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arXiv · 2308.11511

Mode Combinability: Exploring Convex Combinations of Permutation Aligned Models

Adrián Csiszárik·Melinda F. Kiss·Péter Kőrösi-Szabó·Márton Muntag·Gergely Papp·Dániel Varga
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Abstract

We explore element-wise convex combinations of two permutation-aligned neural network parameter vectors $\Theta_A$ and $\Theta_B$ of size $d$. We conduct extensive experiments by examining various distributions of such model combinations parametrized by elements of the hypercube $[0,1]^{d}$ and its vicinity. Our findings reveal that broad regions of the hypercube form surfaces of low loss values, indicating that the notion of linear mode connectivity extends to a more general phenomenon which we call mode combinability. We also make several novel observations regarding linear mode connectivity and model re-basin. We demonstrate a transitivity property: two models re-based to a common third model are also linear mode connected, and a robustness property: even with significant perturbations of the neuron matchings the resulting combinations continue to form a working model. Moreover, we analyze the functional and weight similarity of model combinations and show that such combinations are non-vacuous in the sense that there are significant functional differences between the resulting models.

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Adrián Csiszárik, Melinda F. Kiss, Péter Kőrösi-Szabó, Márton Muntag, Gergely Papp, Dániel Varga. 2023-08-22. Mode Combinability: Exploring Convex Combinations of Permutation Aligned Models. https://arxiv.org/abs/2308.11511

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