# A note on the VC dimension of 1-dimensional GNNs

arXiv: https://arxiv.org/abs/2410.07829 · HTML: https://mlsanity.com/paper/2410.07829/

## Key facts

- Cited by 1 papers in the map (data through 14 Oct 2026).
- Builds on 8 of its 12 references that are in the map.
- First posted on arXiv 10 Oct 2024.

## Builds on (most cited first, 8 of 8)

- [How Powerful are Graph Neural Networks?](https://mlsanity.com/paper/1810.00826/) (2018)
- [Weisfeiler and Leman Go Neural: Higher-order Graph Neural Networks](https://mlsanity.com/paper/1810.02244/) (2018)
- [The Logic of Graph Neural Networks](https://mlsanity.com/paper/2104.14624/) (2021)
- [Neural Injective Functions for Multisets, Measures and Graphs via a Finite Witness Theorem](https://mlsanity.com/paper/2306.06529/) (2023)
- [WL meet VC](https://mlsanity.com/paper/2301.11039/) (2023)
- [Exponentially Improving the Complexity of Simulating the Weisfeiler-Lehman Test with Graph Neural Networks](https://mlsanity.com/paper/2211.03232/) (2022)
- [On the power of graph neural networks and the role of the activation function](https://mlsanity.com/paper/2307.04661/) (2023)
- [On dimensionality of feature vectors in MPNNs](https://mlsanity.com/paper/2402.03966/) (2024)

## Built on by (most cited first, 1 of 1)

- [Understanding Generalization in Node and Link Prediction](https://mlsanity.com/paper/2507.00927/) (2025)

## Abstract (arXiv)

Graph Neural Networks (GNNs) have become an essential tool for analyzing graph-structured data, leveraging their ability to capture complex relational information. While the expressivity of GNNs, particularly their equivalence to the Weisfeiler-Leman (1-WL) isomorphism test, has been well-documented, understanding their generalization capabilities remains critical. This paper focuses on the generalization of GNNs by investigating their Vapnik-Chervonenkis (VC) dimension. We extend previous results to demonstrate that 1-dimensional GNNs with a single parameter have an infinite VC dimension for unbounded graphs. Furthermore, we show that this also holds for GNNs using analytic non-polynomial activation functions, including the 1-dimensional GNNs that were recently shown to be as expressive as the 1-WL test. These results suggest inherent limitations in the generalization ability of even the most simple GNNs, when viewed from the VC dimension perspective.
