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Provable Guarantees For Robust Feature Selection in Sparse Linear Models in High-Dimensions
Proceedings of the 42nd Conference on Uncertainty in Artificial Intelligence, PMLR 337:4381-4426, 2026.
Abstract
We study feature selection (support recovery) in sparse linear models, including linear and logistic regression, under a strong adversarial contamination model where an adversary can arbitrarily corrupt a constant fraction of samples in the high-dimensional regime. Most of the existing methods target one or two aspects of this interesting problem: (1) achieving robustness against \emph{strong} adversaries, (2) handling adversarial corruption in \emph{both} features and labels, and (3) performing feature selection in \emph{high dimensions}. Our approach tackles all three issues simultaneously. We propose a trimmed maximum likelihood estimator with $\ell_1$-regularization, leading to a non-convex relaxation of an NP-hard combinatorial optimization problem. We prove that any locally optimal solution to this non-convex problem achieves \emph{near-minimax} optimal statistical rates, up to logarithmic factors. Critically, our method recovers the true support in a computationally efficient manner despite the intractability of the exact formulation. The resulting sample complexity scales only logarithmically with the ambient dimension, making it well-suited for high-dimensional settings. Furthermore, our framework accommodates heavy-tailed noise distributions under mild moment assumptions, requiring only that the fourth moment be bounded. We also validate our theoretical findings empirically.