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

Eugene Garfield Institute for Scientific Information, 3501 Market Street, Philadelphia, PA 19104, U.S .A Email: [email protected] ! It is well known that uninformed science administrators offen use ISl's journal impact factors without taking into account the inherent citation characteristics of individual scientific disciplines. A rank normalized impact factor (rnlF) 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 rnlF is designated as rnlF, and equals (K R,+ l)IK, where R, 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 rnlF is compared with normalized impact factors proposed by earlier authors. The efficacy of the rnlF is illustrated in the cases of seven highiycited scientists, one each from seven different fields.