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arXiv · 1705.03604

Nonuniformity of P-values Can Occur Early in Diverging Dimensions

Yingying Fan·Emre Demirkaya·Jinchi Lv
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Abstract

Evaluating the joint significance of covariates is of fundamental importance in a wide range of applications. To this end, p-values are frequently employed and produced by algorithms that are powered by classical large-sample asymptotic theory. It is well known that the conventional p-values in Gaussian linear model are valid even when the dimensionality is a non-vanishing fraction of the sample size, but can break down when the design matrix becomes singular in higher dimensions or when the error distribution deviates from Gaussianity. A natural question is when the conventional p-values in generalized linear models become invalid in diverging dimensions. We establish that such a breakdown can occur early in nonlinear models. Our theoretical characterizations are confirmed by simulation studies.

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Yingying Fan, Emre Demirkaya, Jinchi Lv. 2017-05-10. Nonuniformity of P-values Can Occur Early in Diverging Dimensions. https://arxiv.org/abs/1705.03604

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