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Mean values of skewed distributions in the bibliometric assessment of research units

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  • Ulrich Schmoch

    (Fraunhofer ISI)

Abstract

Nearly all distributions in bibliometrics are skewed. In particular, the distribution of citations of publications by research units is skewed. In a statistical view, the calculation of mean values can imply misleading or even wrong information. However, in citation analysis, the calculation of mean values of skewed distributions are standard. Therefore, when ranking research units, it is recommended instead to replace the calculation of standard mean values by the calculation of adjusted mean values to exclude outliers with very high citations and those with very few or no citations as well. Such an adjusted mean value is oriented on the standard activity of a research unit and results in a more adequate assessment. This approach is based on the Hirsch-index concept. The calculation results in a different ranking of research units, which may be important in cases where the distribution of finances depends on bibliometric rankings. In addition, a differentiation between standard activities and excellent results is possible, thus opening two dimensions of the assessment of research units.

Suggested Citation

  • Ulrich Schmoch, 2020. "Mean values of skewed distributions in the bibliometric assessment of research units," Scientometrics, Springer;Akadémiai Kiadó, vol. 125(2), pages 925-935, November.
    • Handle: RePEc:spr:scient:v:125:y:2020:i:2:d:10.1007_s11192-020-03476-8
    DOI: 10.1007/s11192-020-03476-8
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    References listed on IDEAS

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    1. Pedro Albarrán & Juan A. Crespo & Ignacio Ortuño & Javier Ruiz-Castillo, 2011. "The skewness of science in 219 sub-fields and a number of aggregates," Scientometrics, Springer;Akadémiai Kiadó, vol. 88(2), pages 385-397, August.
    2. Pedro Albarrán & Javier Ruiz‐Castillo, 2011. "References made and citations received by scientific articles," Journal of the American Society for Information Science and Technology, Association for Information Science & Technology, vol. 62(1), pages 40-49, January.
    3. Loet Leydesdorff & Lutz Bornmann, 2011. "Integrated impact indicators compared with impact factors: An alternative research design with policy implications," Journal of the American Society for Information Science and Technology, Association for Information Science & Technology, vol. 62(11), pages 2133-2146, November.
    4. Opthof, Tobias & Leydesdorff, Loet, 2010. "Caveats for the journal and field normalizations in the CWTS (“Leiden”) evaluations of research performance," Journal of Informetrics, Elsevier, vol. 4(3), pages 423-430.
    5. Ulrich Schmoch & Bernd Beckert & Petra Schaper-Rinkel, 2019. "Impact assessment of a support programme of science-based emerging technologies," Scientometrics, Springer;Akadémiai Kiadó, vol. 118(3), pages 1141-1161, March.
    6. Costas, Rodrigo & Bordons, María, 2007. "The h-index: Advantages, limitations and its relation with other bibliometric indicators at the micro level," Journal of Informetrics, Elsevier, vol. 1(3), pages 193-203.
    7. Derek De Solla Price, 1976. "A general theory of bibliometric and other cumulative advantage processes," Journal of the American Society for Information Science, Association for Information Science & Technology, vol. 27(5), pages 292-306, September.
    8. Per O. Seglen, 1992. "The skewness of science," Journal of the American Society for Information Science, Association for Information Science & Technology, vol. 43(9), pages 628-638, October.
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    Cited by:

    1. Jaime A. Teixeira da Silva, 2021. "The i100-index, i1000-index and i10,000-index: expansion and fortification of the Google Scholar h-index for finer-scale citation descriptions and researcher classification," Scientometrics, Springer;Akadémiai Kiadó, vol. 126(4), pages 3667-3672, April.

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    More about this item

    Keywords

    Skewed distribution; Mean value; Adjusted mean value; Hirsch-index; Bibliometrics; Ranking of research units;
    All these keywords.

    JEL classification:

    • C46 - Mathematical and Quantitative Methods - - Econometric and Statistical Methods: Special Topics - - - Specific Distributions

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