Search (10 results, page 1 of 1)

  • × author_ss:"Egghe, L."
  1. Egghe, L.: ¬A rationale for the Hirsch-index rank-order distribution and a comparison with the impact factor rank-order distribution (2009) 0.02
    0.018176163 = product of:
      0.18176162 = sum of:
        0.18176162 = weight(_text_:log in 3124) [ClassicSimilarity], result of:
          0.18176162 = score(doc=3124,freq=8.0), product of:
            0.18335998 = queryWeight, product of:
              6.4086204 = idf(docFreq=197, maxDocs=44218)
              0.028611459 = queryNorm
            0.99128294 = fieldWeight in 3124, product of:
              2.828427 = tf(freq=8.0), with freq of:
                8.0 = termFreq=8.0
              6.4086204 = idf(docFreq=197, maxDocs=44218)
              0.0546875 = fieldNorm(doc=3124)
      0.1 = coord(1/10)
    
    Abstract
    We present a rationale for the Hirsch-index rank-order distribution and prove that it is a power law (hence a straight line in the log-log scale). This is confirmed by experimental data of Pyykkö and by data produced in this article on 206 mathematics journals. This distribution is of a completely different nature than the impact factor (IF) rank-order distribution which (as proved in a previous article) is S-shaped. This is also confirmed by our example. Only in the log-log scale of the h-index distribution do we notice a concave deviation of the straight line for higher ranks. This phenomenon is discussed.
  2. Egghe, L.; Ravichandra Rao, I.K.: ¬The influence of the broadness of a query of a topic on its h-index : models and examples of the h-index of n-grams (2008) 0.00
    0.0016833913 = product of:
      0.016833913 = sum of:
        0.016833913 = weight(_text_:web in 2009) [ClassicSimilarity], result of:
          0.016833913 = score(doc=2009,freq=2.0), product of:
            0.0933738 = queryWeight, product of:
              3.2635105 = idf(docFreq=4597, maxDocs=44218)
              0.028611459 = queryNorm
            0.18028519 = fieldWeight in 2009, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              3.2635105 = idf(docFreq=4597, maxDocs=44218)
              0.0390625 = fieldNorm(doc=2009)
      0.1 = coord(1/10)
    
    Abstract
    The article studies the influence of the query formulation of a topic on its h-index. In order to generate pure random sets of documents, we used N-grams (N variable) to measure this influence: strings of zeros, truncated at the end. The used databases are WoS and Scopus. The formula h=T**1/alpha, proved in Egghe and Rousseau (2006) where T is the number of retrieved documents and is Lotka's exponent, is confirmed being a concavely increasing function of T. We also give a formula for the relation between h and N the length of the N-gram: h=D10**(-N/alpha) where D is a constant, a convexly decreasing function, which is found in our experiments. Nonlinear regression on h=T**1/alpha gives an estimation of , which can then be used to estimate the h-index of the entire database (Web of Science [WoS] and Scopus): h=S**1/alpha, , where S is the total number of documents in the database.
  3. Egghe, L.; Guns, R.; Rousseau, R.; Leuven, K.U.: Erratum (2012) 0.00
    0.0012921527 = product of:
      0.012921526 = sum of:
        0.012921526 = product of:
          0.038764577 = sum of:
            0.038764577 = weight(_text_:22 in 4992) [ClassicSimilarity], result of:
              0.038764577 = score(doc=4992,freq=2.0), product of:
                0.10019246 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.028611459 = queryNorm
                0.38690117 = fieldWeight in 4992, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.078125 = fieldNorm(doc=4992)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Date
    14. 2.2012 12:53:22
  4. Egghe, L.; Rousseau, R.: Introduction to informetrics : quantitative methods in library, documentation and information science (1990) 0.00
    9.1271737E-4 = product of:
      0.009127174 = sum of:
        0.009127174 = product of:
          0.027381519 = sum of:
            0.027381519 = weight(_text_:29 in 1515) [ClassicSimilarity], result of:
              0.027381519 = score(doc=1515,freq=2.0), product of:
                0.10064617 = queryWeight, product of:
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.028611459 = queryNorm
                0.27205724 = fieldWeight in 1515, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1515)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Date
    29. 2.2008 19:02:46
  5. Egghe, L.: ¬A noninformetric analysis of the relationship between citation age and journal productivity (2001) 0.00
    7.823291E-4 = product of:
      0.007823291 = sum of:
        0.007823291 = product of:
          0.023469873 = sum of:
            0.023469873 = weight(_text_:29 in 5685) [ClassicSimilarity], result of:
              0.023469873 = score(doc=5685,freq=2.0), product of:
                0.10064617 = queryWeight, product of:
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.028611459 = queryNorm
                0.23319192 = fieldWeight in 5685, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.046875 = fieldNorm(doc=5685)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Date
    29. 9.2001 13:59:34
  6. Egghe, L.: Influence of adding or deleting items and sources on the h-index (2010) 0.00
    7.823291E-4 = product of:
      0.007823291 = sum of:
        0.007823291 = product of:
          0.023469873 = sum of:
            0.023469873 = weight(_text_:29 in 3336) [ClassicSimilarity], result of:
              0.023469873 = score(doc=3336,freq=2.0), product of:
                0.10064617 = queryWeight, product of:
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.028611459 = queryNorm
                0.23319192 = fieldWeight in 3336, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.046875 = fieldNorm(doc=3336)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Date
    31. 5.2010 15:02:29
  7. Egghe, L.; Rousseau, R.: Averaging and globalising quotients of informetric and scientometric data (1996) 0.00
    7.752915E-4 = product of:
      0.0077529154 = sum of:
        0.0077529154 = product of:
          0.023258746 = sum of:
            0.023258746 = weight(_text_:22 in 7659) [ClassicSimilarity], result of:
              0.023258746 = score(doc=7659,freq=2.0), product of:
                0.10019246 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.028611459 = queryNorm
                0.23214069 = fieldWeight in 7659, 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=7659)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Source
    Journal of information science. 22(1996) no.3, S.165-170
  8. Egghe, L.: ¬A universal method of information retrieval evaluation : the "missing" link M and the universal IR surface (2004) 0.00
    7.752915E-4 = product of:
      0.0077529154 = sum of:
        0.0077529154 = product of:
          0.023258746 = sum of:
            0.023258746 = weight(_text_:22 in 2558) [ClassicSimilarity], result of:
              0.023258746 = score(doc=2558,freq=2.0), product of:
                0.10019246 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.028611459 = queryNorm
                0.23214069 = fieldWeight in 2558, 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=2558)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Date
    14. 8.2004 19:17:22
  9. Egghe, L.: Properties of the n-overlap vector and n-overlap similarity theory (2006) 0.00
    6.51941E-4 = product of:
      0.00651941 = sum of:
        0.00651941 = product of:
          0.019558229 = sum of:
            0.019558229 = weight(_text_:29 in 194) [ClassicSimilarity], result of:
              0.019558229 = score(doc=194,freq=2.0), product of:
                0.10064617 = queryWeight, product of:
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.028611459 = queryNorm
                0.19432661 = fieldWeight in 194, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=194)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Date
    3. 1.2007 14:26:29
  10. Egghe, L.: Untangling Herdan's law and Heaps' law : mathematical and informetric arguments (2007) 0.00
    6.51941E-4 = product of:
      0.00651941 = sum of:
        0.00651941 = product of:
          0.019558229 = sum of:
            0.019558229 = weight(_text_:29 in 271) [ClassicSimilarity], result of:
              0.019558229 = score(doc=271,freq=2.0), product of:
                0.10064617 = queryWeight, product of:
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.028611459 = queryNorm
                0.19432661 = fieldWeight in 271, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=271)
          0.33333334 = coord(1/3)
      0.1 = coord(1/10)
    
    Date
    29. 4.2007 19:51:08