Return of ChebNet: Understanding and Improving an Overlooked GNN on Long Range Tasks
Ali Hariri, Álvaro Arroyo, Alessio Gravina, Moshe Eliasof, Carola-Bibiane Schönlieb, Davide Bacciu, Kamyar Azizzadenesheli, Xiaowen Dong, Pierre Vandergheynst
TL;DR
ChebNet is revisited to address long-range dependencies, revealing that $K$-order Chebyshev filters can be competitive but risk unstable dynamics as the receptive field grows. The authors formulate Stable-ChebNet by enforcing antisymmetric weights in an ODE framework and solving with forward-Euler discretization, yielding non-dissipative propagation with purely imaginary Jacobian spectra and avoiding eigendecompositions or rewiring. Theoretical guarantees accompany empirical validation across OGB, LRGB, and heterophilic benchmarks, where Stable-ChebNet attains near state-of-the-art performance while preserving Chebyshev filter structure. Overall, the work repositions spectral GNNs as scalable, principled tools for long-range graph modeling with robust stability properties.
Abstract
ChebNet, one of the earliest spectral GNNs, has largely been overshadowed by Message Passing Neural Networks (MPNNs), which gained popularity for their simplicity and effectiveness in capturing local graph structure. Despite their success, MPNNs are limited in their ability to capture long-range dependencies between nodes. This has led researchers to adapt MPNNs through rewiring or make use of Graph Transformers, which compromises the computational efficiency that characterized early spatial message-passing architectures, and typically disregards the graph structure. Almost a decade after its original introduction, we revisit ChebNet to shed light on its ability to model distant node interactions. We find that out-of-box, ChebNet already shows competitive advantages relative to classical MPNNs and GTs on long-range benchmarks, while maintaining good scalability properties for high-order polynomials. However, we uncover that this polynomial expansion leads ChebNet to an unstable regime during training. To address this limitation, we cast ChebNet as a stable and non-dissipative dynamical system, which we coin Stable-ChebNet. Our Stable-ChebNet model allows for stable information propagation, and has controllable dynamics which do not require the use of eigendecompositions, positional encodings, or graph rewiring. Across several benchmarks, Stable-ChebNet achieves near state-of-the-art performance.
