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Series:   Elements in Econophysics

The κ-Statistics Approach to Income Distribution Analysis

Published online by Cambridge University Press:  11 April 2025

Fabio Clementi ,
Mauro Gallegati ,
Lisa Gianmoena ,
Giorgio Kaniadakis  and
Simone Landini
Fabio Clementi
Affiliation:
University of Macerata, Italy
Mauro Gallegati
Affiliation:
Marche Polytechnic University, Italy
Lisa Gianmoena
Affiliation:
University of Pisa, Italy
Giorgio Kaniadakis
Affiliation:
Politecnico di Torino, Italy
Simone Landini
Affiliation:
IRES Piemonte – Socioeconomic Research Institute of Piedmont

Summary

This Element presents the κ-generalized distribution, a statistical model tailored for the analysis of income distribution. Developed over years of collaborative, multidisciplinary research, it clarifies the statistical properties of the model, assesses its empirical validity and compares its effectiveness with other parametric models. It also presents formulas for calculating inequality indices within the κ-generalized framework, including the widely used Gini coefficient and the relatively lesser-known Zanardi index of Lorenz curve asymmetry. Through empirical illustrations, the Element criticizes the conventional application of the Gini index, pointing out its inadequacy in capturing the full spectrum of inequality characteristics. Instead, it advocates the adoption of the Zanardi index, accentuating its ability to capture the inherent heterogeneity and asymmetry in income distributions.
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Keywords

income distributioninequalityGini coefficientZanardi indexκ-generalized distribution
Type
Element
Information
Series: Elements in Econophysics
Online ISBN: 9781009446341
Publisher: Cambridge University Press
Print publication: 08 May 2025

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