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arXiv · 2510.09174

Robustness and Regularization in Hierarchical Re-Basin

Benedikt Franke·Florian Heinrich·Markus Lange·Arne Raulf
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Abstract

This paper takes a closer look at Git Re-Basin, an interesting new approach to merge trained models. We propose a hierarchical model merging scheme that significantly outperforms the standard MergeMany algorithm. With our new algorithm, we find that Re-Basin induces adversarial and perturbation robustness into the merged models, with the effect becoming stronger the more models participate in the hierarchical merging scheme. However, in our experiments Re-Basin induces a much bigger performance drop than reported by the original authors.

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Benedikt Franke, Florian Heinrich, Markus Lange, Arne Raulf. 2025-10-10. Robustness and Regularization in Hierarchical Re-Basin. https://doi.org/10.14428/esann%2F2024.es2024-22

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