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The Z-index: A geometric representation of productivity and impact which accounts for information in the entire rank-citation profile

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  • Petersen, Alexander M.
  • Succi, Sauro

Abstract

We present a simple generalization of Hirsch's h-index, Z≡h2+C/5, where C is the total number of citations. Z is aimed at correcting the potentially excessive penalty made by h on a scientist's highly cited papers, because for the majority of scientists analyzed, we find the excess citation fraction (C−h2)/C to be distributed closely around the value 0.75, meaning that 75% of the author's impact is neglected. Additionally, Z is less sensitive to local changes in a scientist's citation profile, namely perturbations which increase h while only marginally affecting C. Using real career data for 476 physicists careers and 488 biologist careers, we analyze both the distribution of Z and the rank stability of Z with respect to the Hirsch index h and the Egghe index g. We analyze careers distributed across a wide range of total impact, including top-cited physicists and biologists for benchmark comparison. In practice, the Z-index requires the same information needed to calculate h and could be effortlessly incorporated within career profile databases, such as Google Scholar and ResearcherID. Because Z incorporates information from the entire publication profile while being more robust than h and g to local perturbations, we argue that Z is better suited for ranking comparisons in academic decision-making scenarios comprising a large number of scientists.

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  • Petersen, Alexander M. & Succi, Sauro, 2013. "The Z-index: A geometric representation of productivity and impact which accounts for information in the entire rank-citation profile," Journal of Informetrics, Elsevier, vol. 7(4), pages 823-832.
  • Handle: RePEc:eee:infome:v:7:y:2013:i:4:p:823-832
    DOI: 10.1016/j.joi.2013.07.003
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    References listed on IDEAS

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    1. Bornmann, Lutz & Mutz, Rüdiger & Hug, Sven E. & Daniel, Hans-Dieter, 2011. "A multilevel meta-analysis of studies reporting correlations between the h index and 37 different h index variants," Journal of Informetrics, Elsevier, vol. 5(3), pages 346-359.
    2. Lutz Bornmann & Rüdiger Mutz & Hans‐Dieter Daniel, 2008. "Are there better indices for evaluation purposes than the h index? A comparison of nine different variants of the h index using data from biomedicine," Journal of the American Society for Information Science and Technology, Association for Information Science & Technology, vol. 59(5), pages 830-837, March.
    3. A. M. Petersen & O. Penner & H. E. Stanley, 2011. "Methods for detrending success metrics to account for inflationary and deflationary factors," The European Physical Journal B: Condensed Matter and Complex Systems, Springer;EDP Sciences, vol. 79(1), pages 67-78, January.
    4. Pablo D. Batista & Mônica G. Campiteli & Osame Kinouchi, 2006. "Is it possible to compare researchers with different scientific interests?," Scientometrics, Springer;Akadémiai Kiadó, vol. 68(1), pages 179-189, July.
    5. Filippo Radicchi & Claudio Castellano, 2013. "Analysis of bibliometric indicators for individual scholars in a large data set," Scientometrics, Springer;Akadémiai Kiadó, vol. 97(3), pages 627-637, December.
    6. Chun-Ting Zhang, 2010. "Relationship of the h-index, g-index, and e-index," Journal of the Association for Information Science & Technology, Association for Information Science & Technology, vol. 61(3), pages 625-628, March.
    7. Lutz Bornmann & Hans‐Dieter Daniel, 2007. "What do we know about the h index?," Journal of the American Society for Information Science and Technology, Association for Information Science & Technology, vol. 58(9), pages 1381-1385, July.
    8. Filippo Radicchi & Claudio Castellano, 2012. "A Reverse Engineering Approach to the Suppression of Citation Biases Reveals Universal Properties of Citation Distributions," PLOS ONE, Public Library of Science, vol. 7(3), pages 1-9, March.
    9. Radicchi, Filippo & Castellano, Claudio, 2012. "Testing the fairness of citation indicators for comparison across scientific domains: The case of fractional citation counts," Journal of Informetrics, Elsevier, vol. 6(1), pages 121-130.
    10. Naumis, G.G. & Cocho, G., 2008. "Tail universalities in rank distributions as an algebraic problem: The beta-like function," Physica A: Statistical Mechanics and its Applications, Elsevier, vol. 387(1), pages 84-96.
    11. Waltman, L. & van Eck, N.J.P., 2009. "A simple alternative to the h-index," ERIM Report Series Research in Management ERS-2009-043-LIS, Erasmus Research Institute of Management (ERIM), ERIM is the joint research institute of the Rotterdam School of Management, Erasmus University and the Erasmus School of Economics (ESE) at Erasmus University Rotterdam.
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    2. Oscar Fontanelli & Pedro Miramontes & Yaning Yang & Germinal Cocho & Wentian Li, 2016. "Beyond Zipf’s Law: The Lavalette Rank Function and Its Properties," PLOS ONE, Public Library of Science, vol. 11(9), pages 1-14, September.
    3. Letchford, Adrian & Preis, Tobias & Moat, Helen Susannah, 2016. "The advantage of simple paper abstracts," Journal of Informetrics, Elsevier, vol. 10(1), pages 1-8.
    4. Fabio Zagonari, 2019. "Scientific Production and Productivity for Characterizing an Author’s Publication History: Simple and Nested Gini’s and Hirsch’s Indexes Combined," Publications, MDPI, vol. 7(2), pages 1-30, May.

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