Dispersion measures for h-index: a study of the Brazilian researchers in the field of mathematics

Abstract

Although the h-index is considered a significant indicator to evaluate the researchers' performance, as it simultaneously measures aspects related to their scientific productivity and citation impact, several studies have pointed out its deficiencies and limitations. In this context, this study aims to evaluate the contribution of dci and dco indicators, two Hirsch-type indices, to measure the reasonableness of the h-index as a representation of the researcher’s scientific performance. The universe of analysis consisted of 116 Brazilian mathematicians holding CNPq grants. For each researcher, the number of articles, the number of citations per article and the year of publication were collected in the Scopus database. Then, for each researcher, the h-index and dci and dco indices were calculated. The dci and dco indicators allowed selective and productive researchers to be to distinguished more accurately. In addition, they contributed to estimate the possibility of the researcher to increase his/her h-index. The study concludes that the dci and dco indices were able to reliably measure the distribution dispersion of the researchers' citation impact together with their h-index. Consequently, they managed to estimate the representativeness of h-index as an indicator of the researchers' scientific performance in the field of mathematics in Brazil.