New Letter to the Editor

Loet Leydesdorff loet at LEYDESDORFF.NET
Tue Mar 31 04:45:40 EDT 2015

PS. Of course, you should additionally normalize for PY and DT. 







Answering Christina: 

I would use fractionally counted, percentile normalized citation counts if you don’t wish to buy the results from “professional bibliometricians”. You will probably have to do the fractional counting by using (1/NRef) in the citing papers. (This is SNCS2 in the Leiden abbreviations system?) 


It is not the best way, but it is doable. You can perhaps use i3.exe at, but you would have to change the TC value by the fractionally counted ones in the input files. (I am not sure that everything works because I made this four years ago. Feel free to let me know if there are problems.) Use the Hazen (1914) option for percentile ranking.


The fractional counting enables you to prevent using WoS Subject Categories; percentiles are better than means because of the skew in the distributions. The results may be very different from using MNCS (which is “the standard practice”). Some evaluees may not like the results. I would use WoS and not Scopus because of the trade journals in the latter database. (The differences may be small, but it may matter for fractional counting.) 


I don’t share the expectation of concordance that some of our colleagues seem to entertain. The differences may be interesting. Since you would have all the data, you can show the differences, and also compare with the commercial set from Leiden (if you buy this data). The work is mainly collecting the data (TC) and the NRef values of the citing papers.







Bensman, S. J. (2007). Garfield and the impact factor. Annual Review of Information Science and Technology, 41(1), 93-155. 

Martyn, J., & Gilchrist, A. (1968). An Evaluation of British Scientific Journals. London: Aslib.

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