Search (23 results, page 1 of 2)

0.004738532 = product of:
  0.02843119 = sum of:
    0.02843119 = weight(_text_:und in 2327) [ClassicSimilarity], result of:
      0.02843119 = score(doc=2327,freq=2.0), product of:
        0.09675359 = queryWeight, product of:
          2.216367 = idf(docFreq=13101, maxDocs=44218)
          0.043654136 = queryNorm
        0.29385152 = fieldWeight in 2327, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          2.216367 = idf(docFreq=13101, maxDocs=44218)
          0.09375 = fieldNorm(doc=2327)
  0.16666667 = coord(1/6)

Source

Pragmatische Aspekte beim Entwurf und Betrieb von Informationssystemen: Proc. des 1. Int. Symposiums für Informationswissenschaft, Universität Konstanz, 17.-19.10.1990. Hrsg.: J. Herget u. R. Kuhlen

0.0030914443 = product of:
  0.018548666 = sum of:
    0.018548666 = weight(_text_:in in 1938) [ClassicSimilarity], result of:
      0.018548666 = score(doc=1938,freq=6.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.3123684 = fieldWeight in 1938, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.09375 = fieldNorm(doc=1938)
  0.16666667 = coord(1/6)

Footnote

Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.323-328.

0.0026606917 = product of:
  0.01596415 = sum of:
    0.01596415 = weight(_text_:in in 7410) [ClassicSimilarity], result of:
      0.01596415 = score(doc=7410,freq=10.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.26884392 = fieldWeight in 7410, product of:
          3.1622777 = tf(freq=10.0), with freq of:
            10.0 = termFreq=10.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.0625 = fieldNorm(doc=7410)
  0.16666667 = coord(1/6)

Abstract

Contribution to an issue devoted to the 6th Annual International Conference of the Special Interest Group on Information Retrieval of the Association for Computing Machinery (USA) held at the National Library of Medicine, Bethesda, Maryland, from 6-8 June 83. The following papers were presented in session 12 which was a panel on key issues in information retrieval: SALTON, G.: Research problems in automatic information retrieval; RIJSBERGEN, C.J. van: Information retrieval: new directions, old solutions; MARON, M.E.: Open problems in information retrieval

0.0025241538 = product of:
  0.015144923 = sum of:
    0.015144923 = weight(_text_:in in 77) [ClassicSimilarity], result of:
      0.015144923 = score(doc=77,freq=4.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.25504774 = fieldWeight in 77, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.09375 = fieldNorm(doc=77)
  0.16666667 = coord(1/6)

Footnote

Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.60-84.

0.0023797948 = product of:
  0.014278769 = sum of:
    0.014278769 = weight(_text_:in in 3910) [ClassicSimilarity], result of:
      0.014278769 = score(doc=3910,freq=2.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.24046129 = fieldWeight in 3910, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.125 = fieldNorm(doc=3910)
  0.16666667 = coord(1/6)

0.0023797948 = product of:
  0.014278769 = sum of:
    0.014278769 = weight(_text_:in in 5445) [ClassicSimilarity], result of:
      0.014278769 = score(doc=5445,freq=2.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.24046129 = fieldWeight in 5445, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.125 = fieldNorm(doc=5445)
  0.16666667 = coord(1/6)

0.0023797948 = product of:
  0.014278769 = sum of:
    0.014278769 = weight(_text_:in in 5476) [ClassicSimilarity], result of:
      0.014278769 = score(doc=5476,freq=2.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.24046129 = fieldWeight in 5476, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.125 = fieldNorm(doc=5476)
  0.16666667 = coord(1/6)

0.0023797948 = product of:
  0.014278769 = sum of:
    0.014278769 = weight(_text_:in in 5484) [ClassicSimilarity], result of:
      0.014278769 = score(doc=5484,freq=2.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.24046129 = fieldWeight in 5484, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.125 = fieldNorm(doc=5484)
  0.16666667 = coord(1/6)

0.0021034614 = product of:
  0.012620768 = sum of:
    0.012620768 = weight(_text_:in in 1934) [ClassicSimilarity], result of:
      0.012620768 = score(doc=1934,freq=4.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.21253976 = fieldWeight in 1934, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.078125 = fieldNorm(doc=1934)
  0.16666667 = coord(1/6)

Footnote

Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.273-280.

0.0021034614 = product of:
  0.012620768 = sum of:
    0.012620768 = weight(_text_:in in 1949) [ClassicSimilarity], result of:
      0.012620768 = score(doc=1949,freq=4.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.21253976 = fieldWeight in 1949, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.078125 = fieldNorm(doc=1949)
  0.16666667 = coord(1/6)

Footnote

Wiederabgedruckt in: Readings in information retrieval. Ed.: K. Sparck Jones u. P. Willett. San Francisco: Morgan Kaufmann 1997. S.478-483.

0.0020823204 = product of:
  0.012493922 = sum of:
    0.012493922 = weight(_text_:in in 4901) [ClassicSimilarity], result of:
      0.012493922 = score(doc=4901,freq=8.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.21040362 = fieldWeight in 4901, product of:
          2.828427 = tf(freq=8.0), with freq of:
            8.0 = termFreq=8.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.0546875 = fieldNorm(doc=4901)
  0.16666667 = coord(1/6)

Abstract

Current approaches to the analysis of natural language text are not viable for documents of unrestricted scope. A global text analysis system is proposed designed to identify homogeneous text environments in which the meaning of text words and phrases remains unambiguous, and useful term relationships may be automatically determined. The proposed methods include document clustering methods, as well as comparisons of local document excerpts in specified global contexts, leading to structured text representations in which similar texts, or text excerpts, are appropriately linked

Source

ASIS'90: Information in the year 2000, from research to applications. Proc. of the 53rd Annual Meeting of the American Society for Information Science, Toronto, Canada, 4.-8.11.1990. Ed. by Diana Henderson

0.0020823204 = product of:
  0.012493922 = sum of:
    0.012493922 = weight(_text_:in in 7864) [ClassicSimilarity], result of:
      0.012493922 = score(doc=7864,freq=2.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.21040362 = fieldWeight in 7864, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.109375 = fieldNorm(doc=7864)
  0.16666667 = coord(1/6)

0.0020609628 = product of:
  0.012365777 = sum of:
    0.012365777 = weight(_text_:in in 2331) [ClassicSimilarity], result of:
      0.012365777 = score(doc=2331,freq=6.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.2082456 = fieldWeight in 2331, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.0625 = fieldNorm(doc=2331)
  0.16666667 = coord(1/6)

Abstract

A classified or clustered file is one where related or similar records are grouped into classes or clusters of items in such a way that all itmes within a cluster are jointly retrievable. Clustered files are easily adapted to to broad and narrow search strategies, and simple file updating methods are available. An inexpensive file clustering method applicable to large files is given together with appropriate file search methods

Source

Kooperation in der Klassifikation I. Proc. der Sekt.1-3 der 2. Fachtagung der Gesellschaft für Klassifikation, Frankfurt-Hoechst, 6.-7.4.1978. Bearb.: W. Dahlberg

0.0020609628 = product of:
  0.012365777 = sum of:
    0.012365777 = weight(_text_:in in 6507) [ClassicSimilarity], result of:
      0.012365777 = score(doc=6507,freq=6.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.2082456 = fieldWeight in 6507, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.0625 = fieldNorm(doc=6507)
  0.16666667 = coord(1/6)

Abstract

In many practical information retrieval situations, it is necessary to process heterogeneous text databases that vary greatly in scope and coverage and deal with many different subjects. In such an environment it is important to provide flexible access to individual text pieces and to structure the collection so that related text elements are identified and properly linked. Describes methods for the automatic structuring of heterogeneous text collections and the construction of browsing tools and access procedures that facilitate collection use. Illustrates these emthods with searches using a large automated encyclopedia

0.0018033426 = product of:
  0.010820055 = sum of:
    0.010820055 = weight(_text_:in in 5467) [ClassicSimilarity], result of:
      0.010820055 = score(doc=5467,freq=6.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.1822149 = fieldWeight in 5467, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.0546875 = fieldNorm(doc=5467)
  0.16666667 = coord(1/6)

Abstract

The development of a given discipline in science and technology often depends on the availability of theorie capable of describing the processes which control the field and of modelling the interactions between the processes. The absence of an accepted theory of information retrieval has benn blamed for the relative disorder and the lack of technical advances in the area. The main mathematical approaches to information retrieval are examined in this study, including both algebraic and probabilistic models, and the difficulties which impede the formalization of information retrieval processes are described. A number of developments are covered where new theoretical understandings have directly led to the improvemenet of retrieval techniques and operations

0.0017848461 = product of:
  0.010709076 = sum of:
    0.010709076 = weight(_text_:in in 2409) [ClassicSimilarity], result of:
      0.010709076 = score(doc=2409,freq=2.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.18034597 = fieldWeight in 2409, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.09375 = fieldNorm(doc=2409)
  0.16666667 = coord(1/6)

0.0015457221 = product of:
  0.009274333 = sum of:
    0.009274333 = weight(_text_:in in 5699) [ClassicSimilarity], result of:
      0.009274333 = score(doc=5699,freq=6.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.1561842 = fieldWeight in 5699, product of:
          2.4494898 = tf(freq=6.0), with freq of:
            6.0 = termFreq=6.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.046875 = fieldNorm(doc=5699)
  0.16666667 = coord(1/6)

Abstract

The Smart information retrieval project emphazises completely automatic approaches to the understanding and retrieval of large quantities of text. The work in the TREC-2 environment continues, performing both routing and ad hoc experiments. The ad hoc work extends investigations into combining global similarities, giving an overall indication of how a document matches a query, with local similarities identifying a smaller part of the document that matches the query. The performance of ad hoc runs is good, but it is clear that full advantage of the available local information is not been taken advantage of. The routing experiments use conventional relevance feedback approaches to routing, but with a much greater degree of query expansion than was previously done. The length of a query vector is increased by a factor of 5 to 10 by adding terms found in previously seen relevant documents. This approach improves effectiveness by 30-40% over the original query

Theme

Semantisches Umfeld in Indexierung u. Retrieval

0.0014724231 = product of:
  0.008834538 = sum of:
    0.008834538 = weight(_text_:in in 4151) [ClassicSimilarity], result of:
      0.008834538 = score(doc=4151,freq=4.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.14877784 = fieldWeight in 4151, product of:
          2.0 = tf(freq=4.0), with freq of:
            4.0 = termFreq=4.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.0546875 = fieldNorm(doc=4151)
  0.16666667 = coord(1/6)

Abstract

Two widerly used criteria for evaluating the effectiveness of information retrieval systems are, respectively, the recall and the precision. Since the determiniation of these measures is dependent on a distinction between documents which are relevant to a given query and documents which are not relevant to that query, it has sometimes been claimed that an accurate, generally valid evaluation cannot be based on recall and precision measure. A study was made to determine the effect of variations in relevance assesments do not produce significant variations in average recall and precision. It thus appears that properly computed recall and precision data may represent effectiveness indicators which are gemerally valid for many distinct user classes.

0.0013303459 = product of:
  0.007982075 = sum of:
    0.007982075 = weight(_text_:in in 3650) [ClassicSimilarity], result of:
      0.007982075 = score(doc=3650,freq=10.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.13442196 = fieldWeight in 3650, product of:
          3.1622777 = tf(freq=10.0), with freq of:
            10.0 = termFreq=10.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.03125 = fieldNorm(doc=3650)
  0.16666667 = coord(1/6)

Abstract

The attempt to computerize a process, such as indexing, abstracting, classifying, or retrieving information, begins with an analysis of the process into its intellectual and nonintellectual components. That part of the process which is amenable to computerization is mechanical or algorithmic. What is not is intellectual or creative and requires human intervention. Gerard Salton has been an innovator, experimenter, and promoter in the area of mechanized information systems since the early 1960s. He has been particularly ingenious at analyzing the process of information retrieval into its algorithmic components. He received a doctorate in applied mathematics from Harvard University before moving to the computer science department at Cornell, where he developed a prototype automatic retrieval system called SMART. Working with this system he and his students contributed for over a decade to our theoretical understanding of the retrieval process. On a more practical level, they have contributed design criteria for operating retrieval systems. The following selection presents one of the early descriptions of the SMART system; it is valuable as it shows the direction automatic retrieval methods were to take beyond simple word-matching techniques. These include various word normalization techniques to improve recall, for instance, the separation of words into stems and affixes; the correlation and clustering, using statistical association measures, of related terms; and the identification, using a concept thesaurus, of synonymous, broader, narrower, and sibling terms. They include, as weIl, techniques, both linguistic and statistical, to deal with the thorny problem of how to automatically extract from texts index terms that consist of more than one word. They include weighting techniques and various documentrequest matching algorithms. Significant among the latter are those which produce a retrieval output of citations ranked in relevante order. During the 1970s, Salton and his students went an to further refine these various techniques, particularly the weighting and statistical association measures. Many of their early innovations seem commonplace today. Some of their later techniques are still ahead of their time and await technological developments for implementation. The particular focus of the selection that follows is an the evaluation of a particular component of the SMART system, a multilingual thesaurus. By mapping English language expressions and their German equivalents to a common concept number, the thesaurus permitted the automatic processing of German language documents against English language queries and vice versa. The results of the evaluation, as it turned out, were somewhat inconclusive. However, this SMART experiment suggested in a bold and optimistic way how one might proceed to answer such complex questions as What is meant by retrieval language compatability? How it is to be achieved, and how evaluated?

Footnote

Original in: Journal of the American Society for Information Science 21(1970) no.3, S.187-194.

0.0011898974 = product of:
  0.0071393843 = sum of:
    0.0071393843 = weight(_text_:in in 5250) [ClassicSimilarity], result of:
      0.0071393843 = score(doc=5250,freq=2.0), product of:
        0.059380736 = queryWeight, product of:
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.043654136 = queryNorm
        0.120230645 = fieldWeight in 5250, product of:
          1.4142135 = tf(freq=2.0), with freq of:
            2.0 = termFreq=2.0
          1.3602545 = idf(docFreq=30841, maxDocs=44218)
          0.0625 = fieldNorm(doc=5250)
  0.16666667 = coord(1/6)

Abstract

Substatioal misgivings have been voiced over the years about the methodologies used to evaluate IR procedures and about the credibility of many of the available test results. In this note, an attempt is made to review the state of retrieval evaluation and to separate certain misgivings about the design of retrieval tests from conclusions that can legitimately be drawn from the evaluation results