A Gradient Guided Diffusion Framework for Chance Constrained Programming
Boyang Zhang, Zhiguo Wang, Ya-Feng Liu
TL;DR
The paper introduces GGDOpt, a gradient-guided diffusion framework for solving chance-constrained programming under unknown uncertainty distributions. It reformulates CCP as sampling from the product distribution Qβ(x|ρ) ∝ r(x|ρ) Bβ(x) and leverages diffusion-based score modeling with gradient guidance to sample asymptotically optimal solutions. The authors establish convergence guarantees and practical error bounds, and validate the approach on synthetic problems and robust waveform design, achieving higher-quality solutions with substantial computational savings. By integrating feasibility-aware data generation, classifier-free conditional score training, and first- and second-order gradient guidance, GGDOpt extends diffusion-based optimization to a broad class of CCPs without explicit distributional knowledge.
Abstract
Chance constrained programming (CCP) is a powerful framework for addressing optimization problems under uncertainty. In this paper, we introduce a novel Gradient-Guided Diffusion-based Optimization framework, termed GGDOpt, which tackles CCP through three key innovations. First, GGDOpt accommodates a broad class of CCP problems without requiring the knowledge of the exact distribution of uncertainty-relying solely on a set of samples. Second, to address the nonconvexity of the chance constraints, it reformulates the CCP as a sampling problem over the product of two distributions: an unknown data distribution supported on a nonconvex set and a Boltzmann distribution defined by the objective function, which fully leverages both first- and second-order gradient information. Third, GGDOpt has theoretical convergence guarantees and provides practical error bounds under mild assumptions. By progressively injecting noise during the forward diffusion process to convexify the nonconvex feasible region, GGDOpt enables guided reverse sampling to generate asymptotically optimal solutions. Experimental results on synthetic datasets and a waveform design task in wireless communications demonstrate that GGDOpt outperforms existing methods in both solution quality and stability with nearly 80% overhead reduction.
