arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2005.10285stat.ME
收藏

空间输出模型全局敏感性分析的泛函主成分分析

Functional principal component analysis for global sensitivity analysis of model with spatial output

T. V. E. Perrin, O. Roustant, J. Rohmer, O. Alata, J. P. Naulin, D. Idier, R. Pedreros, D. Moncoulon, P. Tinard

摘要:

出于沿海洪水风险评估,我们认为耗时的模拟器与空间输出。其目的是进行敏感性分析(SA),量化输入参数对输出的影响。有三个主要问题。首先,由于计算时间,标准SA技术不能直接应用于模拟器。第二,输出是无穷维的,或者如果输出是离散化的,至少是高维的。第三,空间输出是非平稳的,并表现出强烈的局部变化。我们表明,所有这些问题都可以通过使用功能PCA(FPCA)一起解决。我们首先指定一个功能的基础,如小波或B样条,旨在处理局部变化。其次,我们选择最有影响力的基础条款,无论是能量标准的基础正交归一化,或直接在原始基础上的惩罚回归方法。然后,FPCA进一步降低了维度,通过做PCA的最有影响力的基础系数,与ad-hoc度量。最后,快速评估元模型建立在少数选定的主成分。它们提供了一个可以进行SA的代理。作为一个副产品,我们得到的方差为基础的灵敏度指数的分析公式,推广已知的公式假设正交正规的基函数。

英文摘要:

Motivated by risk assessment of coastal flooding, we consider time-consuming simulators with a spatial output. The aim is to perform sensitivity analysis (SA), quantifying the influence of input parameters on the output. There are three main issues. First, due to computational time, standard SA techniques cannot be directly applied on the simulator. Second, the output is infinite dimensional, or at least high dimensional if the output is discretized. Third, the spatial output is non-stationary and exhibits strong local variations. We show that all these issues can be addressed all together by using functional PCA (FPCA). We first specify a functional basis, such as wavelets or B-splines, designed to handle local variations. Secondly, we select the most influential basis terms, either with an energy criterion after basis orthonormalization, or directly on the original basis with a penalized regression approach. Then FPCA further reduces dimension by doing PCA on the most influential basis coefficients, with an ad-hoc metric. Finally, fast-to-evaluate metamodels are built on the few selected principal components. They provide a proxy on which SA can be done. As a by-product, we obtain analytical formulas for variance-based sensitivity indices, generalizing known formula assuming orthonormality of basis functions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑