Rank-Normalized Impact Factor: A Way to Compare Journal Performance Across Subject Categories

摘要

It is well known that uninformed science administrators often use ISI's journal impact factors without taking into account the inherent citation characteristics of individual scientific disciplines. A rank normalized impact factor (rnIF) is proposed which involves use of order statistics for the complete set of journals within each JCR category. We believe the normalization procedure provides reliable and easily interpretable values. For any journal j, its rnIF is designated as rnIF_j and equals (K -R_j+ 1)/K, where R_j is the descending rank of journal j in its JCR category and K is the number of journals in the category. Note: JCR impact factor listings are published in descending order. The proposed rnIF is compared with normalized impact factors proposed by earlier authors. The efficacy of the rnIF is illustrated in the cases of seven highly-cited scientists, one each from seven different fields.