Search (60 results, page 1 of 3)

  • × author_ss:"Egghe, L."
  1. Egghe, L.; Rousseau, R.: Introduction to informetrics : quantitative methods in library, documentation and information science (1990) 0.06
    0.056954324 = product of:
      0.23595363 = sum of:
        0.075655445 = weight(_text_:allgemeines in 1515) [ClassicSimilarity], result of:
          0.075655445 = score(doc=1515,freq=4.0), product of:
            0.12123675 = queryWeight, product of:
              5.705423 = idf(docFreq=399, maxDocs=44218)
              0.02124939 = queryNorm
            0.62403065 = fieldWeight in 1515, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              5.705423 = idf(docFreq=399, maxDocs=44218)
              0.0546875 = fieldNorm(doc=1515)
        0.050240368 = weight(_text_:buch in 1515) [ClassicSimilarity], result of:
          0.050240368 = score(doc=1515,freq=4.0), product of:
            0.09879628 = queryWeight, product of:
              4.64937 = idf(docFreq=1149, maxDocs=44218)
              0.02124939 = queryNorm
            0.5085249 = fieldWeight in 1515, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              4.64937 = idf(docFreq=1149, maxDocs=44218)
              0.0546875 = fieldNorm(doc=1515)
        0.011416892 = weight(_text_:und in 1515) [ClassicSimilarity], result of:
          0.011416892 = score(doc=1515,freq=4.0), product of:
            0.047096446 = queryWeight, product of:
              2.216367 = idf(docFreq=13101, maxDocs=44218)
              0.02124939 = queryNorm
            0.24241515 = fieldWeight in 1515, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              2.216367 = idf(docFreq=13101, maxDocs=44218)
              0.0546875 = fieldNorm(doc=1515)
        0.032656208 = product of:
          0.065312415 = sum of:
            0.065312415 = weight(_text_:bibliothekswesen in 1515) [ClassicSimilarity], result of:
              0.065312415 = score(doc=1515,freq=8.0), product of:
                0.09472281 = queryWeight, product of:
                  4.457672 = idf(docFreq=1392, maxDocs=44218)
                  0.02124939 = queryNorm
                0.68951094 = fieldWeight in 1515, product of:
                  2.828427 = tf(freq=8.0), with freq of:
                    8.0 = termFreq=8.0
                  4.457672 = idf(docFreq=1392, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1515)
          0.5 = coord(1/2)
        0.047162544 = weight(_text_:informationswissenschaft in 1515) [ClassicSimilarity], result of:
          0.047162544 = score(doc=1515,freq=4.0), product of:
            0.09572223 = queryWeight, product of:
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.02124939 = queryNorm
            0.4927021 = fieldWeight in 1515, product of:
              2.0 = tf(freq=4.0), with freq of:
                4.0 = termFreq=4.0
              4.504705 = idf(docFreq=1328, maxDocs=44218)
              0.0546875 = fieldNorm(doc=1515)
        0.008654194 = product of:
          0.025962582 = sum of:
            0.025962582 = weight(_text_:l in 1515) [ClassicSimilarity], result of:
              0.025962582 = score(doc=1515,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.30739886 = fieldWeight in 1515, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1515)
          0.33333334 = coord(1/3)
        0.010167964 = product of:
          0.020335928 = sum of:
            0.020335928 = weight(_text_:29 in 1515) [ClassicSimilarity], result of:
              0.020335928 = score(doc=1515,freq=2.0), product of:
                0.07474871 = queryWeight, product of:
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.02124939 = 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)
          0.5 = coord(1/2)
      0.2413793 = coord(7/29)
    
    Classification
    AN 70400 Allgemeines / Buch- und Bibliothekswesen, Informationswissenschaft / Bibliothekswesen / Bibliotheksverwaltung / Bibliotheksanalyse, -statistik
    Date
    29. 2.2008 19:02:46
    RVK
    AN 70400 Allgemeines / Buch- und Bibliothekswesen, Informationswissenschaft / Bibliothekswesen / Bibliotheksverwaltung / Bibliotheksanalyse, -statistik
  2. Egghe, L.: ¬A noninformetric analysis of the relationship between citation age and journal productivity (2001) 0.00
    0.0022999332 = product of:
      0.033349033 = sum of:
        0.00741788 = product of:
          0.02225364 = sum of:
            0.02225364 = weight(_text_:l in 5685) [ClassicSimilarity], result of:
              0.02225364 = score(doc=5685,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.26348472 = fieldWeight in 5685, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.046875 = fieldNorm(doc=5685)
          0.33333334 = coord(1/3)
        0.025931153 = sum of:
          0.008500358 = weight(_text_:1 in 5685) [ClassicSimilarity], result of:
            0.008500358 = score(doc=5685,freq=2.0), product of:
              0.05219918 = queryWeight, product of:
                2.4565027 = idf(docFreq=10304, maxDocs=44218)
                0.02124939 = queryNorm
              0.16284466 = fieldWeight in 5685, product of:
                1.4142135 = tf(freq=2.0), with freq of:
                  2.0 = termFreq=2.0
                2.4565027 = idf(docFreq=10304, maxDocs=44218)
                0.046875 = fieldNorm(doc=5685)
          0.017430795 = weight(_text_:29 in 5685) [ClassicSimilarity], result of:
            0.017430795 = score(doc=5685,freq=2.0), product of:
              0.07474871 = queryWeight, product of:
                3.5176873 = idf(docFreq=3565, maxDocs=44218)
                0.02124939 = 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)
      0.06896552 = coord(2/29)
    
    Abstract
    A problem, raised by Wallace (JASIS, 37,136-145,1986), on the relation between the journal's median citation age and its number of articles is studied. Leaving open the problem as such, we give a statistical explanation of this relationship, when replacing "median" by "mean" in Wallace's problem. The cloud of points, found by Wallace, is explained in this sense that the points are scattered over the area in first quadrant, limited by a curve of the form y=1 + E/x**2 where E is a constant. This curve is obtained by using the Central Limit Theorem in statistics and, hence, has no intrinsic informetric foundation. The article closes with some reflections on explanations of regularities in informetrics, based on statistical, probabilistic or informetric results, or on a combination thereof
    Date
    29. 9.2001 13:59:34
  3. Egghe, L.: Untangling Herdan's law and Heaps' law : mathematical and informetric arguments (2007) 0.00
    0.0021189654 = product of:
      0.030724999 = sum of:
        0.006181567 = product of:
          0.0185447 = sum of:
            0.0185447 = weight(_text_:l in 271) [ClassicSimilarity], result of:
              0.0185447 = score(doc=271,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.2195706 = fieldWeight in 271, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=271)
          0.33333334 = coord(1/3)
        0.02454343 = sum of:
          0.0100177685 = weight(_text_:1 in 271) [ClassicSimilarity], result of:
            0.0100177685 = score(doc=271,freq=4.0), product of:
              0.05219918 = queryWeight, product of:
                2.4565027 = idf(docFreq=10304, maxDocs=44218)
                0.02124939 = queryNorm
              0.19191428 = fieldWeight in 271, product of:
                2.0 = tf(freq=4.0), with freq of:
                  4.0 = termFreq=4.0
                2.4565027 = idf(docFreq=10304, maxDocs=44218)
                0.0390625 = fieldNorm(doc=271)
          0.014525663 = weight(_text_:29 in 271) [ClassicSimilarity], result of:
            0.014525663 = score(doc=271,freq=2.0), product of:
              0.07474871 = queryWeight, product of:
                3.5176873 = idf(docFreq=3565, maxDocs=44218)
                0.02124939 = 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)
      0.06896552 = coord(2/29)
    
    Abstract
    Herdan's law in linguistics and Heaps' law in information retrieval are different formulations of the same phenomenon. Stated briefly and in linguistic terms they state that vocabularies' sizes are concave increasing power laws of texts' sizes. This study investigates these laws from a purely mathematical and informetric point of view. A general informetric argument shows that the problem of proving these laws is, in fact, ill-posed. Using the more general terminology of sources and items, the author shows by presenting exact formulas from Lotkaian informetrics that the total number T of sources is not only a function of the total number A of items, but is also a function of several parameters (e.g., the parameters occurring in Lotka's law). Consequently, it is shown that a fixed T(or A) value can lead to different possible A (respectively, T) values. Limiting the T(A)-variability to increasing samples (e.g., in a text as done in linguistics) the author then shows, in a purely mathematical way, that for large sample sizes T~ A**phi, where phi is a constant, phi < 1 but close to 1, hence roughly, Heaps' or Herdan's law can be proved without using any linguistic or informetric argument. The author also shows that for smaller samples, a is not a constant but essentially decreases as confirmed by practical examples. Finally, an exact informetric argument on random sampling in the items shows that, in most cases, T= T(A) is a concavely increasing function, in accordance with practical examples.
    Date
    29. 4.2007 19:51:08
  4. Egghe, L.: ¬A universal method of information retrieval evaluation : the "missing" link M and the universal IR surface (2004) 0.00
    0.002100523 = product of:
      0.020305056 = sum of:
        0.00741788 = product of:
          0.02225364 = sum of:
            0.02225364 = weight(_text_:l in 2558) [ClassicSimilarity], result of:
              0.02225364 = score(doc=2558,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.26348472 = fieldWeight in 2558, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2558)
          0.33333334 = coord(1/3)
        0.004250179 = product of:
          0.008500358 = sum of:
            0.008500358 = weight(_text_:1 in 2558) [ClassicSimilarity], result of:
              0.008500358 = score(doc=2558,freq=2.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.16284466 = fieldWeight in 2558, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2558)
          0.5 = coord(1/2)
        0.008636996 = product of:
          0.017273992 = sum of:
            0.017273992 = weight(_text_:22 in 2558) [ClassicSimilarity], result of:
              0.017273992 = score(doc=2558,freq=2.0), product of:
                0.07441174 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.02124939 = 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)
          0.5 = coord(1/2)
      0.10344828 = coord(3/29)
    
    Date
    14. 8.2004 19:17:22
    Source
    Information processing and management. 40(2004) no.1, S.21-30
  5. Egghe, L.: Properties of the n-overlap vector and n-overlap similarity theory (2006) 0.00
    0.0019166112 = product of:
      0.027790863 = sum of:
        0.006181567 = product of:
          0.0185447 = sum of:
            0.0185447 = weight(_text_:l in 194) [ClassicSimilarity], result of:
              0.0185447 = score(doc=194,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.2195706 = fieldWeight in 194, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=194)
          0.33333334 = coord(1/3)
        0.021609295 = sum of:
          0.007083631 = weight(_text_:1 in 194) [ClassicSimilarity], result of:
            0.007083631 = score(doc=194,freq=2.0), product of:
              0.05219918 = queryWeight, product of:
                2.4565027 = idf(docFreq=10304, maxDocs=44218)
                0.02124939 = queryNorm
              0.13570388 = fieldWeight in 194, product of:
                1.4142135 = tf(freq=2.0), with freq of:
                  2.0 = termFreq=2.0
                2.4565027 = idf(docFreq=10304, maxDocs=44218)
                0.0390625 = fieldNorm(doc=194)
          0.014525663 = weight(_text_:29 in 194) [ClassicSimilarity], result of:
            0.014525663 = score(doc=194,freq=2.0), product of:
              0.07474871 = queryWeight, product of:
                3.5176873 = idf(docFreq=3565, maxDocs=44218)
                0.02124939 = 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)
      0.06896552 = coord(2/29)
    
    Abstract
    In the first part of this article the author defines the n-overlap vector whose coordinates consist of the fraction of the objects (e.g., books, N-grams, etc.) that belong to 1, 2, , n sets (more generally: families) (e.g., libraries, databases, etc.). With the aid of the Lorenz concentration theory, a theory of n-overlap similarity is conceived together with corresponding measures, such as the generalized Jaccard index (generalizing the well-known Jaccard index in case n 5 2). Next, the distributional form of the n-overlap vector is determined assuming certain distributions of the object's and of the set (family) sizes. In this section the decreasing power law and decreasing exponential distribution is explained for the n-overlap vector. Both item (token) n-overlap and source (type) n-overlap are studied. The n-overlap properties of objects indexed by a hierarchical system (e.g., books indexed by numbers from a UDC or Dewey system or by N-grams) are presented in the final section. The author shows how the results given in the previous section can be applied as well as how the Lorenz order of the n-overlap vector is respected by an increase or a decrease of the level of refinement in the hierarchical system (e.g., the value N in N-grams).
    Date
    3. 1.2007 14:26:29
  6. Egghe, L.: Empirical and combinatorial study of country occurrences in multi-authored papers (2006) 0.00
    0.0018681447 = product of:
      0.018058732 = sum of:
        0.004613121 = weight(_text_:und in 81) [ClassicSimilarity], result of:
          0.004613121 = score(doc=81,freq=2.0), product of:
            0.047096446 = queryWeight, product of:
              2.216367 = idf(docFreq=13101, maxDocs=44218)
              0.02124939 = queryNorm
            0.09795051 = fieldWeight in 81, product of:
              1.4142135 = tf(freq=2.0), with freq of:
                2.0 = termFreq=2.0
              2.216367 = idf(docFreq=13101, maxDocs=44218)
              0.03125 = fieldNorm(doc=81)
        0.0049452535 = product of:
          0.01483576 = sum of:
            0.01483576 = weight(_text_:l in 81) [ClassicSimilarity], result of:
              0.01483576 = score(doc=81,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.17565648 = fieldWeight in 81, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.03125 = fieldNorm(doc=81)
          0.33333334 = coord(1/3)
        0.008500358 = product of:
          0.017000716 = sum of:
            0.017000716 = weight(_text_:1 in 81) [ClassicSimilarity], result of:
              0.017000716 = score(doc=81,freq=18.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.32568932 = fieldWeight in 81, product of:
                  4.2426405 = tf(freq=18.0), with freq of:
                    18.0 = termFreq=18.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.03125 = fieldNorm(doc=81)
          0.5 = coord(1/2)
      0.10344828 = coord(3/29)
    
    Abstract
    Papers written by several authors can be classified according to the countries of the author affiliations. The empirical part of this paper consists of two datasets. One dataset consists of 1,035 papers retrieved via the search "pedagog*" in the years 2004 and 2005 (up to October) in Academic Search Elite which is a case where phi(m) = the number of papers with m =1, 2,3 ... authors is decreasing, hence most of the papers have a low number of authors. Here we find that #, m = the number of times a country occurs j times in a m-authored paper, j =1, ..., m-1 is decreasing and that # m, m is much higher than all the other #j, m values. The other dataset consists of 3,271 papers retrieved via the search "enzyme" in the year 2005 (up to October) in the same database which is a case of a non-decreasing phi(m): most papers have 3 or 4 authors and we even find many papers with a much higher number of authors. In this case we show again that # m, m is much higher than the other #j, m values but that #j, m is not decreasing anymore in j =1, ..., m-1, although #1, m is (apart from # m, m) the largest number amongst the #j,m. The combinatorial part gives a proof of the fact that #j,m decreases for j = 1, m-1, supposing that all cases are equally possible. This shows that the first dataset is more conform with this model than the second dataset. Explanations for these findings are given. From the data we also find the (we think: new) distribution of number of papers with n =1, 2,3,... countries (i.e. where there are n different countries involved amongst the m (a n) authors of a paper): a fast decreasing function e.g. as a power law with a very large Lotka exponent.
    Source
    Information - Wissenschaft und Praxis. 57(2006) H.8, S.427-432
  7. Egghe, L.; Guns, R.; Rousseau, R.; Leuven, K.U.: Erratum (2012) 0.00
    0.0018453882 = product of:
      0.026758129 = sum of:
        0.012363134 = product of:
          0.0370894 = sum of:
            0.0370894 = weight(_text_:l in 4992) [ClassicSimilarity], result of:
              0.0370894 = score(doc=4992,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.4391412 = fieldWeight in 4992, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.078125 = fieldNorm(doc=4992)
          0.33333334 = coord(1/3)
        0.014394995 = product of:
          0.02878999 = sum of:
            0.02878999 = weight(_text_:22 in 4992) [ClassicSimilarity], result of:
              0.02878999 = score(doc=4992,freq=2.0), product of:
                0.07441174 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.02124939 = 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)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Date
    14. 2.2012 12:53:22
  8. Egghe, L.: ¬The Hirsch index and related impact measures (2010) 0.00
    0.0016093875 = product of:
      0.023336118 = sum of:
        0.01483576 = product of:
          0.04450728 = sum of:
            0.04450728 = weight(_text_:l in 1597) [ClassicSimilarity], result of:
              0.04450728 = score(doc=1597,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.52696943 = fieldWeight in 1597, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.09375 = fieldNorm(doc=1597)
          0.33333334 = coord(1/3)
        0.008500358 = product of:
          0.017000716 = sum of:
            0.017000716 = weight(_text_:1 in 1597) [ClassicSimilarity], result of:
              0.017000716 = score(doc=1597,freq=2.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.32568932 = fieldWeight in 1597, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.09375 = fieldNorm(doc=1597)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Source
    Annual review of information science and technology. 44(2010) no.1, S.65-114
  9. Egghe, L.: Existence theorem of the quadruple (P, R, F, M) : precision, recall, fallout and miss (2007) 0.00
    0.0015525371 = product of:
      0.022511788 = sum of:
        0.010490468 = product of:
          0.0314714 = sum of:
            0.0314714 = weight(_text_:l in 2011) [ClassicSimilarity], result of:
              0.0314714 = score(doc=2011,freq=4.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.37262368 = fieldWeight in 2011, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2011)
          0.33333334 = coord(1/3)
        0.012021321 = product of:
          0.024042642 = sum of:
            0.024042642 = weight(_text_:1 in 2011) [ClassicSimilarity], result of:
              0.024042642 = score(doc=2011,freq=16.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.46059424 = fieldWeight in 2011, product of:
                  4.0 = tf(freq=16.0), with freq of:
                    16.0 = termFreq=16.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.046875 = fieldNorm(doc=2011)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Abstract
    In an earlier paper [Egghe, L. (2004). A universal method of information retrieval evaluation: the "missing" link M and the universal IR surface. Information Processing and Management, 40, 21-30] we showed that, given an IR system, and if P denotes precision, R recall, F fallout and M miss (re-introduced in the paper mentioned above), we have the following relationship between P, R, F and M: P/(1-P)*(1-R)/R*F/(1-F)*(1-M)/M = 1. In this paper we prove the (more difficult) converse: given any four rational numbers in the interval ]0, 1[ satisfying the above equation, then there exists an IR system such that these four numbers (in any order) are the precision, recall, fallout and miss of this IR system. As a consequence we show that any three rational numbers in ]0, 1[ represent any three measures taken from precision, recall, fallout and miss of a certain IR system. We also show that this result is also true for two numbers instead of three.
    Source
    Information processing and management. 43(2007) no.1, S.265-272
  10. Egghe, L.; Liang, L.; Rousseau, R.: Fundamental properties of rhythm sequences (2008) 0.00
    0.0014363673 = product of:
      0.020827325 = sum of:
        0.012238878 = product of:
          0.036716633 = sum of:
            0.036716633 = weight(_text_:l in 1965) [ClassicSimilarity], result of:
              0.036716633 = score(doc=1965,freq=4.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.4347276 = fieldWeight in 1965, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1965)
          0.33333334 = coord(1/3)
        0.008588447 = product of:
          0.017176894 = sum of:
            0.017176894 = weight(_text_:1 in 1965) [ClassicSimilarity], result of:
              0.017176894 = score(doc=1965,freq=6.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.32906446 = fieldWeight in 1965, product of:
                  2.4494898 = tf(freq=6.0), with freq of:
                    6.0 = termFreq=6.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1965)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Abstract
    Fundamental mathematical properties of rhythm sequences are studied. In particular, a set of three axioms for valid rhythm indicators is proposed, and it is shown that the R-indicator satisfies only two out of three but that the R-indicator satisfies all three. This fills a critical, logical gap in the study of these indicator sequences. Matrices leading to a constant R-sequence are called baseline matrices. They are characterized as matrices with constant w-year diachronous impact factors. The relation with classical impact factors is clarified. Using regression analysis matrices with a rhythm sequence that is on average equal to 1 (smaller than 1, larger than 1) are characterized.
  11. Egghe, L.: Influence of adding or deleting items and sources on the h-index (2010) 0.00
    0.0011126399 = product of:
      0.016133279 = sum of:
        0.00741788 = product of:
          0.02225364 = sum of:
            0.02225364 = weight(_text_:l in 3336) [ClassicSimilarity], result of:
              0.02225364 = score(doc=3336,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.26348472 = fieldWeight in 3336, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.046875 = fieldNorm(doc=3336)
          0.33333334 = coord(1/3)
        0.008715398 = product of:
          0.017430795 = sum of:
            0.017430795 = weight(_text_:29 in 3336) [ClassicSimilarity], result of:
              0.017430795 = score(doc=3336,freq=2.0), product of:
                0.07474871 = queryWeight, product of:
                  3.5176873 = idf(docFreq=3565, maxDocs=44218)
                  0.02124939 = 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)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Date
    31. 5.2010 15:02:29
  12. Egghe, L.; Rousseau, R.: Averaging and globalising quotients of informetric and scientometric data (1996) 0.00
    0.0011072329 = product of:
      0.016054876 = sum of:
        0.00741788 = product of:
          0.02225364 = sum of:
            0.02225364 = weight(_text_:l in 7659) [ClassicSimilarity], result of:
              0.02225364 = score(doc=7659,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.26348472 = fieldWeight in 7659, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.046875 = fieldNorm(doc=7659)
          0.33333334 = coord(1/3)
        0.008636996 = product of:
          0.017273992 = sum of:
            0.017273992 = weight(_text_:22 in 7659) [ClassicSimilarity], result of:
              0.017273992 = score(doc=7659,freq=2.0), product of:
                0.07441174 = queryWeight, product of:
                  3.5018296 = idf(docFreq=3622, maxDocs=44218)
                  0.02124939 = 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)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Source
    Journal of information science. 22(1996) no.3, S.165-170
  13. Egghe, L.: Theory of the topical coverage of multiple databases (2013) 0.00
    0.0010804574 = product of:
      0.015666632 = sum of:
        0.008654194 = product of:
          0.025962582 = sum of:
            0.025962582 = weight(_text_:l in 526) [ClassicSimilarity], result of:
              0.025962582 = score(doc=526,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.30739886 = fieldWeight in 526, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=526)
          0.33333334 = coord(1/3)
        0.0070124376 = product of:
          0.014024875 = sum of:
            0.014024875 = weight(_text_:1 in 526) [ClassicSimilarity], result of:
              0.014024875 = score(doc=526,freq=4.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.26867998 = fieldWeight in 526, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=526)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Abstract
    We present a model that describes which fraction of the literature on a certain topic we will find when we use n (n = 1, 2, .) databases. It is a generalization of the theory of discovering usability problems. We prove that, in all practical cases, this fraction is a concave function of n, the number of used databases, thereby explaining some graphs that exist in the literature. We also study limiting features of this fraction for n very high and we characterize the case that we find all literature on a certain topic for n high enough.
    Source
    Journal of the American Society for Information Science and Technology. 64(2013) no.1, S.126-131
  14. Egghe, L.: ¬The amount of actions needed for shelving and reshelving (1996) 0.00
    0.0010729249 = product of:
      0.015557412 = sum of:
        0.009890507 = product of:
          0.02967152 = sum of:
            0.02967152 = weight(_text_:l in 4394) [ClassicSimilarity], result of:
              0.02967152 = score(doc=4394,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.35131297 = fieldWeight in 4394, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0625 = fieldNorm(doc=4394)
          0.33333334 = coord(1/3)
        0.005666905 = product of:
          0.01133381 = sum of:
            0.01133381 = weight(_text_:1 in 4394) [ClassicSimilarity], result of:
              0.01133381 = score(doc=4394,freq=2.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.2171262 = fieldWeight in 4394, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0625 = fieldNorm(doc=4394)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Source
    Library management. 17(1996) no.1, S.18-24
  15. Egghe, L.: Mathematical theories of citation (1998) 0.00
    0.0010729249 = product of:
      0.015557412 = sum of:
        0.009890507 = product of:
          0.02967152 = sum of:
            0.02967152 = weight(_text_:l in 5125) [ClassicSimilarity], result of:
              0.02967152 = score(doc=5125,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.35131297 = fieldWeight in 5125, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0625 = fieldNorm(doc=5125)
          0.33333334 = coord(1/3)
        0.005666905 = product of:
          0.01133381 = sum of:
            0.01133381 = weight(_text_:1 in 5125) [ClassicSimilarity], result of:
              0.01133381 = score(doc=5125,freq=2.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.2171262 = fieldWeight in 5125, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0625 = fieldNorm(doc=5125)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Source
    Scientometrics. 43(1998) no.1, S.57-62
  16. Egghe, L.: Vector retrieval, fuzzy retrieval and the universal fuzzy IR surface for IR evaluation (2004) 0.00
    9.3880936E-4 = product of:
      0.013612736 = sum of:
        0.008654194 = product of:
          0.025962582 = sum of:
            0.025962582 = weight(_text_:l in 2531) [ClassicSimilarity], result of:
              0.025962582 = score(doc=2531,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.30739886 = fieldWeight in 2531, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=2531)
          0.33333334 = coord(1/3)
        0.0049585416 = product of:
          0.009917083 = sum of:
            0.009917083 = weight(_text_:1 in 2531) [ClassicSimilarity], result of:
              0.009917083 = score(doc=2531,freq=2.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.18998542 = fieldWeight in 2531, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=2531)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Abstract
    It is shown that vector information retrieval (IR) and general fuzzy IR uses two types of fuzzy set operations: the original "Zadeh min-max operations" and the so-called "probabilistic sum and algebraic product operations". The universal IR surface, valid for classical 0-1 IR (i.e. where ordinary sets are used) and used in IR evaluation, is extended to and reproved for vector IR, using the probabilistic sum and algebraic product model. We also show (by counterexample) that, using the "Zadeh min-max" fuzzy model, yields a breakdown of this IR surface.
  17. Egghe, L.: ¬The influence of transformations on the h-index and the g-index (2008) 0.00
    9.3880936E-4 = product of:
      0.013612736 = sum of:
        0.008654194 = product of:
          0.025962582 = sum of:
            0.025962582 = weight(_text_:l in 1881) [ClassicSimilarity], result of:
              0.025962582 = score(doc=1881,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.30739886 = fieldWeight in 1881, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1881)
          0.33333334 = coord(1/3)
        0.0049585416 = product of:
          0.009917083 = sum of:
            0.009917083 = weight(_text_:1 in 1881) [ClassicSimilarity], result of:
              0.009917083 = score(doc=1881,freq=2.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.18998542 = fieldWeight in 1881, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0546875 = fieldNorm(doc=1881)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Date
    1. 6.2008 12:58:41
  18. Egghe, L.; Guns, R.: Applications of the generalized law of Benford to informetric data (2012) 0.00
    9.2610624E-4 = product of:
      0.013428541 = sum of:
        0.00741788 = product of:
          0.02225364 = sum of:
            0.02225364 = weight(_text_:l in 376) [ClassicSimilarity], result of:
              0.02225364 = score(doc=376,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.26348472 = fieldWeight in 376, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.046875 = fieldNorm(doc=376)
          0.33333334 = coord(1/3)
        0.0060106604 = product of:
          0.012021321 = sum of:
            0.012021321 = weight(_text_:1 in 376) [ClassicSimilarity], result of:
              0.012021321 = score(doc=376,freq=4.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.23029712 = fieldWeight in 376, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.046875 = fieldNorm(doc=376)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Abstract
    In a previous work (Egghe, 2011), the first author showed that Benford's law (describing the logarithmic distribution of the numbers 1, 2, ... , 9 as first digits of data in decimal form) is related to the classical law of Zipf with exponent 1. The work of Campanario and Coslado (2011), however, shows that Benford's law does not always fit practical data in a statistical sense. In this article, we use a generalization of Benford's law related to the general law of Zipf with exponent ? > 0. Using data from Campanario and Coslado, we apply nonlinear least squares to determine the optimal ? and show that this generalized law of Benford fits the data better than the classical law of Benford.
  19. 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
    8.4939116E-4 = product of:
      0.012316172 = sum of:
        0.006181567 = product of:
          0.0185447 = sum of:
            0.0185447 = weight(_text_:l in 2009) [ClassicSimilarity], result of:
              0.0185447 = score(doc=2009,freq=2.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.2195706 = fieldWeight in 2009, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=2009)
          0.33333334 = coord(1/3)
        0.006134605 = product of:
          0.01226921 = sum of:
            0.01226921 = weight(_text_:1 in 2009) [ClassicSimilarity], result of:
              0.01226921 = score(doc=2009,freq=6.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.23504603 = fieldWeight in 2009, product of:
                  2.4494898 = tf(freq=6.0), with freq of:
                    6.0 = termFreq=6.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=2009)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    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.
  20. Egghe, L.: Mathematical study of h-index sequences (2009) 0.00
    8.471635E-4 = product of:
      0.012283871 = sum of:
        0.008742056 = product of:
          0.026226167 = sum of:
            0.026226167 = weight(_text_:l in 4217) [ClassicSimilarity], result of:
              0.026226167 = score(doc=4217,freq=4.0), product of:
                0.08445894 = queryWeight, product of:
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.02124939 = queryNorm
                0.31051973 = fieldWeight in 4217, product of:
                  2.0 = tf(freq=4.0), with freq of:
                    4.0 = termFreq=4.0
                  3.9746525 = idf(docFreq=2257, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=4217)
          0.33333334 = coord(1/3)
        0.0035418156 = product of:
          0.007083631 = sum of:
            0.007083631 = weight(_text_:1 in 4217) [ClassicSimilarity], result of:
              0.007083631 = score(doc=4217,freq=2.0), product of:
                0.05219918 = queryWeight, product of:
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.02124939 = queryNorm
                0.13570388 = fieldWeight in 4217, product of:
                  1.4142135 = tf(freq=2.0), with freq of:
                    2.0 = termFreq=2.0
                  2.4565027 = idf(docFreq=10304, maxDocs=44218)
                  0.0390625 = fieldNorm(doc=4217)
          0.5 = coord(1/2)
      0.06896552 = coord(2/29)
    
    Abstract
    This paper studies mathematical properties of h-index sequences as developed by Liang [Liang, L. (2006). h-Index sequence and h-index matrix: Constructions and applications. Scientometrics, 69(1), 153-159]. For practical reasons, Liming studies such sequences where the time goes backwards while it is more logical to use the time going forward (real career periods). Both type of h-index sequences are studied here and their interrelations are revealed. We show cases where these sequences are convex, linear and concave. We also show that, when one of the sequences is convex then the other one is concave, showing that the reverse-time sequence, in general, cannot be used to derive similar properties of the (difficult to obtain) forward time sequence. We show that both sequences are the same if and only if the author produces the same number of papers per year. If the author produces an increasing number of papers per year, then Liang's h-sequences are above the "normal" ones. All these results are also valid for g- and R-sequences. The results are confirmed by the h-, g- and R-sequences (forward and reverse time) of the author.