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  • × author_ss:"Leydesdorff, L."
  1. Ye, F.Y.; Leydesdorff, L.: ¬The "academic trace" of the performance matrix : a mathematical synthesis of the h-index and the integrated impact indicator (I3) (2014) 0.03 
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    Abstract
    The h-index provides us with 9 natural classes which can be written as a matrix of 3 vectors. The 3 vectors are: X = (X1, X2, X3) and indicates publication distribution in the h-core, the h-tail, and the uncited ones, respectively; Y = (Y1, Y2, Y3) denotes the citation distribution of the h-core, the h-tail and the so-called "excess" citations (above the h-threshold), respectively; and Z = (Z1, Z2, Z3) = (Y1-X1, Y2-X2, Y3-X3). The matrix V = (X,Y,Z)T constructs a measure of academic performance, in which the 9 numbers can all be provided with meanings in different dimensions. The "academic trace" tr(V) of this matrix follows naturally, and contributes a unique indicator for total academic achievements by summarizing and weighting the accumulation of publications and citations. This measure can also be used to combine the advantages of the h-index and the integrated impact indicator (I3) into a single number with a meaningful interpretation of the values. We illustrate the use of tr(V) for the cases of 2 journal sets, 2 universities, and ourselves as 2 individual authors.
  2. Leydesdorff, L.; Moya-Anegón, F. de; Nooy, W. de: Aggregated journal-journal citation relations in scopus and web of science matched and compared in terms of networks, maps, and interactive overlays (2016) 0.01 
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  3. Leydesdorff, L.; Radicchi, F.; Bornmann, L.; Castellano, C.; Nooy, W. de: Field-normalized impact factors (IFs) : a comparison of rescaling and fractionally counted IFs (2013) 0.01 
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  4. Leydesdorff, L.; Moya-Anegón, F. de; Guerrero-Bote, V.P.: Journal maps, interactive overlays, and the measurement of interdisciplinarity on the basis of Scopus data (1996-2012) (2015) 0.01 
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  5. Leydesdorff, L.; Nooy, W. de: Can "hot spots" in the sciences be mapped using the dynamics of aggregated journal-journal citation relations (2017) 0.01 
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  6. Leydesdorff, L.: ¬The construction and globalization of the knowledge base in inter-human communication systems (2003) 0.01 
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    Date
    22. 5.2003 19:48:04
  7. Leydesdorff, L.: Can networks of journal-journal citations be used as indicators of change in the social sciences? (2003) 0.01 
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    Date
    6.11.2005 19:02:22
  8. Leydesdorff, L.; Sun, Y.: National and international dimensions of the Triple Helix in Japan : university-industry-government versus international coauthorship relations (2009) 0.01 
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    Date
    22. 3.2009 19:07:20
  9. Leydesdorff, L.; Bornmann, L.; Wagner, C.S.: ¬The relative influences of government funding and international collaboration on citation impact (2019) 0.01 
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    Date
    8. 1.2019 18:22:45
  10. Leydesdorff, L.; Bornmann, L.: How fractional counting of citations affects the impact factor : normalization in terms of differences in citation potentials among fields of science (2011) 0.00 
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    Date
    22. 1.2011 12:51:07
  11. Hellsten, I.; Leydesdorff, L.: ¬The construction of interdisciplinarity : the development of the knowledge base and programmatic focus of the journal Climatic Change, 1977-2013 (2016) 0.00 
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    Date
    24. 8.2016 17:53:22
  12. Leydesdorff, L.; Johnson, M.W.; Ivanova, I.: Toward a calculus of redundancy : signification, codification, and anticipation in cultural evolution (2018) 0.00 
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    Date
    29. 9.2018 11:22:09

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