针对个性化联邦学习设计了分层遗忘框架,兼顾数据移除与模型个性化。
pFedUL: Layer-Aware Federated Unlearning for Personalized Federated Learning

- 按层区分共享与私有参数,量化客户影响并分层处理遗忘
- 在移除数据后仍保持剩余客户端97.3%的个性化准确率
- 适用于需合规删除数据且保留个性化能力的场景
联邦遗忘(FU)使模型能够移除特定数据贡献以符合如GDPR等法规要求。然而,现有方法多针对全局平均(FedAvg)框架,而实际中个性化联邦学习(pFL)如FedPer、FedRep、Ditto和FedBN因更优处理非独立同分布(non-IID)数据而广泛应用。这些方法将模型分为共享全局层与客户端专属个性化层,从根本上改变了遗忘的语义。本文首次形式化pFL下的联邦遗忘问题,揭示了共享层遗忘完整性和剩余客户端个性化保持之间的矛盾。提出pFedUL,一种分层感知的选择性遗忘框架,包含:(1)基于梯度的分层贡献归因,分别衡量目标客户端对共享与个性化参数的影响;(2)自适应选择性遗忘,对不同层类型采用差异化遗忘策略;(3)轻量级重校准协议,使剩余客户端以极小开销恢复个性化。引入个人化保持评分(PPS)和跨客户端公平性指数(CFI)评估新标准。在CIFAR-10、CIFAR-100和FEMNIST上,不同non-IID设置下的实验表明,pFedUL的遗忘效果接近全重训练,同时保持剩余客户端平均97.3%的个性化准确率,优于六种适配pFL的先进方法。
原文摘要 · Abstract (English)
Federated unlearning (FU) enables the removal of specific data contributions from federated learning (FL) models to comply with regulations such as the General Data Protection Regulation (GDPR). However, most existing FU methods are designed for the FedAvg paradigm, where all clients share a single global model. In practice, personalized federated learning (pFL) methods such as FedPer, FedRep, Ditto, and FedBN have become widely adopted due to their superior handling of non-IID data. These methods decompose the model into shared global layers and client-specific personalized layers, fundamentally altering the semantics of unlearning, yet this setting has received little attention. We formalize FU under the pFL paradigm, identifying a tension between unlearning completeness on shared layers and personalization preservation for remaining clients. We then propose pFedUL, a layer-aware selective unlearning framework comprising three components: (1) gradient-based layer-wise contribution attribution that separately quantifies the target client's influence on shared and personalized parameters, (2) adaptive selective unlearning that applies differentiated forgetting strategies across layer types, and (3) a lightweight recalibration protocol enabling remaining clients to restore personalization with minimal overhead. We further introduce two new metrics, Personalization Preservation Score (PPS) and Cross-client Fairness Index (CFI), to evaluate pFL-specific unlearning quality. Experiments on CIFAR-10, CIFAR-100, and FEMNIST under varying non-IID settings indicate that pFedUL achieves unlearning effectiveness comparable to full retraining while maintaining an average of 97.3\% personalized accuracy for remaining clients. Compared with six state-of-the-art FU methods adapted to the pFL setting, pFedUL consistently achieves superior personalization preservation.
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。