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arXiv · 2207.13167

One Simple Trick to Fix Your Bayesian Neural Network

Piotr Tempczyk·Ksawery Smoczyński·Philip Smolenski-Jensen·Marek Cygan
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Abstract

One of the most popular estimation methods in Bayesian neural networks (BNN) is mean-field variational inference (MFVI). In this work, we show that neural networks with ReLU activation function induce posteriors, that are hard to fit with MFVI. We provide a theoretical justification for this phenomenon, study it empirically, and report the results of a series of experiments to investigate the effect of activation function on the calibration of BNNs. We find that using Leaky ReLU activations leads to more Gaussian-like weight posteriors and achieves a lower expected calibration error (ECE) than its ReLU-based counterpart.

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Piotr Tempczyk, Ksawery Smoczyński, Philip Smolenski-Jensen, Marek Cygan. 2022-07-26. One Simple Trick to Fix Your Bayesian Neural Network. https://arxiv.org/abs/2207.13167

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