Addressing misspecification in contextual optimization

We study the predict-then-optimize framework approach, which combines machine learning and a downstream optimization task. This approach entails forecasting unknown parameters of an optimization problem and then resolving the optimization task based on these predictions. For example, consider an ene...

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Main Author: Bennouna, Omar
Other Authors: Ozdaglar, Asuman
Format: Thesis
Published: Massachusetts Institute of Technology 2024
Online Access:https://hdl.handle.net/1721.1/156138
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author Bennouna, Omar
author2 Ozdaglar, Asuman
author_facet Ozdaglar, Asuman
Bennouna, Omar
author_sort Bennouna, Omar
collection MIT
description We study the predict-then-optimize framework approach, which combines machine learning and a downstream optimization task. This approach entails forecasting unknown parameters of an optimization problem and then resolving the optimization task based on these predictions. For example, consider an energy allocation problem when the energy cost in different areas is uncertain. Despite the absence of precise energy cost values at the time of problem-solving, machine learning models are employed to predict these costs, and the resulting optimization problem, which consists for example of minimizing energy costs while meeting some minimal requirements, is solved using state-of-the-art optimization algorithms. When the chosen hypothesis set is well-specified (i.e. it contains the ground truth predictor), the SLO (Sequential Learning and Optimization) approach performs best among state of the art methods, and has provable performance guarantees. In the misspecified setting (i.e. the hypothesis set does not contain the ground truth predictor), the ILO (Integrated Learning and Optimization) approach seems to have better behavior in practice, but does not enjoy theoretical optimality guarantees. We focus on the misspecified setting. In this case, there is no known algorithm that rigorously solves this prediction problem. We provide a tractable ILO algorithm which successfully finds an optimal solution in this setting. Our approach consists of minimizing a surrogate loss which enjoys theoretical optimality guarantees as well as good behavior in practice. In particular, we show that our approach experimentally outperforms SLO and previous ILO methods in the misspecified setting.
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spelling mit-1721.1/1561382024-08-15T03:22:45Z Addressing misspecification in contextual optimization Bennouna, Omar Ozdaglar, Asuman Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science We study the predict-then-optimize framework approach, which combines machine learning and a downstream optimization task. This approach entails forecasting unknown parameters of an optimization problem and then resolving the optimization task based on these predictions. For example, consider an energy allocation problem when the energy cost in different areas is uncertain. Despite the absence of precise energy cost values at the time of problem-solving, machine learning models are employed to predict these costs, and the resulting optimization problem, which consists for example of minimizing energy costs while meeting some minimal requirements, is solved using state-of-the-art optimization algorithms. When the chosen hypothesis set is well-specified (i.e. it contains the ground truth predictor), the SLO (Sequential Learning and Optimization) approach performs best among state of the art methods, and has provable performance guarantees. In the misspecified setting (i.e. the hypothesis set does not contain the ground truth predictor), the ILO (Integrated Learning and Optimization) approach seems to have better behavior in practice, but does not enjoy theoretical optimality guarantees. We focus on the misspecified setting. In this case, there is no known algorithm that rigorously solves this prediction problem. We provide a tractable ILO algorithm which successfully finds an optimal solution in this setting. Our approach consists of minimizing a surrogate loss which enjoys theoretical optimality guarantees as well as good behavior in practice. In particular, we show that our approach experimentally outperforms SLO and previous ILO methods in the misspecified setting. S.M. 2024-08-14T20:10:13Z 2024-08-14T20:10:13Z 2024-05 2024-07-10T12:59:28.356Z Thesis https://hdl.handle.net/1721.1/156138 In Copyright - Educational Use Permitted Copyright retained by author(s) https://rightsstatements.org/page/InC-EDU/1.0/ application/pdf Massachusetts Institute of Technology
spellingShingle Bennouna, Omar
Addressing misspecification in contextual optimization
title Addressing misspecification in contextual optimization
title_full Addressing misspecification in contextual optimization
title_fullStr Addressing misspecification in contextual optimization
title_full_unstemmed Addressing misspecification in contextual optimization
title_short Addressing misspecification in contextual optimization
title_sort addressing misspecification in contextual optimization
url https://hdl.handle.net/1721.1/156138
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