Private Prediction via Shrinkage

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Détails bibliographiques
Auteur principal:	Yan, Chao
Format:	Preprint
Publié:	2026
Sujets:	Machine Learning
Accès en ligne:	Acceder al recurso
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author	Yan, Chao
author_facet	Yan, Chao
contents	We study differentially private prediction introduced by Dwork and Feldman (COLT 2018): an algorithm receives one labeled sample set $S$ and then answers a stream of unlabeled queries while the output transcript remains $(\varepsilon,δ)$-differentially private with respect to $S$. Standard composition yields a $\sqrt{T}$ dependence for $T$ queries. We show that this dependence can be reduced to polylogarithmic in $T$ in streaming settings. For an oblivious online adversary and any concept class $\mathcal{C}$, we give a private predictor that answers $T$ queries with $\|S\|= \tilde{O}(VC(\mathcal{C})^{3.5}\log^{3.5}T)$ labeled examples. For an adaptive online adversary and halfspaces over $\mathbb{R}^d$, we obtain $\|S\|=\tilde{O}\left(d^{5.5}\log T\right)$.
format	Preprint
id	arxiv_https___arxiv_org_abs_2602_05219
institution	arXiv
publishDate	2026
record_format	arxiv
spellingShingle	Private Prediction via Shrinkage Yan, Chao Machine Learning We study differentially private prediction introduced by Dwork and Feldman (COLT 2018): an algorithm receives one labeled sample set $S$ and then answers a stream of unlabeled queries while the output transcript remains $(\varepsilon,δ)$-differentially private with respect to $S$. Standard composition yields a $\sqrt{T}$ dependence for $T$ queries. We show that this dependence can be reduced to polylogarithmic in $T$ in streaming settings. For an oblivious online adversary and any concept class $\mathcal{C}$, we give a private predictor that answers $T$ queries with $\|S\|= \tilde{O}(VC(\mathcal{C})^{3.5}\log^{3.5}T)$ labeled examples. For an adaptive online adversary and halfspaces over $\mathbb{R}^d$, we obtain $\|S\|=\tilde{O}\left(d^{5.5}\log T\right)$.
title	Private Prediction via Shrinkage
topic	Machine Learning
url	https://arxiv.org/abs/2602.05219

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