Beyond Covariance Matrix: The Statistical Complexity of Private Linear Regression

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Chen, Fan, Li, Jiachun, Rakhlin, Alexander, Simchi-Levi, David
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866908630519906304
author Chen, Fan
Li, Jiachun
Rakhlin, Alexander
Simchi-Levi, David
author_facet Chen, Fan
Li, Jiachun
Rakhlin, Alexander
Simchi-Levi, David
contents We study the statistical complexity of private linear regression under an unknown, potentially ill-conditioned covariate distribution. Somewhat surprisingly, under privacy constraints the intrinsic complexity is \emph{not} captured by the usual covariance matrix but rather its $L_1$ analogues. Building on this insight, we establish minimax convergence rates for both the central and local privacy models and introduce an Information-Weighted Regression method that attains the optimal rates. As application, in private linear contextual bandits, we propose an efficient algorithm that achieves rate-optimal regret bounds of order $\sqrt{T}+\frac{1}α$ and $\sqrt{T}/α$ under joint and local $α$-privacy models, respectively. Notably, our results demonstrate that joint privacy comes at almost no additional cost, addressing the open problems posed by Azize and Basu (2024).
format Preprint
id arxiv_https___arxiv_org_abs_2502_13115
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Beyond Covariance Matrix: The Statistical Complexity of Private Linear Regression
Chen, Fan
Li, Jiachun
Rakhlin, Alexander
Simchi-Levi, David
Machine Learning
Artificial Intelligence
Cryptography and Security
Statistics Theory
We study the statistical complexity of private linear regression under an unknown, potentially ill-conditioned covariate distribution. Somewhat surprisingly, under privacy constraints the intrinsic complexity is \emph{not} captured by the usual covariance matrix but rather its $L_1$ analogues. Building on this insight, we establish minimax convergence rates for both the central and local privacy models and introduce an Information-Weighted Regression method that attains the optimal rates. As application, in private linear contextual bandits, we propose an efficient algorithm that achieves rate-optimal regret bounds of order $\sqrt{T}+\frac{1}α$ and $\sqrt{T}/α$ under joint and local $α$-privacy models, respectively. Notably, our results demonstrate that joint privacy comes at almost no additional cost, addressing the open problems posed by Azize and Basu (2024).
title Beyond Covariance Matrix: The Statistical Complexity of Private Linear Regression
topic Machine Learning
Artificial Intelligence
Cryptography and Security
Statistics Theory
url https://arxiv.org/abs/2502.13115