Optimal Excess Risk Bounds for Empirical Risk Minimization on $p$-Norm Linear Regression
- URL: http://arxiv.org/abs/2310.12437v2
- Date: Mon, 17 Jun 2024 22:48:42 GMT
- Title: Optimal Excess Risk Bounds for Empirical Risk Minimization on $p$-Norm Linear Regression
- Authors: Ayoub El Hanchi, Murat A. Erdogdu,
- Abstract summary: We show that, in the realizable case, under no moment assumptions, $O(d)$ samples are enough to exactly recover the target.
We extend this result to the case $p in (1, 2)$ under mild assumptions that guarantee the existence of the Hessian of the risk at its minimizer.
- Score: 19.31269916674961
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We study the performance of empirical risk minimization on the $p$-norm linear regression problem for $p \in (1, \infty)$. We show that, in the realizable case, under no moment assumptions, and up to a distribution-dependent constant, $O(d)$ samples are enough to exactly recover the target. Otherwise, for $p \in [2, \infty)$, and under weak moment assumptions on the target and the covariates, we prove a high probability excess risk bound on the empirical risk minimizer whose leading term matches, up to a constant that depends only on $p$, the asymptotically exact rate. We extend this result to the case $p \in (1, 2)$ under mild assumptions that guarantee the existence of the Hessian of the risk at its minimizer.
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