# Assessments of model-form uncertainty using Gaussian stochastic weight averaging for fluid-flow regression

@article{Morimoto2021AssessmentsOM, title={Assessments of model-form uncertainty using Gaussian stochastic weight averaging for fluid-flow regression}, author={Masaki Morimoto and Kai Fukami and Romit Maulik and Ricardo Vinuesa and Koji Fukagata}, journal={ArXiv}, year={2021}, volume={abs/2109.08248} }

We use Gaussian stochastic weight averaging (SWAG) to assess the model-form uncertainty associated with neural-network-based function approximation relevant to fluid flows. SWAG approximates a posterior Gaussian distribution of each weight, given training data, and a constant learning rate. Having access to this distribution, it is able to create multiple models with various combinations of sampled weights, which can be used to obtain ensemble predictions. The average of such an ensemble can be…

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