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arXiv · 2305.17825

Multinomial Logistic Regression: Asymptotic Normality on Null Covariates in High-Dimensions

Kai Tan·Pierre C. Bellec
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Abstract

This paper investigates the asymptotic distribution of the maximum-likelihood estimate (MLE) in multinomial logistic models in the high-dimensional regime where dimension and sample size are of the same order. While classical large-sample theory provides asymptotic normality of the MLE under certain conditions, such classical results are expected to fail in high-dimensions as documented for the binary logistic case in the seminal work of Sur and Cand\`es [2019]. We address this issue in classification problems with 3 or more classes, by developing asymptotic normality and asymptotic chi-square results for the multinomial logistic MLE (also known as cross-entropy minimizer) on null covariates. Our theory leads to a new methodology to test the significance of a given feature. Extensive simulation studies on synthetic data corroborate these asymptotic results and confirm the validity of proposed p-values for testing the significance of a given feature.

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BibTeXRIS

Kai Tan, Pierre C. Bellec. 2023-05-28. Multinomial Logistic Regression: Asymptotic Normality on Null Covariates in High-Dimensions. https://arxiv.org/abs/2305.17825

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