aiqbench analysis
This research advances Bayesian optimization by leveraging the separability between black-box and white-box variables in grey-box problems, utilizing a bilevel reformulation to satisfy constraints exactly without penalty functions or approximations. The method demonstrates robust performance across 13 benchmark tasks, achieving lower regret with reduced computational cost compared to standard approaches. This work represents a significant step forward in optimizing complex systems where partial physics-based models are available alongside expensive simulation components.
Exploiting Separability in Multi-Scale Grey-Box Bayesian Optimization
arXiv:2608.03045v1 Announce Type: new Abstract: We consider grey-box optimization problems where the decision variables naturally partition into black-box variables (as arguments to an expensive black-box function) and white-box variables, governed by a set of explicit, closed-form equations that also depend on the output of the black-box function. We exploit this separability through a bilevel reformulation: an outer Bayesian optimization (BO) to optimize the scalar objective as a function of black-box variables alone, while an inner problem solves the white-box subproblem via global optimization. The Gaussian process surrogate used in BO is therefore defined rather than and white-box constraints are satisfied exactly whenever the inner optimizer converges to a feasible point---without penalty functions, chance constraints, or moment approximations. On a suite of 13 benchmark problems, bilevel BO achieves lower regret, with fewer iterations and wall clock time. This advantage is robust to initialization set size, exploration parameters, and inner-solver choice.
Abstract:We consider grey-box optimization problems where the decision variables naturally partition into black-box variables (as arguments to an expensive black-box function) and white-box variables, governed by a set of explicit, closed-form equations that also depend on the output of the black-box function. We exploit this separability through a bilevel reformulation: an outer Bayesian optimization (BO) to optimize the scalar objective as a function of black-box variables alone, while an inner problem solves the white-box subproblem via global optimization. The Gaussian process surrogate used in BO is therefore defined rather than and white-box constraints are satisfied exactly whenever the inner optimizer converges to a feasible point---without penalty functions, chance constraints, or moment approximations. On a suite of 13 benchmark problems, bilevel BO achieves lower regret, with fewer iterations and wall clock time. This advantage is robust to initialization set size, exploration parameters, and inner-solver choice.
Machine Learning (cs.LG)
arXiv:2608.03045 [cs.LG]
(or arXiv:2608.03045v1 [cs.LG] for this version)
https://doi.org/10.48550/arXiv.2608.03045 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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