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arXiv · 2504.00480

Preconditioned Additive Gaussian Processes with Fourier Acceleration

Theresa Wagner·Tianshi Xu·Franziska Nestler·Yuanzhe Xi·Martin Stoll
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Abstract

Gaussian processes (GPs) are crucial in machine learning for quantifying uncertainty in predictions. However, their associated covariance matrices, defined by kernel functions, are typically dense and large-scale, posing significant computational challenges. This paper introduces a matrix-free method that utilizes the Non-equispaced Fast Fourier Transform (NFFT) to achieve nearly linear complexity in the multiplication of kernel matrices and their derivatives with vectors for a predetermined accuracy level. To address high-dimensional problems, we propose an additive kernel approach. Each sub-kernel in this approach captures lower-order feature interactions, allowing for the efficient application of the NFFT method and potentially increasing accuracy across various real-world datasets. Additionally, we implement a preconditioning strategy that accelerates hyperparameter tuning, further improving the efficiency and effectiveness of GPs.

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Theresa Wagner, Tianshi Xu, Franziska Nestler, Yuanzhe Xi, Martin Stoll. 2025-04-01. Preconditioned Additive Gaussian Processes with Fourier Acceleration. https://arxiv.org/abs/2504.00480

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