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arXiv · 2502.17391

The Empirical Impact of Reducing Symmetries on the Performance of Deep Ensembles and MoE

Abstract

Recent studies have shown that reducing symmetries in neural networks enhances linear mode connectivity between networks without requiring parameter space alignment, leading to improved performance in linearly interpolated neural networks. However, in practical applications, neural network interpolation is rarely used; instead, ensembles of networks are more common. In this paper, we empirically investigate the impact of reducing symmetries on the performance of deep ensembles and Mixture of Experts (MoE) across five datasets. Additionally, to explore deeper linear mode connectivity, we introduce the Mixture of Interpolated Experts (MoIE). Our results show that deep ensembles built on asymmetric neural networks achieve significantly better performance as ensemble size increases compared to their symmetric counterparts. In contrast, our experiments do not provide conclusive evidence on whether reducing symmetries affects both MoE and MoIE architectures.

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Andrei Chernov, Oleg Novitskij. 2025-02-24. The Empirical Impact of Reducing Symmetries on the Performance of Deep Ensembles and MoE. https://arxiv.org/abs/2502.17391

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