Percentile Rank and Author Superiority Indexes for Evaluating Individual

In this paper we propose two new indexes to quantify the citation status of papers and authors. The Percentile Rank Index (PRI) indicates the citation rank of the author’s individual papers among the papers published in the same year and source (journal or multi-authored monograph or book.) PRI is independent of the paper’s age, specialty, or source journal size. The Author’s Superiority Index (ASI) is determined by the number of the author’s papers with a PRI at or above a specified value (99, 95, or 75). ASI allows comparisons across specialties and different time periods. The data necessary to calculate both the PRI and ASI can be obtained from Thomson-Reuters database Web of Science (www.isiknowledge.com) or other comparable databases. ------------------------------------------------The quantitative assessment of individual scientist’s contributions is still a hot question. The now classic paper by Jorge Hirsch (2005) which proposed his h-index has already been cited in over 250 papers as of March 2009, and this number continues to grow. The advantages and drawbacks of the h-index are widely discussed. Many modifications of the h-index have been suggested. For a recent review see Bornmann & Daniel (2009). To illustrate the problems with the h-index we provide citation data for two population geneticists (Table 1). They both have identical h-indexes (equal to 8), but quite different total citation numbers (87 and 391). From these data it is evident, that the h-index is not definitive or discriminating enough. Though Hirsch (2007) showed that the h-index is informative for predicting the future performance of scientists, the correlation of the values of h-index for two consecutive time periods for the same author is not strong. When examining a large group of scientists the h-index performs relatively well, but for individual authors it is not sufficiently predictive. However, it is probably impossible to characterize the impact of a scientist’s contribution to science with a single number. Indeed, Hirsch states this explicitly in a personal communication (2008) with one of the authors. All the citation indexes used for evaluatory purposes (there are many of them) are derivatives of the “raw” citation number. The latter is the number of papers, which cite the paper under consideration. Dealing with citation numbers we must remember that citedness of a paper