{"title":"DA-PFL: Dynamic Affinity Aggregation in Personalized Federated Learning Under Class Imbalance.","authors":"Xu Yang,Jiyuan Feng,Yongxin Tong,Lingzhi Wang,Songyue Guo,Binxing Fang,Qing Liao","doi":"10.1109/tnnls.2025.3598818","DOIUrl":"https://doi.org/10.1109/tnnls.2025.3598818","url":null,"abstract":"Personalized federated learning (PFL) has become a hot research topic that can learn a personalized learning model for each client. Existing PFL models prefer to aggregate similar clients with similar data distribution to improve the performance of learning models. However, similarity-based PFL methods may exacerbate the class imbalance problem. In this article, we propose a novel dynamic affinity-based PFL (DA-PFL) model to alleviate the class imbalanced problem during federated learning. Specifically, we build an affinity metric from a complementary perspective to guide which clients should be aggregated. We then design a dynamic aggregation strategy that adjusts client aggregation based on the affinity metric in each round, thereby reducing the risk of class imbalance. Extensive experiments demonstrate that the proposed DA-PFL model can significantly improve the accuracy of each client in four real-world datasets with state-of-the-art comparison methods.","PeriodicalId":13303,"journal":{"name":"IEEE transactions on neural networks and learning systems","volume":"303 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yanxu Su,Qingyang Sheng,Xiasheng Shi,Chaoxu Mu,Changyin Sun
{"title":"Nesterov Accelerated Gradient Tracking With Adam for Distributed Online Optimization.","authors":"Yanxu Su,Qingyang Sheng,Xiasheng Shi,Chaoxu Mu,Changyin Sun","doi":"10.1109/tnnls.2025.3604059","DOIUrl":"https://doi.org/10.1109/tnnls.2025.3604059","url":null,"abstract":"This article presents an accelerated distributed optimization algorithm for online optimization problems over large-scale networks. The proposed algorithm's iteration only relies on local computation and communication. To effectively adapt to dynamic changes and achieve a fast convergence rate while maintaining good convergence performance, we design a new algorithm called NGTAdam. This algorithm combines the Nesterov acceleration technique with an adaptive moment estimation method. The convergence of NGTAdam is evaluated by evaluating its dynamic regret through the use of linear system inequality. For online convex optimization problems, we provide an upper bound on the dynamic regret of NGTAdam, which depends on the initial conditions and the time-varying nature of the optimization problem. Moreover, we show that if the time-varying part of this upper bound is sublinear with time, the dynamic regret is also sublinear. Through a variety of numerical experiments, we demonstrate that NGTAdam outperforms state-of-the-art distributed online optimization algorithms.","PeriodicalId":13303,"journal":{"name":"IEEE transactions on neural networks and learning systems","volume":"32 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144960179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Teresa Salazar, João Gama, Helder Araújo, Pedro Henriques Abreu
{"title":"Unveiling Group-Specific Distributed Concept Drift: A Fairness Imperative in Federated Learning","authors":"Teresa Salazar, João Gama, Helder Araújo, Pedro Henriques Abreu","doi":"10.1109/tnnls.2025.3601834","DOIUrl":"https://doi.org/10.1109/tnnls.2025.3601834","url":null,"abstract":"","PeriodicalId":13303,"journal":{"name":"IEEE transactions on neural networks and learning systems","volume":"27 1","pages":""},"PeriodicalIF":10.4,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144928064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}