论文标题
通用时刻问题的统一框架:一种新颖的原始偶尔方法
A Unified Framework for Generalized Moment Problems: a Novel Primal-Dual Approach
论文作者
论文摘要
广义力矩问题优化具有广义力矩约束的一类分布的功能期望,即目前的功能可以是任何可测量的函数。这些问题最近引起了人们的兴趣,因为它们在表示非标准力矩约束方面的灵活性,例如几何均值约束,熵约束和指数型瞬间约束。尽管研究的兴趣越来越大,但这些问题的分析解决方案主要缺少,研究人员必须满足于次优的范围或数值方法,这些方法是次优的或仅适用于某些特殊情况。此外,针对特定问题结构量身定制了用于为标准力矩问题开发封闭形式解决方案的技术。在本文中,我们提出了一个框架,该框架在任何时刻的问题上都提供统一的治疗方法。该框架的关键要素是一种新型的原始偶尔最佳条件。这种最佳条件使我们能够将原始的无限维度问题减少到具有有限数量变量的非线性方程系统。在解决三个特定的力矩问题时,该框架展示了一个清晰的路径,以识别分析解决方案(如果有可用),否则,它会产生半分析解决方案,从而导致有效的数值算法。最后,通过数值实验,我们通过解决力矩问题和分配强大的新闻供应商问题来提供有关结果算法性能的进一步证据。
Generalized moment problems optimize functional expectation over a class of distributions with generalized moment constraints, i.e., the function in the moment can be any measurable function. These problems have recently attracted growing interest due to their great flexibility in representing nonstandard moment constraints, such as geometry-mean constraints, entropy constraints, and exponential-type moment constraints. Despite the increasing research interest, analytical solutions are mostly missing for these problems, and researchers have to settle for nontight bounds or numerical approaches that are either suboptimal or only applicable to some special cases. In addition, the techniques used to develop closed-form solutions to the standard moment problems are tailored for specific problem structures. In this paper, we propose a framework that provides a unified treatment for any moment problem. The key ingredient of the framework is a novel primal-dual optimality condition. This optimality condition enables us to reduce the original infinite dimensional problem to a nonlinear equation system with a finite number of variables. In solving three specific moment problems, the framework demonstrates a clear path for identifying the analytical solution if one is available, otherwise, it produces semi-analytical solutions that lead to efficient numerical algorithms. Finally, through numerical experiments, we provide further evidence regarding the performance of the resulting algorithms by solving a moment problem and a distributionally robust newsvendor problem.