Bayesian Metric Learning for Uncertainty Quantification in Image Retrieval

Frederik Warburg; Marco Miani; Silas Brack; Soren Hauberg

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arXiv · 2302.01332

Bayesian Metric Learning for Uncertainty Quantification in Image Retrieval

Frederik Warburg·Marco Miani·Silas Brack·Soren Hauberg

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Abstract

We propose the first Bayesian encoder for metric learning. Rather than relying on neural amortization as done in prior works, we learn a distribution over the network weights with the Laplace Approximation. We actualize this by first proving that the contrastive loss is a valid log-posterior. We then propose three methods that ensure a positive definite Hessian. Lastly, we present a novel decomposition of the Generalized Gauss-Newton approximation. Empirically, we show that our Laplacian Metric Learner (LAM) estimates well-calibrated uncertainties, reliably detects out-of-distribution examples, and yields state-of-the-art predictive performance.

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Frederik Warburg, Marco Miani, Silas Brack, Soren Hauberg. 2023-02-02. Bayesian Metric Learning for Uncertainty Quantification in Image Retrieval. https://arxiv.org/abs/2302.01332

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