Using Random Noise Equivariantly to Boost Graph Neural Networks Universally
Xiyuan Wang, Muhan Zhang
TL;DR
This work addresses the challenge of enhancing Graph Neural Networks (GNNs) expressivity without sacrificing generalization when using random noise as input features. It introduces Equivariant Noise GNN (ENGNN), a symmetry-aware architecture that processes noisy inputs in an invariant-equivariant fashion via a novel DeepSet-inspired aggregator, preserving permutation symmetries on both nodes and noise channels. The authors provide a theoretical framework linking noise-induced sample complexity to noise-space symmetry and prove that the proposed aggregator can universally approximate equivariant functions, while experiments show ENGNN improves performance across node, link, subgraph, and graph-level tasks with comparable scalability to standard MPNNs. Overall, ENGNN offers a general, task-agnostic method to boost GNN expressivity across diverse graph problems, with strong theoretical guarantees and broad empirical validation.
Abstract
Recent advances in Graph Neural Networks (GNNs) have explored the potential of random noise as an input feature to enhance expressivity across diverse tasks. However, naively incorporating noise can degrade performance, while architectures tailored to exploit noise for specific tasks excel yet lack broad applicability. This paper tackles these issues by laying down a theoretical framework that elucidates the increased sample complexity when introducing random noise into GNNs without careful design. We further propose Equivariant Noise GNN (ENGNN), a novel architecture that harnesses the symmetrical properties of noise to mitigate sample complexity and bolster generalization. Our experiments demonstrate that using noise equivariantly significantly enhances performance on node-level, link-level, subgraph, and graph-level tasks and achieves comparable performance to models designed for specific tasks, thereby offering a general method to boost expressivity across various graph tasks.
