Sparse polynomial chaos expansions (PCE) are an efficient and widely used surrogate modeling method in uncertainty quantification for engineering problems with computationally expensive models. To make use of the available information in the most efficient way, several approaches for so-called basis-adaptive sparse PCE have been proposed to determine the set of polynomial regressors ("basis") for PCE adaptively. We describe three state-of-the-art basis-adaptive approaches from the recent sparse PCE literature and extensively benchmark them in terms of global approximation accuracy on a large set of computational models representative of a wide range of engineering problems. Investigating the synergies between sparse regression solvers and basis adaptivity schemes, we find that virtually all basis-adaptive schemes outperform a static choice of basis. Three sparse solvers, namely Bayesian compressive sensing and two variants of subspace pursuit, perform especially well. Aggregating our results by model dimensionality and experimental design size, we identify combinations of methods that are most promising for the specific problem class. Additionally, we introduce a novel solver and basis adaptivity selection scheme guided by cross-validation error. We demonstrate that this meta-selection procedure provides close-to-optimal results in terms of accuracy, and significantly more robust solutions, while being more general than the case-by-case recommendations obtained by the benchmark.
翻译:为了以最有效的方式利用现有信息,我们建议了几种所谓的基础适应性稀薄的 PCE 方法,以确定适合 PCE 适应性的多角度递减器(“基数”)的组合。我们从最近稀少的 PCE 文献中描述了三种最先进的基础调整方法,并用代表一系列广泛的工程问题的大系列计算模型的全球近似精确度作为基准。我们采用了一种新颖的回归解析器和基础适应性计划之间的协同作用,我们发现几乎所有的基础适应性计划都超越了一个静态的基础选择。三种稀疏的解决方案,即Bayesian 压缩感测仪和子空间追求的两种变体,效果特别好。我们用模型的维度和实验性设计规模将我们的结果汇总起来,我们用最有希望的特定问题类方法的组合来确定。此外,我们采用了一种新型的递增回归处理器和基础适应性调整结果方案,我们通过一个更稳健的矩阵选择方法,我们通过一个更稳健的矩阵选择方法,我们通过一个更稳健的矩阵选择方法,通过一个更稳健的跨级的矩阵选择方法,我们通过一个更稳健的矩阵选择了更稳健的矩阵选择方案。