Search (7 results, page 1 of 1)

Leydesdorff, L.: Similarity measures, author cocitation Analysis, and information theory (2005) 0.01
```
0.012331214 = product of:
  0.03699364 = sum of:
    0.03699364 = product of:
      0.07398728 = sum of:
        0.07398728 = weight(_text_:methodology in 3471) [ClassicSimilarity], result of:
          0.07398728 = score(doc=3471,freq=2.0), product of:
            0.21236731 = queryWeight, product of:
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.047143444 = queryNorm
            0.348393 = fieldWeight in 3471, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.0546875 = fieldNorm(doc=3471)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)
```
Abstract

The use of Pearson's correlation coefficient in Author Cocitation Analysis was compared with Salton's cosine measure in a number of recent contributions. Unlike the Pearson correlation, the cosine is insensitive to the number of zeros. However, one has the option of applying a logarithmic transformation in correlation analysis. Information caiculus is based an both the logarithmic transformation and provides a non-parametric statistics. Using this methodology, one can cluster a document set in a precise way and express the differences in terms of bits of information. The algorithm is explained and used an the data set, which was made the subject of this discussion.
Leydesdorff, L.: ¬A sociological theory of communication : the self-organization of the knowledge-based society (2001) 0.01
```
0.010569612 = product of:
  0.031708833 = sum of:
    0.031708833 = product of:
      0.063417666 = sum of:
        0.063417666 = weight(_text_:methodology in 184) [ClassicSimilarity], result of:
          0.063417666 = score(doc=184,freq=2.0), product of:
            0.21236731 = queryWeight, product of:
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.047143444 = queryNorm
            0.29862255 = fieldWeight in 184, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.046875 = fieldNorm(doc=184)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)
```
Footnote

Rez. in: JASIST 53(2002) no.1, S.61-62 (E.G. Ackermann): "This brief summary cannot do justice to the intellectual depth, philosophical richness of the theoretical models, and their implications presented by Leydesdorff in his book. Next to this, the caveats presented earlier in this review are relatively minor. For all that, this book is not an "easy" read, nor is it for the theoretically or philosophically faint of heart. The content is certainly accessible to those with the interest and the stamina to see it through to the end, and would repay those who reread it with further insight and understanding. This book is recommended especially for the reader who is looking for a well-developed, general sociological theory of communication with a strong philosophical basis upon which to build a postmodern, deconstructionist research methodology"
Bensman, S.J.; Leydesdorff, L.: Definition and identification of journals as bibliographic and subject entities : librarianship versus ISI Journal Citation Reports methods and their effect on citation measures (2009) 0.01
```
0.010569612 = product of:
  0.031708833 = sum of:
    0.031708833 = product of:
      0.063417666 = sum of:
        0.063417666 = weight(_text_:methodology in 2840) [ClassicSimilarity], result of:
          0.063417666 = score(doc=2840,freq=2.0), product of:
            0.21236731 = queryWeight, product of:
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.047143444 = queryNorm
            0.29862255 = fieldWeight in 2840, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.046875 = fieldNorm(doc=2840)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)
```
Abstract

This paper explores the ISI Journal Citation Reports (JCR) bibliographic and subject structures through Library of Congress (LC) and American research libraries cataloging and classification methodology. The 2006 Science Citation Index JCR Behavioral Sciences subject category journals are used as an example. From the library perspective, the main fault of the JCR bibliographic structure is that the JCR mistakenly identifies journal title segments as journal bibliographic entities, seriously affecting journal rankings by total cites and the impact factor. In respect to JCR subject structure, the title segment, which constitutes the JCR bibliographic basis, is posited as the best bibliographic entity for the citation measurement of journal subject relationships. Through factor analysis and other methods, the JCR subject categorization of journals is tested against their LC subject headings and classification. The finding is that JCR and library journal subject analyses corroborate, clarify, and correct each other.
Leydesdorff, L.; Probst, C.: ¬The delineation of an interdisciplinary specialty in terms of a journal set : the case of communication studies (2009) 0.01
```
0.010569612 = product of:
  0.031708833 = sum of:
    0.031708833 = product of:
      0.063417666 = sum of:
        0.063417666 = weight(_text_:methodology in 2952) [ClassicSimilarity], result of:
          0.063417666 = score(doc=2952,freq=2.0), product of:
            0.21236731 = queryWeight, product of:
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.047143444 = queryNorm
            0.29862255 = fieldWeight in 2952, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.046875 = fieldNorm(doc=2952)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)
```
Abstract

A journal set in an interdisciplinary or newly developing area can be determined by including the journals classified under the most relevant ISI Subject Categories into a journal-journal citation matrix. Despite the fuzzy character of borders, factor analysis of the citation patterns enables us to delineate the specific set by discarding the noise. This methodology is illustrated using communication studies as a hybrid development between political science and social psychology. The development can be visualized using animations which support the claim that a specific journal set in communication studies is increasingly developing, notably in the being cited patterns. The resulting set of 28 journals in communication studies is smaller and more focused than the 45 journals classified by the ISI Subject Categories as Communication. The proposed method is tested for its robustness by extending the relevant environments to sets including many more journals.

Leydesdorff, L.: ¬The construction and globalization of the knowledge base in inter-human communication systems (2003) 0.01

0.006387286 = product of:
  0.019161858 = sum of:
    0.019161858 = product of:
      0.038323715 = sum of:
        0.038323715 = weight(_text_:22 in 1621) [ClassicSimilarity], result of:
          0.038323715 = score(doc=1621,freq=2.0), product of:
            0.16508831 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.047143444 = queryNorm
            0.23214069 = fieldWeight in 1621, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=1621)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)

Date: 22. 5.2003 19:48:04

Leydesdorff, L.: Can networks of journal-journal citations be used as indicators of change in the social sciences? (2003) 0.01

0.006387286 = product of:
  0.019161858 = sum of:
    0.019161858 = product of:
      0.038323715 = sum of:
        0.038323715 = weight(_text_:22 in 4460) [ClassicSimilarity], result of:
          0.038323715 = score(doc=4460,freq=2.0), product of:
            0.16508831 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.047143444 = queryNorm
            0.23214069 = fieldWeight in 4460, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=4460)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)

Date: 6.11.2005 19:02:22

Leydesdorff, L.; Sun, Y.: National and international dimensions of the Triple Helix in Japan : university-industry-government versus international coauthorship relations (2009) 0.01

0.006387286 = product of:
  0.019161858 = sum of:
    0.019161858 = product of:
      0.038323715 = sum of:
        0.038323715 = weight(_text_:22 in 2761) [ClassicSimilarity], result of:
          0.038323715 = score(doc=2761,freq=2.0), product of:
            0.16508831 = queryWeight, product of:
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.047143444 = queryNorm
            0.23214069 = fieldWeight in 2761, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.5018296 = idf(docFreq=3622, maxDocs=44218)
              0.046875 = fieldNorm(doc=2761)
      0.5 = coord(1/2)
  0.33333334 = coord(1/3)

Date: 22. 3.2009 19:07:20

Search (7 results, page 1 of 1)

Authors

Types

Themes