This paper focuses on the estimation of horizontal inequity, remaining within the framework of the close equals groups approach started by Aronson, Johnson and Lambert (1994), and systematised by Urban and Lambert (2008). Within the framework of the close equals groups the choice of bandwidth,...

In this paper a method for analyzing the fairness of an income tax system when portioning the population into heterogeneous socio-economic groups is proposed. The equitable tax system is defined by the three axioms given by Kakwani and Lambert (1998) and, as they suggest, inequity is evaluated...

When calculating the Gini coefficient for distributions which include negative values, the Gini coefficient can be greater than one, which does not make evident its interpretation. In order to avoid this awkward result, common practice is either replacing the negative values with zeros, or...