Highly Adaptive Ridge

Alejandro Schuler; Alexander Hagemeister; Mark van der Laan

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arXiv · 2410.02680

Highly Adaptive Ridge

Alejandro Schuler·Alexander Hagemeister·Mark van der Laan

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Abstract

In this paper we propose the Highly Adaptive Ridge (HAR): a regression method that achieves a $n^{-1/3}$ dimension-free L2 convergence rate in the class of right-continuous functions with square-integrable sectional derivatives. This is a large nonparametric function class that is particularly appropriate for tabular data. HAR is exactly kernel ridge regression with a specific data-adaptive kernel based on a saturated zero-order tensor-product spline basis expansion. We use simulation and real data to confirm our theory. We demonstrate empirical performance better than state-of-the-art algorithms for small datasets in particular.

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BibTeX RIS

Alejandro Schuler, Alexander Hagemeister, Mark van der Laan. 2024-10-03. Highly Adaptive Ridge. https://arxiv.org/abs/2410.02680

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