arXiv:2511.18583stat.MLcs.LG2025-11

提出适用于依赖数据的差分隐私均值估计方法,突破传统独立假设限制。

Differential privacy with dependent data

  • 基于对数Sobolev不等式建模弱依赖,推广稳健均值估计器
  • 在有界与无界数据下实现渐近与有限样本隐私保证
  • 适用于用户级隐私、纵向回归等场景,适合隐私保护统计研究者

依赖数据广泛存在于社会科学与健康科学的统计研究中,常涉及敏感信息。差分隐私(DP)尤其是用户级DP为处理此类数据提供了自然的隐私形式化框架,但重复测量等引入的依赖性挑战了现有DP下的统计理论。在独立同分布( extit{iid})情形下,带噪的截尾均值估计器已被证明在标准(项级)和用户级DP下对均值$μ∈ eal^d$估计具有极小极大最优性。然而其在潜在依赖观测下的表现此前未被研究。本文填补这一空白,证明截尾均值估计器可在有界与无界数据下用于依赖数据,并在弱依赖条件下获得类似于 extit{iid}情形的渐近与有限样本保证。我们通过联合分布上的对数Sobolev不等式形式化依赖关系,将Karwa与Vadhan(2018)的稳定直方图方法推广至非 extit{iid}设置,进而估计截尾估计器的私密投影区间。所提出的项级均值估计器的保证可扩展至用户级均值估计,并通过随机响应直方图转移到局部模型。以这些均值估计器为基础,我们进一步拓展至随机效应模型、纵向线性回归与非参数回归。本工作是系统研究依赖数据差分隐私的初步尝试。

原文摘要 · Abstract (English)

Dependent data underlies many statistical studies in the social and health sciences, which often involve sensitive or private information. Differential privacy (DP) and in particular \textit{user-level} DP provide a natural formalization of privacy requirements for processing dependent data where each individual provides multiple observations to the dataset. However, dependence introduced, e.g., through repeated measurements challenges the existing statistical theory under DP-constraints. In \iid{} settings, noisy Winsorized mean estimators have been shown to be minimax optimal for standard (\textit{item-level}) and \textit{user-level} DP estimation of a mean $μ\in \R^d$. Yet, their behavior on potentially dependent observations has not previously been studied. We fill this gap and show that Winsorized mean estimators can also be used under dependence for bounded and unbounded data, and can lead to asymptotic and finite sample guarantees that resemble their \iid{} counterparts under a weak notion of dependence. For this, we formalize dependence via log-Sobolev inequalities on the joint distribution of observations. This enables us to adapt the stable histogram by Karwa and Vadhan (2018) to a non-\iid{} setting, which we then use to estimate the private projection intervals of the Winsorized estimator. The resulting guarantees for our item-level mean estimator extend to \textit{user-level} mean estimation and transfer to the local model via a randomized response histogram. Using the mean estimators as building blocks, we provide extensions to random effects models, longitudinal linear regression and nonparametric regression. Therefore, our work constitutes a first step towards a systematic study of DP for dependent data.

差分隐私依赖数据均值估计统计推断

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。