Vincenzo Verardi2026-03-222026-03-22200410.1016/j.econlet.2004.05.001https://doi.org/10.1016/j.econlet.2004.05.001https://andeanlibrary.org/handle/123456789/83909enInequalityEconomic inequalityPanel dataIncome inequality metricsEconometricsSimple (philosophy)EconomicsProportionality (law)Income distributionLinear inequalityElectoral systems and income inequalitypreprint