statistical significance and effect sizes Leiden Rankings

Appendix to:

Leydesdorff, L., Bornmann, L., & Mingers, J. (2017). Statistical Significance and Effect Sizes of Differences among Research Universities at the Level of Nations and Worldwide based on the Leiden Rankings; in preparation.

Appendix 1

The measurement of effect sizes and the statistical significance of differences among universities using the Leiden Rankings.

1. Download the program from http://www.leydesdorff.net/software/leiden/leiden.exe

2. Download the data at http://www.leidenranking.com/downloads in the Excel format.

3. Copy the fields “university,” country,” “field,” “period,” “fractional,” “p,” “p_top10,” “PP_top10_lb,” and “PP_top10_ub” for the selection that one wishes to analyze to a separate worksheet; save this worksheet as “CSV (comma delimited)” to a file leiden.csv in the same folder as the program. Do not use another format (for Apple or DOS), since only this format preserves the diacritical characters. (The file used for this study can be found here.)

4. Run the program; read the .net and .vec files into Pajek for the country under study. Within Pajek: > Options > Read – Write > UTF8;

5. Use Network > Create new network > Transform > Remove > Lines > higher than > 1.96 for generating a file at the 5% level; mutatis mutandis.

6. Draw > (Network + Vector) > Export > 2D > VOSviewer. The vector file is needed for the node sizes in Pajek. One can update layout and clustering in VOSviewer.