Matrix-Free Two-to-Infinity and One-to-Two Norms Estimation

Askar Tsyganov; Evgeny Frolov; Sergey Samsonov; Maxim Rakhuba

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arXiv · 2508.04444

Matrix-Free Two-to-Infinity and One-to-Two Norms Estimation

Askar Tsyganov·Evgeny Frolov·Sergey Samsonov·Maxim Rakhuba

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Abstract

In this paper, we propose new randomized algorithms for estimating the two-to-infinity and one-to-two norms in a matrix-free setting, using only matrix-vector multiplications. Our methods are based on appropriate modifications of Hutchinson's diagonal estimator and its Hutch++ version. We provide oracle complexity bounds for both modifications. We further illustrate the practical utility of our algorithms for Jacobian-based regularization in deep neural network training on image classification tasks. We also demonstrate that our methodology can be applied to mitigate the effect of adversarial attacks in the domain of recommender systems.

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BibTeX RIS

Askar Tsyganov, Evgeny Frolov, Sergey Samsonov, Maxim Rakhuba. 2026-01-17. Matrix-Free Two-to-Infinity and One-to-Two Norms Estimation. https://arxiv.org/abs/2508.04444

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