Stochastic Ordering under Weaker Likelihood-Ratio Shape Conditions

Z. Derbazi

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arXiv · 2605.11973

Stochastic Ordering under Weaker Likelihood-Ratio Shape Conditions

Z. Derbazi

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Abstract

We show that the shape hypothesis on a likelihood ratio can be weakened while retaining endpoint criteria for the hazard-rate and usual stochastic orders. The endpoint reduction persists under unimodality of the likelihood ratio and under a sign-pattern condition on the likelihood ratio minus one, with at most two sign changes and a negative right tail. It also follows from a direct superlevel-set criterion involving the same expression, which is useful in particular for discontinuous likelihood ratios.

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Z. Derbazi. 2026-05-12. Stochastic Ordering under Weaker Likelihood-Ratio Shape Conditions. https://arxiv.org/abs/2605.11973

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