GNN-MoE: Context-Aware Patch Routing using GNNs for Parameter-Efficient Domain Generalization
Mahmoud Soliman, Omar Abdelaziz, Ahmed Radwan, Anand, Mohamed Shehata
TL;DR
GNN-MoE addresses the challenge of domain generalization for Vision Transformers by introducing a graph-based, context-aware routing mechanism that directs patches to multiple Kronecker adapter experts. The method combines a GNN router operating on inter-patch graphs with parameter-efficient Kronecker adapters, achieving high performance with few trainable parameters. Empirically, it delivers state-of-the-art or competitive results on five DG benchmarks, significantly outperforming full fine-tuning and standard PEFT baselines while maintaining parameter efficiency. This graph-based routing strategy enhances robustness to domain shifts and can be extended to larger ViT families.
Abstract
Domain generalization (DG) seeks robust Vision Transformer (ViT) performance on unseen domains. Efficiently adapting pretrained ViTs for DG is challenging; standard fine-tuning is costly and can impair generalization. We propose GNN-MoE, enhancing Parameter-Efficient Fine-Tuning (PEFT) for DG with a Mixture-of-Experts (MoE) framework using efficient Kronecker adapters. Instead of token-based routing, a novel Graph Neural Network (GNN) router (GCN, GAT, SAGE) operates on inter-patch graphs to dynamically assign patches to specialized experts. This context-aware GNN routing leverages inter-patch relationships for better adaptation to domain shifts. GNN-MoE achieves state-of-the-art or competitive DG benchmark performance with high parameter efficiency, highlighting the utility of graph-based contextual routing for robust, lightweight DG.
