arXiv:2409.04407cs.LG2024-09AAAI被引 1

攻击者通过设计缺失数据模式,操纵模型结果,甚至反转治疗效应方向。

Exploiting Missing Data Remediation Strategies using Adversarial Missingness Attacks

  • 构建双层优化框架,针对多种缺失数据处理方法设计对抗性缺失机制。
  • 在真实数据上仅用不足20%的缺失率,就将治疗效应从-1.61%扭曲至最高10%。
  • 适用于多种主流缺失处理方法,且对部分数据修改即可达成目标,隐蔽性强。

对抗性缺失(AM)攻击通过精心设计缺失数据模式来操纵模型训练结果,其核心特点是不插入恶意数据或扰动数据。现有方法仅适用于模型使用完整信息最大似然法处理缺失数据的情况。本文提出一种新框架,通过求解双层优化问题生成对抗性缺失机制,其中底层问题引入目标缺失修复技术的可微近似。作为实例,本文为三种常见方法——完整案例分析、均值填补和基于回归的填补——提供了适用于通用经验风险最小化(ERM)问题的AM攻击方案。实验表明,在真实数据上,即使缺失率低于20%,攻击仍有效。以真实世界双胞胎数据集为例,攻击可操控平均治疗效应(ATE),不仅改变其符号,还将真实值-1.61%扭曲至最高达10%。该结果在多种基于回归的估计器下均成立,即便攻击者仅能修改训练数据中的部分样本亦可实现。

原文摘要 · Abstract (English)

Adversarial Missingness (AM) attacks aim to manipulate model fitting by carefully engineering a missing data problem to achieve a specific malicious objective. AM attacks are significantly different from prior data poisoning attacks in that no malicious data inserted and no data is maliciously perturbed. Current AM attacks are feasible only under the assumption that the modeler (victim) uses full-information maximum likelihood methods to handle missingness. This work aims to remedy this limitation of AM attacks; in the approach taken here, the adversary achieves their goal by solving a bi-level optimization problem to engineer the adversarial missingness mechanism, where the lower level problem incorporates a differentiable approximation of the targeted missingness remediation technique. As instantiations of this framework, AM attacks are provided for three popular techniques: (i) complete case analysis, (ii) mean imputation, and (iii) regression-based imputation for general empirical risk minimization (ERM) problems. Experiments on real-world data show that AM attacks are successful with modest levels of missingness (less than 20%). Furthermore, we show on the real-world Twins dataset that AM attacks can manipulate the estimated average treatment effect (ATE) as an instance of the general ERM problems: the adversary succeeds in not only reversing the sign, but also in substantially inflating the ATE values from a true value of -1.61% to a manipulated one as high as 10%. These experimental results hold when the ATE is calculated using multiple regression-based estimators with different architectures, even when the adversary is restricted to modifying only a subset of the training data.

对抗攻击缺失数据因果推断双层优化

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。