Equivalent Gini coefficient, not shape parameter!

In a recent contribution in this journal, Gagolewski et al. (Scientometrics 127(5):2829–2845, 2022) study a new model—the so-called 3 dimensions of scientific impact (3DSI) model—for representing a rank size distribution. The model depends on three parameters/dimensions: the total number of papers, the total number of citations and a third parameter, ρ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho$$\end{document}, recognized by the authors as a shape parameter. We prove that ρ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho$$\end{document} is an equivalent Gini coefficient.