arXiv Machine Learning By Jinrun Liu, Bai Yan, Tengfei Liu, Qunfeng Liu, Jian Yang, Shi Cheng, Yuhui Shi, Qi Zhao

Learning to Design Convex Relaxations for Nonconvex Optimization

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The paper introduces AutoConvexRelax, a learning-based framework that automates the design of convex relaxations for nonconvex optimization problems. By representing a problem as a tripartite graph of variables, symbolic terms, and objective/constraint positions, the method learns a policy to compose symbolic rewrites that generate valid relaxation trajectories. Experiments on quadratic and fractional problems show that the learned policy improves McCormick lower bounds by 13.52% and achieves near‑semidefinite bounds while using smaller formulations.

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