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arXiv · 2606.21636

Second order mixed moment inequalities based on Gram matrices

Sergio Scarlatti
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Abstract

Recently [LT; Theorem 3.1] showed an extension of Walker's inequality [W] based on $N=3$ random variables. In this note we prove that extension is just a particular three-dimensional instance of a general family of second order mixed moment inequalities based on Gram matrices of arbitrary random vectors. We also discuss some implications of these inequalities on Cramer-Rao lower bound for biased estimators.

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Sergio Scarlatti. 2026-06-19. Second order mixed moment inequalities based on Gram matrices. https://arxiv.org/abs/2606.21636

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