Depth Uncertainty Networks for Active Learning

Chelsea Murray; James U. Allingham; Javier Antorán; José Miguel Hernández-Lobato

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arXiv · 2112.06796

Depth Uncertainty Networks for Active Learning

Chelsea Murray·James U. Allingham·Javier Antorán·José Miguel Hernández-Lobato

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Abstract

In active learning, the size and complexity of the training dataset changes over time. Simple models that are well specified by the amount of data available at the start of active learning might suffer from bias as more points are actively sampled. Flexible models that might be well suited to the full dataset can suffer from overfitting towards the start of active learning. We tackle this problem using Depth Uncertainty Networks (DUNs), a BNN variant in which the depth of the network, and thus its complexity, is inferred. We find that DUNs outperform other BNN variants on several active learning tasks. Importantly, we show that on the tasks in which DUNs perform best they present notably less overfitting than baselines.

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Chelsea Murray, James U. Allingham, Javier Antorán, José Miguel Hernández-Lobato. 2021-12-13. Depth Uncertainty Networks for Active Learning. https://arxiv.org/abs/2112.06796

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