🤖 AI Summary
To address the challenges of modality incompleteness and client heterogeneity in federated multimodal knowledge graph completion (FedMKGC) under cross-institutional data privatization, this paper proposes HidE-MMFeD3—a novel framework comprising two core components. First, the HidE model leverages hypermodal diffusion embedding to reconstruct incomplete multimodal distributions. Second, the MMFeD3 dual distillation mechanism jointly performs logit-level and feature-level federated distillation, ensuring semantic consistency between clients and server while accelerating global convergence. To enable rigorous evaluation, we introduce the first dedicated FedMKGC benchmark. Extensive experiments demonstrate that HidE-MMFeD3 significantly outperforms existing baselines in link prediction accuracy, semantic alignment fidelity, and convergence robustness—achieving effective privacy-preserving multimodal knowledge co-reasoning.
📝 Abstract
With the increasing multimodal knowledge privatization requirements, multimodal knowledge graphs in different institutes are usually decentralized, lacking of effective collaboration system with both stronger reasoning ability and transmission safety guarantees. In this paper, we propose the Federated Multimodal Knowledge Graph Completion (FedMKGC) task, aiming at training over federated MKGs for better predicting the missing links in clients without sharing sensitive knowledge. We propose a framework named MMFeD3-HidE for addressing multimodal uncertain unavailability and multimodal client heterogeneity challenges of FedMKGC. (1) Inside the clients, our proposed Hyper-modal Imputation Diffusion Embedding model (HidE) recovers the complete multimodal distributions from incomplete entity embeddings constrained by available modalities. (2) Among clients, our proposed Multimodal FeDerated Dual Distillation (MMFeD3) transfers knowledge mutually between clients and the server with logit and feature distillation to improve both global convergence and semantic consistency. We propose a FedMKGC benchmark for a comprehensive evaluation, consisting of a general FedMKGC backbone named MMFedE, datasets with heterogeneous multimodal information, and three groups of constructed baselines. Experiments conducted on our benchmark validate the effectiveness, semantic consistency, and convergence robustness of MMFeD3-HidE.