# Learning Curves and Benign Overfitting of Spectral Algorithms in Large Dimensions

arXiv: https://arxiv.org/abs/2604.23212 · HTML: https://mlsanity.com/paper/2604.23212/

## Key facts

- No citing papers in the map yet (data through 14 Oct 2026).
- Builds on 17 of its 77 references that are in the map.
- First posted on arXiv 25 Apr 2026.

## Builds on (most cited first, 17 of 17)

- [Understanding deep learning requires rethinking generalization](https://mlsanity.com/paper/1611.03530/) (2016)
- [Deep Equals Shallow for ReLU Networks in Kernel Regimes](https://mlsanity.com/paper/2009.14397/) (2020)
- [Dimension free ridge regression](https://mlsanity.com/paper/2210.08571/) (2022)
- [Spectrum of inner-product kernel matrices in the polynomial regime and multiple descent phenomenon in kernel ridge regression](https://mlsanity.com/paper/2204.10425/) (2022)
- [A non-asymptotic theory of Kernel Ridge Regression: deterministic equivalents, test error, and GCV estimator](https://mlsanity.com/paper/2403.08938/) (2024)
- [Generalization in Kernel Regression Under Realistic Assumptions](https://mlsanity.com/paper/2312.15995/) (2023)
- [The Three Stages of Learning Dynamics in High-Dimensional Kernel Methods](https://mlsanity.com/paper/2111.07167/) (2021)
- [Sharp Asymptotics of Kernel Ridge Regression Beyond the Linear Regime](https://mlsanity.com/paper/2205.06798/) (2022)
- [Learning curves for Gaussian process regression with power-law priors and targets](https://mlsanity.com/paper/2110.12231/) (2021)
- [Optimal Rate of Kernel Regression in Large Dimensions](https://mlsanity.com/paper/2309.04268/) (2023)
- [Optimal Rates of Kernel Ridge Regression under Source Condition in Large Dimensions](https://mlsanity.com/paper/2401.01270/) (2024)
- [Generalization Error Curves for Analytic Spectral Algorithms under Power-law Decay](https://mlsanity.com/paper/2401.01599/) (2024)
- [Strong inductive biases provably prevent harmless interpolation](https://mlsanity.com/paper/2301.07605/) (2023)
- [A Comprehensive Analysis on the Learning Curve in Kernel Ridge Regression](https://mlsanity.com/paper/2410.17796/) (2024)
- [Learning Curves of Stochastic Gradient Descent in Kernel Regression](https://mlsanity.com/paper/2505.22048/) (2025)
- [Diagonal Over-parameterization in Reproducing Kernel Hilbert Spaces as an Adaptive Feature Model: Generalization and Adaptivity](https://mlsanity.com/paper/2501.08679/) (2025)
- [On the Pinsker bound of inner product kernel regression in large dimensions](https://mlsanity.com/paper/2409.00915/) (2024)

## Abstract (arXiv)

Existing large-dimensional theory for spectral algorithms resolves either the optimally tuned point or the interpolation limit, but leaves the under-regularized regime unexplored. We study the learning curve and benign overfitting of spectral algorithms in the large-dimensional setting where the sample size and dimension are of comparable order, i.e., n asymp dγ for some γ>0. We first consider inner-product kernels on the sphere mathbbSd-1 and establish a sharp asymptotic characterization of the excess risk across the full regularization path under various source conditions s ≥ 0, where s measures the relative smoothness of the regression function. Our results reveal that the learning curve is not simply U-shaped but instead consists of three distinct regimes: over-regularized, under-regularized, and interpolation regimes. This characterization allows us to fully capture the benign overfitting phenomenon, demonstrating that benign overfitting arises consistently across both the under-regularized and interpolation regimes whenever s is positive but no larger than a critical threshold. We further show that, in the sufficiently regularized regime, the kernel learning curve is recovered by an associated sequence model. Finally, we extend the learning-curve analysis to large-dimensional KRR for a class of kernels on general domains in ℝd whose low-degree eigenspaces satisfy spectral-scaling and hyper-contractivity conditions.
