E-Index for measuring concentration

The goal of measuring the existing concentration of an economic magnitude among the elements in which it is distributed has been over the past years one of the major worries in the economic statistics arena. Among all the concentration indexes, the Gini index has been applied to a greater extent. This study considers that the traditional Gini index definition, according to a wide array of introductory statistics textbooks, is only applicable in the case of unitary frequency distributions. When dealing with nonunitary frequency distributions, it is possible to convert them into unitary ones, allowing for the application of the Gini index. Nevertheless, it can be appreciated how laborious such a task will be in those cases where the number of elements of the distribution is of considerable magnitude. The aim of this paper is to avoid this handicap by presenting an alternative index, the E-index.