Robust inequality comparisons

Working Paper 2010-163


This paper is concerned with the problem of ranking Lorenz curves in situations where the Lorenz curves intersect and no unambiguous ranking can be attained without introducing weaker ranking criteria than first-degree Lorenz dominance. To deal with such situations Aaberge (2009) introduced two alternative sequences of nested dominance criteria for Lorenz curves which was proved to characterize two separate systems of nested subfamilies of inequality measures. This paper uses the obtained characterization results to arrange the members of two different generalized Gini families of inequality measures into subfamilies according to their relationship to Lorenz dominance of various degrees. Since the various criteria of higher degree Lorenz dominance provide convenient computational methods, these results can be used to identify the largest subfamily of the

Authors: Rolf Aaberge , Magne Mogstad.

Keywords: The Lorenz curve, Lorenz dominance, rank-dependent measures of inequality, the Gini coefficient, generalized Gini families of inequality measures.
JEL: D31, D63.