Comparison and equality of generalized $\psi$-estimators

Matyas Barczy; Zsolt Páles

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arXiv · 2309.04773

Comparison and equality of generalized $\psi$-estimators

Matyas Barczy·Zsolt Páles

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Abstract

We solve the comparison problem for generalized $\psi$-estimators introduced in Barczy and P\'ales (2022). Namely, we derive several necessary and sufficient conditions under which a generalized $\psi$-estimator less than or equal to another $\psi$-estimator for any sample. We also solve the corresponding equality problem for generalized $\psi$-estimators. For applications, we solve the two problems in question for Bajraktarevi\'c-type- and quasi-arithmetic-type estimators. We also apply our results for some known statistical estimators such as for empirical expectiles and Mathieu-type estimators and for solutions of likelihood equations in case of normal, a Beta-type, Gamma, Lomax (Pareto type II), lognormal and Laplace distributions.

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Matyas Barczy, Zsolt Páles. 2023-09-09. Comparison and equality of generalized $\psi$-estimators. https://arxiv.org/abs/2309.04773

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