Percentile Ranks and the Integrated Impact Indicator (I3)
Abstract
We tested Rousseau's (in press) recent proposal to define percentile classes in the case of the Integrated Impact Indicator (I3) so that the largest number in a set always belongs to the highest (100th) percentile rank class. In the case a set of nine uncited papers and one with citation, however, the uncited papers would all be placed in the 90th percentile rank. A lowly-cited document set would thus be advantaged when compared with a highly-cited one. Notwithstanding our reservations, we extended the program for computing I3 in Web-of-Science data (at http://www.leydesdorff.net/software/i3) with this option; the quantiles without a correction are now the default. As Rousseau mentions, excellence indicators (e.g., the top-10%) can be considered as special cases of I3: only two percentile rank classes are distinguished for the evaluation. Both excellence and impact indicators can be tested statistically using the z-test for independent proportions.
Keywords
Cite
@article{arxiv.1112.6281,
title = {Percentile Ranks and the Integrated Impact Indicator (I3)},
author = {Loet Leydesdorff and Lutz Bornmann},
journal= {arXiv preprint arXiv:1112.6281},
year = {2011}
}
Comments
A shorter version appears as a Letter to the Editor of the Journal of the American Society for Information Science and Technology (in press)