Imperial College London

ProfessorMichaelBronstein

Faculty of EngineeringDepartment of Computing

Visiting Professor
 
 
 
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Contact

 

m.bronstein Website

 
 
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Location

 

569Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@inproceedings{Topping:2022,
author = {Topping, J and Di, Giovanni F and Chamberlain, BP and Dong, X and Bronstein, MM},
title = {UNDERSTANDING OVER-SQUASHING AND BOTTLENECKS ON GRAPHS VIA CURVATURE},
year = {2022}
}

RIS format (EndNote, RefMan)

TY  - CPAPER
AB - Most graph neural networks (GNNs) use the message passing paradigm, in which node features are propagated on the input graph. Recent works pointed to the distortion of information flowing from distant nodes as a factor limiting the efficiency of message passing for tasks relying on long-distance interactions. This phenomenon, referred to as 'over-squashing', has been heuristically attributed to graph bottlenecks where the number of k-hop neighbors grows rapidly with k. We provide a precise description of the over-squashing phenomenon in GNNs and analyze how it arises from bottlenecks in the graph. For this purpose, we introduce a new edge-based combinatorial curvature and prove that negatively curved edges are responsible for the over-squashing issue. We also propose and experimentally test a curvature-based graph rewiring method to alleviate the over-squashing.
AU - Topping,J
AU - Di,Giovanni F
AU - Chamberlain,BP
AU - Dong,X
AU - Bronstein,MM
PY - 2022///
TI - UNDERSTANDING OVER-SQUASHING AND BOTTLENECKS ON GRAPHS VIA CURVATURE
ER -