Finite population framework for a quantile-based inequality indicator

Several statistical indicators exist for the measurement of economic in equality. These are mostly based on distribution moments or depend on few per centiles at the tails of the distribution, selected a priori. This work analyzes a re cently proposed quantile-based income inequality indicator, which solely depends on quantiles and considers the whole distribution. It provides for this indicator a complete finite population estimation framework that works also for data collected with complex sampling design. Simulations based on Italian EU-SILC 2017 data demonstrates that the proposed direct estimator has large accuracy, precision and robustness to outlying observations.