Some comments on Eggheʹs derivation of the impact factor distribution

In a recent paper, Egghe [Egghe, L. (in press). Mathematical derivation of the impact factor distribution. Journal of Informetrics] presents a mathematical analysis of the rank-order distribution of journal impact factors. The analysis is based on the central limit theorem. We criticize the empirical relevance of Eggheʹs analysis. More specifically, we argue that Eggheʹs analysis relies on an unrealistic assumption and we show that the analysis is not in agreement with empirical data.