Remaining problems with the <http://arxiv.org/abs/1010.2379> "New Crown Indicator" (MNCS) of the CWTS
available at http://arxiv.org/abs/1010.2379 In their article, entitled "Towards a new crown indicator: some theoretical considerations," Waltman et al. (2010; at arXiv:1003.2167 <http://arxiv.org/abs/1003.2167> ) show that the "old crown indicator" of CWTS in Leiden was mathematically inconsistent and that one should move to the normalization as applied in the "new crown indicator." Although we now agree about the statistical normalization, the "new crown indicator" inherits the scientometric problems of the "old" one in treating subject categories of journals as a standard for normalizing differences in citation behavior among fields of science. We propose fractional counting of the citations in the citing documents as an alternative normalization for differences in citation behavior among fields of science. We further note that the "mean" is not a proper statistics for measuring differences among skewed distributions. Without changing the acronym of "MNCS," one could define the "Median Normalized Citation Score." The median is by definition equal to the 50th percentile. The indicator can thus easily be extended with the 1% (= 99th percentile) most highly-cited papers. The seeming disadvantage of having to use non-parametric statistics is more than compensated by possible gains in the precision. Authors: Loet Leydesdorff <http://arxiv.org/find/cs/1/au:+Leydesdorff_L/0/1/0/all/0/1> , Tobias Opthof <http://arxiv.org/find/cs/1/au:+Opthof_T/0/1/0/all/0/1> _____ How to evaluate universities in terms of their relative citation impacts: Fractional counting of citations and the normalization of differences among disciplines <http://arxiv.org/abs/1010.2465> available at http://arxiv.org/abs/1010.2465 Fractional counting of citations can improve on ranking of multi-disciplinary research units (such as universities) by normalizing the differences among fields of science in terms of differences in citation behavior. Furthermore, normalization in terms of citing papers abolishes the unsolved questions in scientometrics about the delineation of fields of science in terms of journals and normalization when comparing among different journals. Using publication and citation data of seven Korean research universities, we demonstrate the advantages and the differences in the rankings, explain the possible statistics, and suggest ways to visualize the differences in (citing) audiences in terms of a network. Authors: Loet Leydesdorff <http://arxiv.org/find/cs/1/au:+Leydesdorff_L/0/1/0/all/0/1> , Jung C. Shin <http://arxiv.org/find/cs/1/au:+Shin_J/0/1/0/all/0/1> ** apologies for cross-postings _____ Loet Leydesdorff Amsterdam School of Communications Research (ASCoR) Kloveniersburgwal 48, 1012 CX Amsterdam. Tel. +31-20-525 6598; fax: +31-842239111 <mailto:[email protected]> [email protected] ; <http://www.leydesdorff.net/> http://www.leydesdorff.net/ Visiting Professor 2007-2010, ISTIC, <http://www.istic.ac.cn/Eng/brief_en.html> Beijing; Honorary Fellow 2007-2010, SPRU, <http://www.sussex.ac.uk/spru/> University of Sussex Now available: <http://www.universal-publishers.com/book.php?method=ISBN&book=1581129378> The Knowledge-Based Economy: Modeled, Measured, Simulated, 385 pp.; US$ 18.95; <http://www.universal-publishers.com/book.php?method=ISBN&book=1581126956> The Self-Organization of the Knowledge-Based Society ; <http://www.universal-publishers.com/book.php?method=ISBN&book=1581126816> The Challenge of Scientometrics
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