这篇论文提出了一个新的隐私度量'可预测性'，比差分隐私更细致，还能和它一起用，很适合关注AI隐私的研究者。
该论文提出名为'可预测性'（predictability）的隐私度量框架，与差分隐私（DP）不同，它通过考虑攻击者的核心知识（部分泄露的数据）来评估隐私泄漏。研究证明可预测性与DP在一般情况下不可比较，但在最坏情形（仅一位个体未泄露且所有查询为二值）下，可预测性隐含互信息差分隐私。作者引入基于广义矩估计（GMM）的渐近分析方法，适用于由平稳遍历混合过程产生的泄露数据。最后，他们设计了一种基于可预测性校准的输出扰动方案，可与DP结合使用以提供细粒度隐私控制。
Predictability as a Fine-Grained Measure for Privacy
Differential privacy (DP) ensures rigorous individual-level privacy guarantees against even the most knowledgeable attackers, but its worst-case nature can impose a costly privacy-accuracy tradeoff. We introduce privacy via predictability, a fine-grained framework that explicitly incorporates the attacker's core knowledge, a compromised portion of the dataset generated by a stochastic process, and a specified family of queries. Predictability measures privacy leakage as the incremental gain in an attacker's ability to predict sensitive information about unknown individuals after observing the algorithm's output, beyond what can already be inferred from the compromised data. We show that predictability and DP are generally incomparable: each can be small while the other is large. However, in the worst-case regime where all but one individual is compromised, and all binary queries are considered sensitive, predictability implies mutual-information DP. More generally, predictability provides a finer-grained privacy metric tailored to specific sensitive information and specific attacker models. We introduce a general framework, using the generalized method of moments (GMM), to analyze asymptotic predictability when the compromised data is generated by a stationary, ergodic, mixing process. Using this analysis, we derive a predictability-calibrated output perturbation scheme for ERM. Our approach is complementary to DP and can be used alongside DP to provide fine-grained privacy control.