Papers › Variational Bayesian Last Layers

Variational Bayesian Last Layers

17 Apr 2024arXiv:2404.11599archive 2025-07-28

James Harrison, John Willes, Jasper Snoek

We introduce a deterministic variational formulation for training Bayesian last layer neural networks. This yields a sampling-free, single-pass model and loss that effectively improves uncertainty estimation. Our variational Bayesian last layer (VBLL) can be trained and evaluated with only quadratic complexity in last layer width, and is thus (nearly) computationally free to add to standard architectures. We experimentally investigate VBLLs, and show that they improve predictive accuracy, calibration, and out of distribution detection over baselines across both regression and classification. Finally, we investigate combining VBLL layers with variational Bayesian feature learning, yielding a lower variance collapsed variational inference method for Bayesian neural networks.

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cholupdate vectorinstitute/vbll/vbll/layers/classification.py official repository ran · fixture could not drive it MIT (permissive) · 361e4fe66dd7affa · report
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tp vectorinstitute/vbll/vbll/layers/classification.py official repository ran · violated contract fingerprinted MIT (permissive) · 90e3b209489bfabc · report
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