English
Related papers

Related papers: Identifiability of Graphs with Small Color Classes…

200 papers

Recently, many works studied the expressive power of graph neural networks (GNNs) by linking it to the $1$-dimensional Weisfeiler--Leman algorithm ($1\text{-}\mathsf{WL}$). Here, the $1\text{-}\mathsf{WL}$ is a well-studied heuristic for…

Machine Learning · Computer Science 2023-05-31 Christopher Morris , Floris Geerts , Jan Tönshoff , Martin Grohe

Our starting point is the observation that if graphs in a class C have low descriptive complexity in first order logic, then the isomorphism problem for C is solvable by a fast parallel algorithm (essentially, by a simple combinatorial…

Computational Complexity · Computer Science 2007-05-23 Martin Grohe , Oleg Verbitsky

The Weisfeiler--Lehman (WL) test is a fundamental iterative algorithm for checking isomorphism of graphs. It has also been observed that it underlies the design of several graph neural network architectures, whose capabilities and…

Machine Learning · Computer Science 2025-06-13 Valentino Delle Rose , Alexander Kozachinskiy , Cristóbal Rojas , Mircea Petrache , Pablo Barceló

We investigate the relationship between various isomorphism invariants for finite groups. Specifically, we use the Weisfeiler-Leman dimension (WL) to characterize, compare and quantify the effectiveness and complexity of invariants for…

Group Theory · Mathematics 2021-11-24 Jendrik Brachter , Pascal Schweitzer

Current GNN architectures use a vertex neighborhood aggregation scheme, which limits their discriminative power to that of the 1-dimensional Weisfeiler-Lehman (WL) graph isomorphism test. Here, we propose a novel graph convolution operator…

Machine Learning · Computer Science 2020-09-22 Clemens Damke , Vitalik Melnikov , Eyke Hüllermeier

The WL-dimension of a graph X is the smallest positive integer m such that the m-dimensional Weisfeiler-Leman algorithm correctly tests the isomorphism between X and any other graph. It is proved that the WL-dimension of any circulant graph…

Combinatorics · Mathematics 2022-07-01 Ilia Ponomarenko

We prove that the combinatorial Weisfeiler-Leman algorithm of dimension $(3k+4)$ is a complete isomorphism test for the class of all graphs of rank width at most $k$. Rank width is a graph invariant that, similarly to tree width, measures…

Data Structures and Algorithms · Computer Science 2023-05-30 Martin Grohe , Daniel Neuen

The isomorphism problem is a fundamental problem in network analysis, which involves capturing both low-order and high-order structural information. In terms of extracting low-order structural information, graph isomorphism algorithms…

Data Structures and Algorithms · Computer Science 2023-07-28 Yifan Feng , Jiashu Han , Shihui Ying , Yue Gao

Given a pair of graphs $\textbf{A}$ and $\textbf{B}$, the problems of deciding whether there exists either a homomorphism or an isomorphism from $\textbf{A}$ to $\textbf{B}$ have received a lot of attention. While graph homomorphism is…

Data Structures and Algorithms · Computer Science 2021-07-08 Silvia Butti , Victor Dalmau

It is well known that almost all graphs are canonizable by a simple combinatorial routine known as color refinement, also referred to as the 1-dimensional Weisfeiler-Leman algorithm. With high probability, this method assigns a unique label…

Computational Complexity · Computer Science 2025-08-19 Oleg Verbitsky , Maksim Zhukovskii

In recent years, we have seen several approaches to the graph isomorphism problem based on "generic" mathematical programming or algebraic (Gr\"obner basis) techniques. For most of these, lower bounds have been established. In fact, it has…

Computational Complexity · Computer Science 2016-07-18 Christoph Berkholz , Martin Grohe

Recently, the Weisfeiler-Lehman (WL) graph isomorphism test was used to measure the expressive power of graph neural networks (GNN). It was shown that the popular message passing GNN cannot distinguish between graphs that are…

Machine Learning · Computer Science 2020-06-11 Haggai Maron , Heli Ben-Hamu , Hadar Serviansky , Yaron Lipman

We investigate the power of graph isomorphism algorithms based on algebraic reasoning techniques like Gr\"obner basis computation. The idea of these algorithms is to encode two graphs into a system of equations that are satisfiable if and…

Computational Complexity · Computer Science 2015-02-23 Christoph Berkholz , Martin Grohe

In recent years, graph neural networks (GNNs) have emerged as a powerful neural architecture to learn vector representations of nodes and graphs in a supervised, end-to-end fashion. Up to now, GNNs have only been evaluated empirically --…

In this paper, we show that the $(3k+4)$-dimensional Weisfeiler--Leman algorithm can identify graphs of treewidth $k$ in $O(\log n)$ rounds. This improves the result of Grohe & Verbitsky (ICALP 2006), who previously established the…

Data Structures and Algorithms · Computer Science 2024-04-26 Michael Levet , Puck Rombach , Nicholas Sieger

Line graph transformation has been widely studied in graph theory, where each node in a line graph corresponds to an edge in the original graph. This has inspired a series of graph neural networks (GNNs) applied to transformed line graphs,…

Machine Learning · Computer Science 2025-03-21 Fan Yang , Xingyue Huang

We present a novel approach for graph classification based on tabularizing graph data via new variants of the Weisfeiler-Leman algorithm and then applying methods for tabular data. The variants are obtained by modifying the underlying…

Machine Learning · Computer Science 2026-05-25 Reijo Jaakkola , Tomi Janhunen , Antti Kuusisto , Magdalena Ortiz , Matias Selin , Mantas Šimkus

Properties of the `$k$-equivalent' graph families constructed in Cai, F\"{u}rer and Immerman, and Evdokimov and Ponomarenko are analysed relative the the recursive $k$-dim WL method. An extension to the recursive $k$-dim WL method is…

Combinatorics · Mathematics 2011-01-28 B. L. Douglas

Graph problems are fundamentally challenging for large language models (LLMs). While LLMs excel at processing unstructured text, graph tasks require reasoning over explicit structure, permutation invariance, and computationally complex…

Machine Learning · Computer Science 2026-04-23 Angelo Zangari , Peyman Baghershahi , Sourav Medya

In this paper, we show that computing canonical labelings of graphs of bounded rank-width is in $\textsf{TC}^{2}$. Our approach builds on the framework of K\"obler & Verbitsky (CSR 2008), who established the analogous result for graphs of…

Data Structures and Algorithms · Computer Science 2024-04-26 Michael Levet , Puck Rombach , Nicholas Sieger