Sequential operator learning under dependent data

Rafael Oliveira

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arXiv · 2608.24426

Sequential operator learning under dependent data

Rafael Oliveira

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Abstract

Learning operators from sequentially collected data arises in adaptive experimental design, Bayesian optimization, and dynamical-system modelling, where observations may be dependent, and future inputs or sensing operators may depend on preceding data. We derive time-uniform self-normalized concentration bounds for stochastic processes in Hilbert spaces with vector-valued noise. We use these bounds to obtain regression-error guarantees for linear operators, including targets outside the Hilbert estimation space, and for nonlinear parametric operators trained with strongly convex losses and regularizers. Our results allow possibly infinite-dimensional inputs and outputs without independence or mixing assumptions, providing a major step towards convergence guarantees for adaptive operator learning and learning from stochastic dynamical data.

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Rafael Oliveira. 2026-09-07. Sequential operator learning under dependent data. https://arxiv.org/abs/2608.24426

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