arXiv AI By Muhammad Uzair Shahid, Muhammad Zabil Mehboob

Does Federated Training Degrade Explainability? A Comparative Analysis of Grad-CAM Faithfulness in Centralized vs. Federated Deepfake Detection

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The paper investigates whether federated learning harms the faithfulness of Grad‑CAM explanations in deepfake detection. Using an EfficientNet‑B4 model on FaceForensics++ data distributed across five clients, the study finds that explanation quality is non‑monotonic: near‑IID and moderate heterogeneity yield explanations as good as or better than a centralized model, while extreme heterogeneity causes explanations to become spatially incoherent and causally misleading. The authors provide practical guidance for determining when federated deepfake detection can be safely deployed and when its explanations lose trustworthiness.

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arXiv Machine Learning
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By Ehsan Hallaji, Roozbeh Razavi-Far, Mehrdad Saif
arXiv AI
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Backdoors Leave Structural Traces: FedMAST for Backdoor Detection and Containment in Federated Learning

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By Srinivasan Subramanian, Kazi Aminul Islam, Md. Abdullah Al Hafiz Khan