榜单推荐中的解耦学习与选择：噪声评分下的隐私与稳定性
Decoupled Learning and Selection in Slate Recommendation for Privacy and Stability Under Noisy Scores
- University of Bergen（卑尔根大学）
- Centre for the Science of Learning & Technology (SLATE)（学习与技术科学中心（SLATE））
- City University of Macau（澳门城市大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究提出榜单推荐中解耦评分学习与选择的方法，通过差分隐私范围契约和日志边际证书，在噪声评分下保证排序稳定性，实验验证了其有效性。
AI中文摘要：
我们将榜单推荐形式化为一个随机化评分学习器后接确定性选择的过程。首先，一个适当范围的差分隐私保证通过后处理在选择及其审计轨迹中得以保持。端到端的隐私仅在选择器输入是公开的或独立的、先前私有输出，或单独进行隐私核算时才成立；固定原始状态或候选信息则仅产生条件性保证。其次，我们推导出一个日志边际证书：有界评分引起的目标移动低于最小贪婪决策边际的一半时，保证排序榜单不变。受控的固定边际测试显示近线性指数缩放，经验斜率为$-0.220$（95%置信区间$[-0.231,-0.210]$），相对于独立噪声参考值$-1/4$。在OULAD、MovieLens-25M和Amazon Musical Instruments上的真实锚定实验表明，更大的锚定权重减少了评分噪声引起的排序变动。OULAD和EdNet证书检查验证了日志不等式的实现，而闭环模拟显示有界目标漂移和依赖设置的下游效用。因此，贡献在于一个隐私范围契约和一个可认证的评分到榜单稳定性机制，而非普遍的效用声明。
英文摘要：
We formalize slate recommendation as a randomized score learner followed by deterministic selection. First, an appropriately scoped differential-privacy guarantee passes through selection and its audit trace by post-processing. End-to-end privacy holds only when selector inputs are public or independent, previous private outputs, or separately privacy-accounted; fixing raw state or candidate information instead yields only a conditional guarantee. Second, we derive a logged margin certificate: bounded score-induced objective movement below half the smallest greedy decision margin guarantees that the ordered slate is unchanged. Controlled fixed-margin tests show near-linear exponent scaling, with an empirical slope of $-0.220$ (95% CI $[-0.231,-0.210]$) against the independent-noise reference $-1/4$. Real-anchor experiments on OULAD, MovieLens-25M, and Amazon Musical Instruments show that greater anchor weight reduces score-noise-induced ranking churn. OULAD and EdNet certificate checks validate the implementation of the logged inequality, while closed-loop simulations show bounded target drift and setting-dependent downstream utility. The contribution is therefore a privacy-scope contract and a certifiable score-to-slate stability mechanism, not a universal utility claim.
