High-Dimensional Varying Coefficient Models with Functional Random Effects

Michael Law; Ya'acov Ritov

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arXiv · 2110.06426

High-Dimensional Varying Coefficient Models with Functional Random Effects

Michael Law·Ya'acov Ritov

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Abstract

We consider a sparse high-dimensional varying coefficients model with random effects, a flexible linear model allowing covariates and coefficients to have a functional dependence with time. For each individual, we observe discretely sampled responses and covariates as a function of time as well as time invariant covariates. Under sampling times that are either fixed and common or random and independent amongst individuals, we propose a projection procedure for the empirical estimation of all varying coefficients. We extend this estimator to construct confidence bands for a fixed number of varying coefficients.

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Michael Law, Ya'acov Ritov. 2021-10-13. High-Dimensional Varying Coefficient Models with Functional Random Effects. https://arxiv.org/abs/2110.06426

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