collaborators

6 papers

cs.LG2026

A Unifying Relational Perspective on Expressive Lottery Tickets

Lorenz Kummer, Samir Moustafa, Anatol Ehrlich +4

Graph neural networks (GNNs) are widely used, but how parameter sparsity affects the expressivity of relational (RGNNs) and temporal (TGNNs) variants is poorly understood. The Stro…

cs.LG2026

XIMP: Cross Graph Inter-Message Passing for Molecular Property Prediction

Anatol Ehrlich, Lorenz Kummer, Vojtech Voracek +2

Accurate molecular property prediction is central to drug discovery, yet graph neural networks often underperform in data-scarce regimes and fail to surpass traditional fingerprint…

cs.LG2025

Visualization and Analysis of the Loss Landscape in Graph Neural Networks

Samir Moustafa, Lorenz Kummer, Simon Fetzel +2

Graph Neural Networks (GNNs) are powerful models for graph-structured data, with broad applications. However, the interplay between GNN parameter optimization, expressivity, and ge…

cs.LG2025

Weisfeiler and Leman Go Gambling: Why Expressive Lottery Tickets Win

Lorenz Kummer, Samir Moustafa, Anatol Ehrlich +4

The lottery ticket hypothesis (LTH) is well-studied for convolutional neural networks but has been validated only empirically for graph neural networks (GNNs), for which theoretica…

cs.LG2025

On the Relationship Between Robustness and Expressivity of Graph Neural Networks

Lorenz Kummer, Wilfried N. Gansterer, Nils M. Kriege

We investigate the vulnerability of Graph Neural Networks (GNNs) to bit-flip attacks (BFAs) by introducing an analytical framework to study the influence of architectural features,…

cs.LG2025

Crossfire: An Elastic Defense Framework for Graph Neural Networks Under Bit Flip Attacks

Lorenz Kummer, Samir Moustafa, Wilfried Gansterer +1

Bit Flip Attacks (BFAs) are a well-established class of adversarial attacks, originally developed for Convolutional Neural Networks within the computer vision domain. Most recently…