Minimax Simple Bayes Estimators of a Normal Variance

Yuzo Maruyama

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arXiv · 2603.00553

Minimax Simple Bayes Estimators of a Normal Variance

Yuzo Maruyama

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Abstract

This paper is a follow-up to Maruyama and Strawderman (2006, Journal of Statistical Planning and Inference), which identified a new class of generalized Bayes estimators with a particularly simple form for estimating a normal variance under entropy loss. Although their previous work established the Bayesianity of these estimators, it did not provide a closed-form result for their minimaxity. In this paper, we revisit the problem and establish a definitive closed-form minimaxity result for this class of simple Bayes estimators.

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Yuzo Maruyama. 2026-02-28. Minimax Simple Bayes Estimators of a Normal Variance. https://arxiv.org/abs/2603.00553

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