A Model-Based Derivative-Free Optimization Algorithm for Partially Separable Problems

Yichuan Liu; Yingzhou Li

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arXiv · 2506.21948

A Model-Based Derivative-Free Optimization Algorithm for Partially Separable Problems

Yichuan Liu·Yingzhou Li

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Abstract

We propose UPOQA, a derivative-free optimization algorithm for partially separable unconstrained problems, leveraging quadratic interpolation and a structured trust-region framework. By decomposing the objective into element functions, UPOQA constructs underdetermined element models and solves subproblems efficiently via a modified projected gradient method. Innovations include an approximate projection operator for structured trust regions, improved management of elemental radii and models, a starting point search mechanism, and support for hybrid black-white-box optimization, etc. Numerical experiments on 85 CUTEst problems demonstrate that \texttt{UPOQA} can significantly reduce the number of function evaluations. To quantify the impact of exploiting partial separability, we introduce the speed-up profile to further evaluate the acceleration effect. Results show that the speed-up of UPOQA over baselines is less significant in low-precision scenarios but becomes more pronounced in high-precision scenarios. Applications to quantum variational problems further validate its practical utility.

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BibTeX RIS

Yichuan Liu, Yingzhou Li. 2025-06-27. A Model-Based Derivative-Free Optimization Algorithm for Partially Separable Problems. https://arxiv.org/abs/2506.21948

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