Simplified PCNet with Robustness
Abstract
Graph Neural Networks (GNNs) have garnered significant attention for their success in learning the representation of homophilic or heterophilic graphs. However, they cannot generalize well to real-world graphs with different levels of homophily. In response, the Possion-Charlier Network (PCNet), the previous work, allows graph representation to be learned from heterophily to homophily. Although PCNet alleviates the heterophily issue, there remain some challenges in further improving the efficacy and efficiency. In this paper, we simplify PCNet and enhance its robustness. We first extend the filter order to continuous values and reduce its parameters. Two variants with adaptive neighborhood sizes are implemented. Theoretical analysis shows our model's robustness to graph structure perturbations or adversarial attacks. We validate our approach through semi-supervised learning tasks on various datasets representing both homophilic and heterophilic graphs.
Benchmark Results
Tested on 4 datasets 8 baseline values reported too low
Tables show presented results in global context (best 3 papers + GCN + MLP).
Heterophilic Graphs
| # | Model | Accuracy ↑ | Paper |
|---|---|---|---|
| 1 | P^2GNN | 0.9672
±0.0147 | |
| 2 | DoG | 0.9660
±0.0210 | |
| 3 | GPF-plus | 0.9583
±0.0419 | |
| 11 | SPCNet-L | 0.9426
±0.0131 | This paper |
| 15 | SPCNet-D | 0.9393
±0.0128 | This paper |
| 17 | EvenNet | 0.9377
±0.0173 | This paper |
| 20 | OptBasisGNN | 0.9348
±0.0168 | This paper |
| 21 | JacobiConv | 0.9344
±0.0213 | This paper |
| 22 | BernNet | 0.9328
±0.0148 best reported | best at pub: A Quasi-Wasserstein Loss for Learning Graph Neural Networks (WWW 2023) Difference within reported uncertainty; not counted as underperformance. |
| 23 | ChebNetII | 0.9328
±0.0147 | This paper |
| 25 | PDE-GCN | 0.9324
±0.0203 | This paper |
| 28 | GPRGNN | 0.9295
±0.0131 best reported | best at pub: Node-oriented Spectral Filtering for Graph Neural Networks (2022) best today: GrokFormer: Graph Fourier Kolmogorov-Arnold Transformers (ICML 2024) Difference within reported uncertainty; not counted as underperformance. |
| 34 | MLP | 0.9230
±0.0070 best reported | |
| 46 | APPNP | 0.9131
±0.0197 best reported | best at pub: A Quasi-Wasserstein Loss for Learning Graph Neural Networks (WWW 2023) Difference within reported uncertainty; not counted as underperformance. |
| 47 | TWIRLS | 0.9131
±0.0336 | This paper |
| 53 | GraphSAGE | 0.9000
±0.0365 | |
| 70 | GCNII | 0.8918
±0.0443 best reported | best at pub: Convolutional Neural Networks on Graphs with Chebyshev Approximation, Revisited (NeurIPS 2022) best today: Piecewise Constant Spectral Graph Neural Network (TMLR 2025) Difference within reported uncertainty; not counted as underperformance. |
| 110 | ChebNet | 0.8628
±0.0262 | This paper |
| 170 | ARMA | 0.8397
±0.0377 | This paper |
| 220 | EGNN | 0.8134
±0.0156 | This paper |
| 257 | GCN | 0.7933
±0.0447 best reported | best at pub: Restructuring Graphs for Higher Homophily via Adaptive Spectral Clustering (AAAI 2022) best today: Graph Wave Networks (WWW 2025) Difference within reported uncertainty; not counted as underperformance. |
| # | Model | Accuracy ↑ | Paper |
|---|---|---|---|
| 1 | P^2GNN | 0.9541
±0.0272 | |
| 2 | ACM-GCN | 0.9480
±0.0380 | |
| 3 | RF-GCN | 0.9429 | |
| 4 | SPCNet-D | 0.9425
±0.0192 | This paper |
| 6 | SPCNet-L | 0.9362
±0.0213 | This paper |
| 9 | OptBasisGNN | 0.9299
±0.0185 | This paper |
| 10 | JacobiConv | 0.9295
±0.0246 | This paper |
| 16 | ChebNetII | 0.9230
±0.0148 | This paper |
| 17 | BernNet | 0.9213
±0.0164 | This paper |
| 18 | EvenNet | 0.9213
±0.0172 | This paper |
| 21 | APPNP | 0.9181
±0.0196 best reported | best at pub: LON-GNN: Spectral GNNs with Learnable Orthonormal Basis (2023) Difference within reported uncertainty; not counted as underperformance. |
| 22 | GPRGNN | 0.9157
±0.0196 | prev best: LON-GNN: Spectral GNNs with Learnable Orthonormal Basis (2023) Improvement within reported uncertainty; not highlighted. |
| 24 | MLP | 0.9136
±0.0070 best reported | best at pub: Node-oriented Spectral Filtering for Graph Neural Networks (2022) |
| 27 | TWIRLS | 0.8983
±0.0229 | This paper |
| 28 | PDE-GCN | 0.8973
±0.0135 | This paper |
| 35 | GCNII | 0.8918
±0.0396 best reported | best at pub: Convolutional Neural Networks on Graphs with Chebyshev Approximation, Revisited (NeurIPS 2022) best today: $P^2$GNN: Two Prototype Sets to boost GNN Performance (2026) Difference within reported uncertainty; not counted as underperformance. |
| 82 | ARMA | 0.8562
±0.0213 | This paper |
| 85 | ChebNet | 0.8533
±0.0104 best reported | best at pub: Node-oriented Spectral Filtering for Graph Neural Networks (2022) Difference within reported uncertainty; not counted as underperformance. |
| 117 | EGNN | 0.8380
±0.0460 best reported | best at pub: Dirichlet Energy Enhancement of Graph Neural Networks by Framelet Augmentation (2023) Difference within reported uncertainty; not counted as underperformance. |
| 138 | SAGE | 0.8269 | |
| 170 | GCN | 0.8082
±0.0360 best reported | best at pub: Restructuring Graphs for Higher Homophily via Adaptive Spectral Clustering (AAAI 2022) best today: Bayesian Neighborhood Adaptation for Graph Neural Networks (TMLR 2025) |
| # | Model | Accuracy ↑ | Paper |
|---|---|---|---|
| 1 | DiGGR | 0.4535
±0.0353 | |
| 2 | TRIGON | 0.4402
±0.0028 | |
| 3 | DoG | 0.4320
±0.0120 | |
| 11 | OptBasisGNN | 0.4239
±0.0052 | This paper |
| 21 | BernNet | 0.4179
±0.0101 best reported | best at pub: LON-GNN: Spectral GNNs with Learnable Orthonormal Basis (2023) best today: $P^2$GNN: Two Prototype Sets to boost GNN Performance (2026) Difference within reported uncertainty; not counted as underperformance. |
| 22 | ChebNetII | 0.4175
±0.0107 | This paper |
| 34 | JacobiConv | 0.4117
±0.0064 | This paper |
| 37 | SPCNet-D | 0.4089
±0.0061 | This paper |
| 38 | GCNII | 0.4082
±0.0179 best reported | best at pub: Feature Expansion for Graph Neural Networks (ICML 2023) best today: $P^2$GNN: Two Prototype Sets to boost GNN Performance (2026) |
| 40 | EvenNet | 0.4048
±0.0062 | This paper |
| 41 | APPNP | 0.4046
±0.0064 best reported | best at pub: A Quasi-Wasserstein Loss for Learning Graph Neural Networks (WWW 2023) Difference within reported uncertainty; not counted as underperformance. |
| 42 | MLP | 0.4026
±0.0108 best reported | best at pub: Heterophily-Aware Graph Attention Network (2023) Difference within reported uncertainty; not counted as underperformance. |
| 43 | SPCNet-L | 0.4023
±0.0070 | This paper |
| 52 | GPRGNN | 0.3992
±0.0067 best reported | best at pub: LON-GNN: Spectral GNNs with Learnable Orthonormal Basis (2023) best today: GrokFormer: Graph Fourier Kolmogorov-Arnold Transformers (ICML 2024) Difference within reported uncertainty; not counted as underperformance. |
| 55 | PDE-GCN | 0.3976
±0.0074 | This paper |
| 68 | GraphSAGE | 0.3899
±0.0085 | |
| 85 | TWIRLS | 0.3813
±0.0081 | This paper |
| 88 | ChebNet | 0.3802
±0.0023 best reported | best at pub: Node-oriented Spectral Filtering for Graph Neural Networks (2022) Difference within reported uncertainty; not counted as underperformance. |
| 111 | ARMA | 0.3767
±0.0054 | This paper |
| 135 | GCN | 0.3690 best reported | best at pub: Beyond Low-frequency Information in Graph Convolutional Networks (AAAI 2021) |
| 162 | MixHop | 0.3648
±0.0120 best reported | best at pub: Towards Deep Attention in Graph Neural Networks: Problems and Remedies (ICML 2023) |
| 182 | GAT | 0.3605
±0.0035 best reported | best at pub: Hierarchical Graph Transformer with Adaptive Node Sampling (NeurIPS 2022) |
| 224 | EGNN | 0.3516
±0.0064 | This paper |
LINKX Benchmarks
| # | Model | Accuracy ↑ | Paper |
|---|---|---|---|
| 1 | DC-GNN | 0.8669
±0.0022 | |
| 2 | M2M-GNN | 0.8594
±0.0040 | |
| 3 | GloGNN | 0.8574
±0.0042 | This paper |
| 10 | SPCNet-D | 0.8475
±0.0027 | This paper |
| 11 | LINKX | 0.8471
±0.0052 | This paper |
| 13 | GPRGNN | 0.8455
±0.0054 best reported | best at pub: Clarify Confused Nodes via Separated Learning (2023) |
| 17 | MixHop | 0.8363
±0.0054 best reported | best at pub: Uplifting Message Passing Neural Network with Graph Original Information (2022) Difference within reported uncertainty; not counted as underperformance. |
| 26 | ACM-GCN | 0.8298
±0.0063 best reported | best at pub: Clarify Confused Nodes via Separated Learning (2023) Difference within reported uncertainty; not counted as underperformance. |
| 27 | GCNII | 0.8292
±0.0059 | This paper |
| 28 | SPCNet-L | 0.8269
±0.0022 | This paper |
| 29 | GIN | 0.8268
±0.0032 | |
| 31 | GCN | 0.8247
±0.0027 | This paper |
| 36 | GAT | 0.8153
±0.0055 | This paper |
| 38 | H_2GCN | 0.8131
±0.0060 | This paper |
| 51 | MLP | 0.7534
±0.0064 best reported | best at pub: Clarify Confused Nodes via Separated Learning (2023) |
| 54 | WRGAT | 0.7432
±0.0053 | This paper |
