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20182026
most citedOn a bimodal Birnbaum-Saunders distribution with applications to lifetime data

9 citations · 24 across the 54 of their papers we have counts for

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Showing 2026 · stat.MEShow all

7 papers · 2 filters

stat.ME2026

Income inequality estimation with gamma mixtures

Roberto Vila, Helton Saulo, Felipe Quintino

This paper studies the estimation of the th Gini index under finite mixtures of gamma distributions. We derive closed-form expressions for the th Gini index and for the expec…

stat.ME2026

Unbiased estimation of normalized scale-invariant indices under the Gamma distribution

Roberto Vila, Helton Saulo, Felipe Quintino

We introduce a broad class of normalized scale-invariant indices (NSIIs) generated by measurable symmetric homogeneous functions and encompassing several well-known measures, inclu…

stat.ME2026

Length-biased Birnbaum-Saunders quantile regression with application to water evaporation

Helton Saulo, Tailine Nonato, Roberto Vila

Length-biased distributions arise naturally in environmental, reliability, and economic studies where the sampling mechanism favors larger observational units. In this paper, we pr…

stat.ME2026

The arithmetic-harmonic inequality index: Theory, inference, and finite-sample analysis

Roberto Vila, Helton Saulo

We investigate the arithmetic-harmonic inequality (AHI) index, a bounded and scale-invariant measure of dispersion for positive random variables, defined through the interplay betw…

stat.ME2026

Unifying the Hoover and Gini indices: Analytical, bias, and computational aspects

Roberto Vila, Helton Saulo, Felipe Quintino

We propose a new family of inequality indices that bridges the Hoover index and the Gini coefficient. The measure is defined as the normalized expected absolute value of a convex c…

stat.ME2026

Modeling double bounded data based on correlated gamma random variables

Roberto Vila, Felipe Quintino, Marcelo Bourguignon

Many types of bounded data defined on the unit interval arise naturally as ratios of the form . In the existing literature, the main statistical models proposed for this…

stat.ME2026

On the bias of the Hoover index estimator: Results for the gamma distribution

Roberto Vila, Helton Saulo

The Hoover index is a widely used measure of inequality with an intuitive interpretation, yet little is known about the finite-sample properties of its empirical estimator. In this…