The New Measures of Lorenz Curve Asymmetry: Formulation and Hypothesis Testing




Measure, Lorenz curve, Income inequality, Asymmetry, Hypothesis, Bootstrap


The existence of an asymmetric empirical Lorenz curve requires a measure of asymmetry that directly involves the geometry of the Lorenz curve as a component of its formulation. Therefore, establishing hypothesis testing for Lorenz curve asymmetry is necessary to conclude whether the Lorenz curve exhibits symmetry in actual data. Consequently, this study aims to construct a measure of Lorenz curve asymmetry that utilizes the area and perimeter elements of the inequality subzones as its components and establish a procedure for hypothesis testing the symmetry of the Lorenz curve. This study proposes two types of asymmetry measures, Ra and Rp, constructed based on the ratio of area and perimeter obtained from the inequality subzone. These measures effectively capture the asymmetric phenomenon of the Lorenz curve and provide an economic interpretation of the values Ra and Rp. The Lorenz curve symmetry hypothesis testing, based on Ra and Rp through a nonparametric bootstrap, yields reliable results when applied to actual data.


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How to Cite

Fajar, M., Setiawan, S., & Iriawan, N. (2023). The New Measures of Lorenz Curve Asymmetry: Formulation and Hypothesis Testing. Decision Making: Applications in Management and Engineering, 7(1), 99–130.