Conformal Uncertainty Sets for Robust Optimization

Chancellor Johnstone; Bruce Cox

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arXiv · 2105.14957

Conformal Uncertainty Sets for Robust Optimization

Chancellor Johnstone·Bruce Cox

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Abstract

Decision-making under uncertainty is hugely important for any decisions sensitive to perturbations in observed data. One method of incorporating uncertainty into making optimal decisions is through robust optimization, which minimizes the worst-case scenario over some uncertainty set. We connect conformal prediction regions to robust optimization, providing finite sample valid and conservative ellipsoidal uncertainty sets, aptly named conformal uncertainty sets. In pursuit of this connection we explicitly define Mahalanobis distance as a potential conformity score in full conformal prediction. We also compare the coverage and optimization performance of conformal uncertainty sets, specifically generated with Mahalanobis distance, to traditional ellipsoidal uncertainty sets on a collection of simulated robust optimization examples.

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Chancellor Johnstone, Bruce Cox. 2021-05-31. Conformal Uncertainty Sets for Robust Optimization. https://arxiv.org/abs/2105.14957

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