论文标题
球形泊松点过程强度函数函数建模和测量运输的估计
Spherical Poisson Point Process Intensity Function Modeling and Estimation with Measure Transport
论文作者
论文摘要
近年来,人们对与机器学习和人工智能通常在空间统计的方法相关的方法和技术的应用越来越兴趣。在这里,在庆祝该期刊空间统计的十周年纪念日时,我们将正常化的流动汇总在一起,通常用于机器学习中的密度函数估计以及球形点过程,这是该期刊读者群体特别感兴趣的主题,以提出一种新方法,以建模非均匀的Poisson流程在范围内功能。该框架的核心思想是构建和估计,这是一个灵活的指图图,该图将吸收率在球体上的潜在强度函数转换为更简单的,参考,强度函数也在球体上。可以使用自动分化和随机梯度下降有效地进行地图估计,并且可以通过非参数引导程序直接进行不确定性定量。我们在仿真研究中研究了所提出的方法的生存能力,并说明了其在概念验证研究中的使用,在该研究中,我们对北太平洋中旋风事件的强度进行了建模。我们的实验表明,归一化流是一种灵活而直接的方法来建模强度在球体上的功能,但是它们产生良好拟合的潜力取决于徒图在实践中很难建立的beiptive图。
Recent years have seen an increased interest in the application of methods and techniques commonly associated with machine learning and artificial intelligence to spatial statistics. Here, in a celebration of the ten-year anniversary of the journal Spatial Statistics, we bring together normalizing flows, commonly used for density function estimation in machine learning, and spherical point processes, a topic of particular interest to the journal's readership, to present a new approach for modeling non-homogeneous Poisson process intensity functions on the sphere. The central idea of this framework is to build, and estimate, a flexible bijective map that transforms the underlying intensity function of interest on the sphere into a simpler, reference, intensity function, also on the sphere. Map estimation can be done efficiently using automatic differentiation and stochastic gradient descent, and uncertainty quantification can be done straightforwardly via nonparametric bootstrap. We investigate the viability of the proposed method in a simulation study, and illustrate its use in a proof-of-concept study where we model the intensity of cyclone events in the North Pacific Ocean. Our experiments reveal that normalizing flows present a flexible and straightforward way to model intensity functions on spheres, but that their potential to yield a good fit depends on the architecture of the bijective map, which can be difficult to establish in practice.