6 citations · 19 across the 10 of their papers we have counts for
5 papers · 2 filters
Remaining problems with the "New Crown Indicator" (MNCS) of the CWTS
Loet Leydesdorff, Tobias Opthof
In their article, entitled "Towards a new crown indicator: some theoretical considerations," Waltman et al. (2010; at arXiv:1003.2167) show that the "old crown indicator" of CWTS i…
Normalization at the field level: fractional counting of citations
Loet Leydesdorff, Tobias Opthof
Van Raan et al. (2010; arXiv:1003.2113) have proposed a new indicator (MNCS) for field normalization. Since field normalization is also used in the Leiden Rankings of universities,…
Scopus' SNIP Indicator
Loet Leydesdorff, Tobias Opthof
Rejoinder to Moed [arXiv:1005.4906]: Our main objection is against developing new indicators which, like some of the older ones (for example, the "crown indicator" of CWTS), do not…
Scopus's Source Normalized Impact per Paper (SNIP) versus a Journal Impact Factor based on Fractional Counting of Citations
Loet Leydesdorff, Tobias Opthof
Impact factors (and similar measures such as the Scimago Journal Rankings) suffer from two problems: (i) citation behavior varies among fields of science and therefore leads to sys…
Caveats for the journal and field normalizations in the CWTS ("Leiden") evaluations of research performance
Tobias Opthof, Loet Leydesdorff
The Center for Science and Technology Studies at Leiden University advocates the use of specific normalizations for assessing research performance with reference to a world average…