Predict+Optimize is a recently proposed framework which combines machine learning and constrained optimization, tackling optimization problems that contain parameters that are unknown at solving time. The goal is to predict the unknown parameters and use the estimates to solve for an estimated optimal solution to the optimization problem. However, all prior works have focused on the case where unknown parameters appear only in the optimization objective and not the constraints, for the simple reason that if the constraints were not known exactly, the estimated optimal solution might not even be feasible under the true parameters. The contributions of this paper are two-fold. First, we propose a novel and practically relevant framework for the Predict+Optimize setting, but with unknown parameters in both the objective and the constraints. We introduce the notion of a correction function, and an additional penalty term in the loss function, modelling practical scenarios where an estimated optimal solution can be modified into a feasible solution after the true parameters are revealed, but at an additional cost. Second, we propose a corresponding algorithmic approach for our framework, which handles all packing and covering linear programs. Our approach is inspired by the prior work of Mandi and Guns, though with crucial modifications and re-derivations for our very different setting. Experimentation demonstrates the superior empirical performance of our method over classical approaches.
翻译:预测+优化是最近提出的一个框架,它将机器学习和限制优化结合起来,处理包含在解决时未知参数的优化问题;目标是预测未知参数,利用估计数解决优化问题的最佳估计解决办法;然而,所有先前的工作都侧重于一个情况,即未知参数只出现在优化目标中,而不是限制,原因很简单,即如果不确切了解这些限制因素,估计的最佳解决办法在真实参数下可能甚至不可行。本文的贡献是双重的。首先,我们为预测+优化设置提出了一个新颖和实际相关的框架,但在目标和制约因素中都有未知参数。我们引入了纠正功能的概念,并在损失功能中增加了一个惩罚期,模拟实际假设,在揭示了真实参数后,估计的最佳解决办法可以修改为可行的解决办法,但成本增加。第二,我们提出了我们框架的相应算法方法,处理所有包装和涵盖线性程序。我们的方法受到Mandi和Guns先前的工作的启发,但有关键的修改和重新实验方法,以展示我们不同的实验方法。