 2)

0.08390742 = product of:
  0.18879169 = sum of:
    0.018934188 = weight(_text_:of in 5072) [ClassicSimilarity], result of:
      0.018934188 = score(doc=5072,freq=10.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.3090647 = fieldWeight in 5072, product of:
          3.1622777 = tf(freq=10.0), with freq of:
            10.0 = termFreq=10.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0625 = fieldNorm(doc=5072)
    0.03270373 = weight(_text_:systems in 5072) [ClassicSimilarity], result of:
      0.03270373 = score(doc=5072,freq=2.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.2716328 = fieldWeight in 5072, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.0625 = fieldNorm(doc=5072)
    0.054498006 = weight(_text_:software in 5072) [ClassicSimilarity], result of:
      0.054498006 = score(doc=5072,freq=2.0), product of:
        0.15541996 = queryWeight, product of:
          3.9671519 = idf(docFreq=2274, maxDocs=44218)
          0.03917671 = queryNorm
        0.35064998 = fieldWeight in 5072, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.9671519 = idf(docFreq=2274, maxDocs=44218)
          0.0625 = fieldNorm(doc=5072)
    0.082655765 = product of:
      0.16531153 = sum of:
        0.16531153 = weight(_text_:packages in 5072) [ClassicSimilarity], result of:
          0.16531153 = score(doc=5072,freq=2.0), product of:
            0.2706874 = queryWeight, product of:
              6.9093957 = idf(docFreq=119, maxDocs=44218)
              0.03917671 = queryNorm
            0.6107101 = fieldWeight in 5072, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              6.9093957 = idf(docFreq=119, maxDocs=44218)
              0.0625 = fieldNorm(doc=5072)
      0.5 = coord(1/2)
  0.44444445 = coord(4/9)

Abstract

Comments on the relative rarity of research articles on theoretical aspects of subject indexing in computerised retrieval systems and the predominance of articles on software packages and hardware. Concludes that controlled indexing still has a future but points to major differences from the past

Source

Computers in libraries international 91. Proceedings of the 5th Annual Conference on Computers in Libraries, London, February 1991

0.041063324 = product of:
  0.092392474 = sum of:
    0.041947264 = weight(_text_:applications in 2337) [ClassicSimilarity], result of:
      0.041947264 = score(doc=2337,freq=2.0), product of:
        0.17247584 = queryWeight, product of:
          4.4025097 = idf(docFreq=1471, maxDocs=44218)
          0.03917671 = queryNorm
        0.2432066 = fieldWeight in 2337, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          4.4025097 = idf(docFreq=1471, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2337)
    0.016735615 = weight(_text_:of in 2337) [ClassicSimilarity], result of:
      0.016735615 = score(doc=2337,freq=20.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.27317715 = fieldWeight in 2337, product of:
          4.472136 = tf(freq=20.0), with freq of:
            20.0 = termFreq=20.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2337)
    0.020439833 = weight(_text_:systems in 2337) [ClassicSimilarity], result of:
      0.020439833 = score(doc=2337,freq=2.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.1697705 = fieldWeight in 2337, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2337)
    0.013269759 = product of:
      0.026539518 = sum of:
        0.026539518 = weight(_text_:22 in 2337) [ClassicSimilarity], result of:
          0.026539518 = score(doc=2337,freq=2.0), product of:
            0.13719016 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03917671 = queryNorm
            0.19345059 = fieldWeight in 2337, 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=2337)
      0.5 = coord(1/2)
  0.44444445 = coord(4/9)

Abstract

Despite early claims to the contemporary, thesauri continue to find use as access tools for information in the full-text environment. Their mode of use is changing, but this change actually represents an expansion rather than a contrdiction of their utility. Thesauri and similar vocabulary tools can complement full-text access by aiding users in focusing their searches, by supplementing the linguistic analysis of the text search engine, and even by serving as one of the tools used by the linguistic engine for its analysis. While human indexing contunues to be used for many databases, the trend is to increase the use of machine aids for this purpose. All machine-aided indexing (MAI) systems rely on thesauri as the basis for term selection. In the 21st century, the balance of effort between human and machine will change at both input and output, but thesauri will continue to play an important role for the foreseeable future

Date

22. 9.1997 19:16:05

Imprint

Urbana-Champaign, IL : Illinois University at Urbana-Champaign, Graduate School of Library and Information Science

Source

Visualizing subject access for 21st century information resources: Papers presented at the 1997 Clinic on Library Applications of Data Processing, 2-4 Mar 1997, Graduate School of Library and Information Science, University of Illinois at Urbana-Champaign. Ed.: P.A. Cochrane et al

0.036406033 = product of:
  0.10921809 = sum of:
    0.014666359 = weight(_text_:of in 1545) [ClassicSimilarity], result of:
      0.014666359 = score(doc=1545,freq=24.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.23940048 = fieldWeight in 1545, product of:
          4.8989797 = tf(freq=24.0), with freq of:
            24.0 = termFreq=24.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03125 = fieldNorm(doc=1545)
    0.04005373 = weight(_text_:systems in 1545) [ClassicSimilarity], result of:
      0.04005373 = score(doc=1545,freq=12.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.33268085 = fieldWeight in 1545, product of:
          3.4641016 = tf(freq=12.0), with freq of:
            12.0 = termFreq=12.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03125 = fieldNorm(doc=1545)
    0.054498006 = weight(_text_:software in 1545) [ClassicSimilarity], result of:
      0.054498006 = score(doc=1545,freq=8.0), product of:
        0.15541996 = queryWeight, product of:
          3.9671519 = idf(docFreq=2274, maxDocs=44218)
          0.03917671 = queryNorm
        0.35064998 = fieldWeight in 1545, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          3.9671519 = idf(docFreq=2274, maxDocs=44218)
          0.03125 = fieldNorm(doc=1545)
  0.33333334 = coord(3/9)

Abstract

Information or Document Retrieval is the subject of this book. It is not an introductory book, although it is self-contained in the sense that it is not necessary to have a background in the theory or practice of Information Retrieval in order to understand its arguments. The book presents, as clearly as possible, one particular perspective on Information Retrieval, and attempts to say that certain aspects of the theory or practice of the management of documents are more important than others. The majority of Information Retrieval research has been aimed at the more experimentally tractable small-scale systems, and although much of that work has added greatly to our understanding of Information Retrieval it is becoming increasingly apparent that retrieval systems with large data bases of documents are a fundamentally different genre of systems than small-scale systems. If this is so, which is the thesis of this book, then we must now study large information retrieval systems with the same rigor and intensity that we once studied small-scale systems. Hegel observed that the quantitative growth of any system caused qualitative changes to take place in its structure and processes.

Classification

ST 271 Informatik / Monographien / Software und -entwicklung / Datenbanken, Datenbanksysteme, Data base management, Informationssysteme / Einzelne Datenbanksprachen und Datenbanksysteme
ST 270 Informatik / Monographien / Software und -entwicklung / Datenbanken, Datenbanksysteme, Data base management, Informationssysteme

RVK

ST 271 Informatik / Monographien / Software und -entwicklung / Datenbanken, Datenbanksysteme, Data base management, Informationssysteme / Einzelne Datenbanksprachen und Datenbanksysteme
ST 270 Informatik / Monographien / Software und -entwicklung / Datenbanken, Datenbanksysteme, Data base management, Informationssysteme

0.012286034 = product of:
  0.055287153 = sum of:
    0.014818345 = weight(_text_:of in 5608) [ClassicSimilarity], result of:
      0.014818345 = score(doc=5608,freq=8.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.24188137 = fieldWeight in 5608, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0546875 = fieldNorm(doc=5608)
    0.04046881 = weight(_text_:systems in 5608) [ClassicSimilarity], result of:
      0.04046881 = score(doc=5608,freq=4.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.33612844 = fieldWeight in 5608, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.0546875 = fieldNorm(doc=5608)
  0.22222222 = coord(2/9)

Abstract

Discusses the problems in establishing commonly accepted principles for subject retrieval between different bibliographic systems. The Working Group on Principles Underlying Subject Heading Languages was established to devise general principles for any subject retrieval system and to review existing real systems in the light of such principles and compare them in order to evaluate the extent of their coverage and their application in current practices. Provides a background and history of the Working Group. Discusses the principles underlying subject headings and their purposes and the state of the work and major findings

0.011298507 = product of:
  0.050843284 = sum of:
    0.022227516 = weight(_text_:of in 6941) [ClassicSimilarity], result of:
      0.022227516 = score(doc=6941,freq=18.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.36282203 = fieldWeight in 6941, product of:
          4.2426405 = tf(freq=18.0), with freq of:
            18.0 = termFreq=18.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0546875 = fieldNorm(doc=6941)
    0.028615767 = weight(_text_:systems in 6941) [ClassicSimilarity], result of:
      0.028615767 = score(doc=6941,freq=2.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.23767869 = fieldWeight in 6941, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.0546875 = fieldNorm(doc=6941)
  0.22222222 = coord(2/9)

Abstract

Explores the question of whether academic libraries keep up with the changes in the LCSH system. Analysis of the handling of 15 subject headings in 50 academic library catalogues available via the Internet found that libraries are not consistently maintaining subject authority control, or making syndetic references and scope notes in their catalogues. Discusses the results from the perspective of the libraries' performance, performance on the headings overall, performance on references, performance on the type of change made to the headings,a nd performance within 3 widely used onlien catalogue systems (DRA, INNOPAC and NOTIS). Discusses the implications of the findings in relationship to expressions of dissatisfaction with the effectiveness of subject cataloguing expressed by discussion groups on the Internet

0.010530886 = product of:
  0.047388986 = sum of:
    0.012701439 = weight(_text_:of in 2215) [ClassicSimilarity], result of:
      0.012701439 = score(doc=2215,freq=8.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.20732689 = fieldWeight in 2215, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.046875 = fieldNorm(doc=2215)
    0.034687545 = weight(_text_:systems in 2215) [ClassicSimilarity], result of:
      0.034687545 = score(doc=2215,freq=4.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.28811008 = fieldWeight in 2215, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.046875 = fieldNorm(doc=2215)
  0.22222222 = coord(2/9)

Content

Enthält u.a. die Beiträge: CHAN, L.M.: Functions of a subject authority file; ROOD, J.: Practical considerations in dealing with LCSH-mr; GARRISON, W.A.: Practical considerations in using the machine-readable LCSH; BISHOFF, L.: Public access to to the Library of Congress Subject Headings online; MANDEL, C.A.: Multiple vocabularies in subject authority control

Footnote

Rez. in: Canadian library journal 49(1992) S.166 (P. Nicholls): "Basically a collection of the proceedings of a program given at the ALA's 1987 annual conference, the original impetus for the session was to familarize bibliographic utilities, library systems staff, and integrated library system vendors with the recently-released machine-readable LCSH-mr so that they could "integrate this new tool into online bibliographic systems to provide the cataloging, thesaurus maintenance, file maintenance, and retrieval functions associated with subject authority work." These papers were writeen in 1986 and are all about LCSH on magnetic tape. Gads!

0.010530886 = product of:
  0.047388986 = sum of:
    0.012701439 = weight(_text_:of in 5698) [ClassicSimilarity], result of:
      0.012701439 = score(doc=5698,freq=8.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.20732689 = fieldWeight in 5698, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.046875 = fieldNorm(doc=5698)
    0.034687545 = weight(_text_:systems in 5698) [ClassicSimilarity], result of:
      0.034687545 = score(doc=5698,freq=4.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.28811008 = fieldWeight in 5698, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.046875 = fieldNorm(doc=5698)
  0.22222222 = coord(2/9)

Abstract

Describes the shortcomings of search engines for the WWW comparing their current capabilities to those of the first generation CD-ROM products. Some allow phrase searching and most are improving their Boolean searching. Few allow truncation, wild cards or nested logic. They are stateless, losing previous search criteria. Unlike the indexing and classification systems for today's CD-ROMs, those for Web pages are random, unstructured and of variable quality. Considers that at best Web search engines can only offer free text searching. Discusses whether automatic data classification systems such as Infoseek Ultra can overcome the haphazard nature of the Web with neural network technology, and whether Boolean search techniques may be redundant when replaced by technology such as the Euroferret search engine. However, artificial intelligence is rarely successful on huge, varied databases. Relevance ranking and automatic query expansion still use the same simple inverted indexes. Most Web search engines do nothing more than word counting. Further complications arise with foreign languages

0.009684435 = product of:
  0.04357996 = sum of:
    0.019052157 = weight(_text_:of in 3351) [ClassicSimilarity], result of:
      0.019052157 = score(doc=3351,freq=18.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.3109903 = fieldWeight in 3351, product of:
          4.2426405 = tf(freq=18.0), with freq of:
            18.0 = termFreq=18.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.046875 = fieldNorm(doc=3351)
    0.0245278 = weight(_text_:systems in 3351) [ClassicSimilarity], result of:
      0.0245278 = score(doc=3351,freq=2.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.2037246 = fieldWeight in 3351, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.046875 = fieldNorm(doc=3351)
  0.22222222 = coord(2/9)

Abstract

Investigates the extent to which title keywords convey subject content and compares the relative effectiveness of searching title keywords using 2 search strategies to examine whether adjacency operators in title keyword searches are effective in improving recall and precision of online searching. Title keywords from a random sample of titles in the field of economics were searched on FirstSearch, using the WorldCat database, which is equivalent in coverage to the OCLC OLUC, with and without adjacency of the keywords specified. The LCSH of the items retrieved were compared with the sample title subject headings to determine the degree of match or relevance and the values for precision and recall were calculated. Results indicated that, when keywords were discipline specific, adjacency operators improved precision with little degradation of recall. Systems that allow positional operators or rank output by proximity of terms may increase search success

0.009149191 = product of:
  0.041171357 = sum of:
    0.008467626 = weight(_text_:of in 1633) [ClassicSimilarity], result of:
      0.008467626 = score(doc=1633,freq=2.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.13821793 = fieldWeight in 1633, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0625 = fieldNorm(doc=1633)
    0.03270373 = weight(_text_:systems in 1633) [ClassicSimilarity], result of:
      0.03270373 = score(doc=1633,freq=2.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.2716328 = fieldWeight in 1633, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.0625 = fieldNorm(doc=1633)
  0.22222222 = coord(2/9)

Source

Subject indexing: principles and practices in the 90's. Proceedings of the IFLA Satellite Meeting Held in Lisbon, Portugal, 17-18 August 1993, and sponsored by the IFLA Section on Classification and Indexing and the Instituto da Biblioteca Nacional e do Livro, Lisbon, Portugal. Ed.: R.P. Holley et al

0.008273165 = product of:
  0.03722924 = sum of:
    0.012701439 = weight(_text_:of in 386) [ClassicSimilarity], result of:
      0.012701439 = score(doc=386,freq=8.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.20732689 = fieldWeight in 386, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.046875 = fieldNorm(doc=386)
    0.0245278 = weight(_text_:systems in 386) [ClassicSimilarity], result of:
      0.0245278 = score(doc=386,freq=2.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.2037246 = fieldWeight in 386, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.046875 = fieldNorm(doc=386)
  0.22222222 = coord(2/9)

Abstract

Using subject headings for Online Retrieval is an indispensable tool for online system desingners who are developing new systems or refining exicting ones. The book describes subject analysis and subject searching in online catalogs, including the limitations of retrieval, and demonstrates how such limitations can be overcome through system design and programming. The book describes the Library of Congress Subject headings system and system characteristics, shows how information is stored in machine readable files, and offers examples of and recommendations for successful methods. Tables are included to support these recommendations, and diagrams, graphs, and bar charts are used to provide results of data analyses.

0.007977327 = product of:
  0.035897974 = sum of:
    0.014666359 = weight(_text_:of in 3734) [ClassicSimilarity], result of:
      0.014666359 = score(doc=3734,freq=6.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.23940048 = fieldWeight in 3734, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0625 = fieldNorm(doc=3734)
    0.021231614 = product of:
      0.042463228 = sum of:
        0.042463228 = weight(_text_:22 in 3734) [ClassicSimilarity], result of:
          0.042463228 = score(doc=3734,freq=2.0), product of:
            0.13719016 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03917671 = queryNorm
            0.30952093 = fieldWeight in 3734, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0625 = fieldNorm(doc=3734)
      0.5 = coord(1/2)
  0.22222222 = coord(2/9)

Abstract

Most indexed databases now include their thesauri and/or coding in their bibliographic files, searchable at the databases' online connect rates. Assesses the searchability of these on the different hosts. Thesauri and classifications are also available as diskette or CD-ROM products. Describes a number of these, highlighting the diskette thesaurus from IFI/Plenum Data for its flexible databases, the CLAIMS Uniterm and Comprehensive indexes to US chemical patents

Source

Searcher. 3(1995) no.8, S.18-22

0.00742293 = product of:
  0.033403184 = sum of:
    0.012963352 = weight(_text_:of in 2918) [ClassicSimilarity], result of:
      0.012963352 = score(doc=2918,freq=12.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.21160212 = fieldWeight in 2918, product of:
          3.4641016 = tf(freq=12.0), with freq of:
            12.0 = termFreq=12.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2918)
    0.020439833 = weight(_text_:systems in 2918) [ClassicSimilarity], result of:
      0.020439833 = score(doc=2918,freq=2.0), product of:
        0.12039685 = queryWeight, product of:
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.03917671 = queryNorm
        0.1697705 = fieldWeight in 2918, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          3.0731742 = idf(docFreq=5561, maxDocs=44218)
          0.0390625 = fieldNorm(doc=2918)
  0.22222222 = coord(2/9)

Abstract

Reports an algorithmic approach to the automatic generation of thesauri for electronic community systems. The techniques used included terms filtering, automatic indexing, and cluster analysis. The testbed for the research was the Worm Community System, which contains a comprehensive library of specialized community data and literature, currently in use by molecular biologists who study the nematode worm. The resulting worm thesaurus included 2709 researchers' names, 798 gene names, 20 experimental methods, and 4302 subject descriptors. On average, each term had about 90 weighted neighbouring terms indicating relevant concepts. The thesaurus was developed as an online search aide. Tests the worm thesaurus in an experiment with 6 worm researchers of varying degrees of expertise and background. The experiment showed that the thesaurus was an excellent 'memory jogging' device and that it supported learning and serendipitous browsing. Despite some occurrences of obvious noise, the system was useful in suggesting relevant concepts for the researchers' queries and it helped improve concept recall. With a simple browsing interface, an automatic thesaurus can become a useful tool for online search and can assist researchers in exploring and traversing a dynamic and complex electronic community system

Source

Journal of the American Society for Information Science. 46(1995) no.3, S.175-193

0.0074213347 = product of:
  0.033396006 = sum of:
    0.014818345 = weight(_text_:of in 7238) [ClassicSimilarity], result of:
      0.014818345 = score(doc=7238,freq=8.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.24188137 = fieldWeight in 7238, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0546875 = fieldNorm(doc=7238)
    0.018577661 = product of:
      0.037155323 = sum of:
        0.037155323 = weight(_text_:22 in 7238) [ClassicSimilarity], result of:
          0.037155323 = score(doc=7238,freq=2.0), product of:
            0.13719016 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.03917671 = queryNorm
            0.2708308 = fieldWeight in 7238, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.0546875 = fieldNorm(doc=7238)
      0.5 = coord(1/2)
  0.22222222 = coord(2/9)

Abstract

Subject access in library OPACs might be improved for some users by taking advantage of all of the hierarchical relationships which are indicated on existing LCSH entries. Recommends that cross references pointing to broader terms be displayed, in addition to those for narrower and related terms to which users have traditionally benn directed. Traces the old practice back to Charles Cutter, reports on deliberations of the ALCTS Subject Analysis Committee nearly 120 years later. Discusses practical concerns related to implementing the change, including the accuracy of hierarchical relationships in the LCSH system and possible techniques for using the MARC format to generate the cross references

Date

22. 4.1997 20:43:23

0.0027329149 = product of:
  0.024596233 = sum of:
    0.024596233 = weight(_text_:of in 2322) [ClassicSimilarity], result of:
      0.024596233 = score(doc=2322,freq=30.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.4014868 = fieldWeight in 2322, product of:
          5.477226 = tf(freq=30.0), with freq of:
            30.0 = termFreq=30.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.046875 = fieldNorm(doc=2322)
  0.11111111 = coord(1/9)

Abstract

The introduction of computerized post-coordination has solved many of the problems of pre-coordinated subject access. However, the adoption of computerized post-coordination results in the loss of some pre-coordination benefits. Specifically, the effect of hiding terms within the context of others is lost in post-coodination which give lead status to every document term. This results in spurious matches of terms out of context. Library patrons and Internet searchers are increasingly dissatisfied with subject access performance, in part because of unmanageably large retrieval sets. The need to enhance precision and limit the size of retrieval sets motivates this work which proposes partial coordination, an approach which incorporates the advantages of computer search with the ability of pre-coordination to limit spurious partial matches and thereby enhance precision

Source

Journal of the American Society for Information Science. 49(1998) no.14, S.1254-1269

0.002730383 = product of:
  0.024573447 = sum of:
    0.024573447 = weight(_text_:of in 515) [ClassicSimilarity], result of:
      0.024573447 = score(doc=515,freq=22.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.40111488 = fieldWeight in 515, product of:
          4.690416 = tf(freq=22.0), with freq of:
            22.0 = termFreq=22.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0546875 = fieldNorm(doc=515)
  0.11111111 = coord(1/9)

Abstract

Libraries using the LCSH can increase the effectiveness of their subject access. This can be accomplished through one of four methods for applying an increased number of headings: the addition of subject headings in situations where none have been supplied by LC; the use of pattern secondary headings; the use of major + minor techniques; and the use of minor + major techniques. Each of these methods will provide additional subject access to supplement that produced by the Library of Congress

0.0026033178 = product of:
  0.023429861 = sum of:
    0.023429861 = weight(_text_:of in 2775) [ClassicSimilarity], result of:
      0.023429861 = score(doc=2775,freq=20.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.38244802 = fieldWeight in 2775, product of:
          4.472136 = tf(freq=20.0), with freq of:
            20.0 = termFreq=20.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0546875 = fieldNorm(doc=2775)
  0.11111111 = coord(1/9)

Abstract

Browse searching of online catalogs and electronic indexes is a popular means of retrieving information, but some subject heading lists are so extensive that browsing them can be difficult and time-consuming. This resaerch tested one way of presenting a browse interface to reduce the amount of scanning of subject headings required. It found that a hierarchical presentation of headings reduced the amount of scanning required by more than 50% without any reduction in the effectiveness of the search. Better browsable displays of this sort can improve the efficiency of searching but appear not to alter effectivenenss

0.002544205 = product of:
  0.022897845 = sum of:
    0.022897845 = weight(_text_:of in 2230) [ClassicSimilarity], result of:
      0.022897845 = score(doc=2230,freq=26.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.37376386 = fieldWeight in 2230, product of:
          5.0990195 = tf(freq=26.0), with freq of:
            26.0 = termFreq=26.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.046875 = fieldNorm(doc=2230)
  0.11111111 = coord(1/9)

Abstract

Experimental evidence suggests that enhancing the subject content of OPAC records can improve retrieval performance. This is based on the use of natural language index terms derived from the table of contents and back-of-the-book index of documents. The research reported here investigates the alternative approach of translating these natural language terms into controlled vocabulary. Subject queries were collected by interview at the catalogue, and indexing of the queries demonstrated the impressive ability of PRECIS, and to a lesser extent LCSH, to represent users' information needs. DDC performed poorly in this respect. The assumption was made that an index language adequately specific to represent users' queries should be adequate to represent document contents. Searches were carried out on three test databases, and both natural language and PRECIS enhancement of MARC records increased the number of relevant documents found, with PRECIS showing the better performance. However, with weak stemming the advantage of PRECIS was lost. Consideration must also be given to the potential advantages of controlled vocabulary, over and above basic retrieval performance measures

Source

Journal of documentation. 48(1992) no.3, S.291-309

0.0024443932 = product of:
  0.021999538 = sum of:
    0.021999538 = weight(_text_:of in 154) [ClassicSimilarity], result of:
      0.021999538 = score(doc=154,freq=6.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.3591007 = fieldWeight in 154, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.09375 = fieldNorm(doc=154)
  0.11111111 = coord(1/9)

Source

Journal of the American Society for information Science. 41(1990) no.8, S.547-559

0.0023284785 = product of:
  0.020956306 = sum of:
    0.020956306 = weight(_text_:of in 1284) [ClassicSimilarity], result of:
      0.020956306 = score(doc=1284,freq=4.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.34207192 = fieldWeight in 1284, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.109375 = fieldNorm(doc=1284)
  0.11111111 = coord(1/9)

Source

Encyclopedia of library and information science. Vol.50, [=Suppl.13]

0.002304596 = product of:
  0.020741362 = sum of:
    0.020741362 = weight(_text_:of in 2642) [ClassicSimilarity], result of:
      0.020741362 = score(doc=2642,freq=12.0), product of:
        0.061262865 = queryWeight, product of:
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.03917671 = queryNorm
        0.33856338 = fieldWeight in 2642, product of:
          3.4641016 = tf(freq=12.0), with freq of:
            12.0 = termFreq=12.0
          1.5637573 = idf(docFreq=25162, maxDocs=44218)
          0.0625 = fieldNorm(doc=2642)
  0.11111111 = coord(1/9)

Abstract

In online retrieval search results do not always match the intent in spite of using correct keywords (descriptors). One of the causes of this problem is found in the hierarchical structures of the thesaurus, which often contains relations between broader and narrower concepts, the opposite of which is not necessarily true. Some examples are described from 2 thesauri, MeSH and JICST. In these cases searchers need to make an effort to increase precision