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arXiv 2102.02731stat.MEstat.AP
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基于M-RA和混合先验的空间过程不均匀区域识别

Identifying regions of inhomogeneities in spatial processes via an M-RA and mixture priors

Marco H. Benedetti, Veronica J. Berrocal, Naveen N. Narisetty

摘要:

土壤被视为一种隐藏的资源,可以用来缓解和应对一些重大的全球环境挑战。具体来说,土壤中储存的有机碳,称为土壤有机碳(SOC),通过适当的土壤管理,可以帮助抵消燃料排放,提高粮食生产力,改善水质。尽管了解SOC的空间变异性对于有效的土壤管理至关重要,但由于收集SOC数据的成本高且耗时长,因此关于SOC的数据并不多。在这篇手稿中,我们提出了一个建模框架,可以用来获得一个更好的理解的依赖结构的空间过程中,通过识别区域内的空间域中的过程显示相同的空间相关范围。为了实现这一目标,我们提出了Katzfuss(2017)的多分辨率近似(M-RA)建模框架的泛化,最初是作为一种策略引入的,以减少分析大规模空间数据集时遇到的计算负担。为了允许空间过程的相关性可能以空间域的不同子区域中的不同范围为特征的可能性,我们提供了M-RA基函数权重,其中一个混合物组分具有收缩先验的两组分混合物。我们称这种方法为混合M-RA。将混合M-RA模型应用于平稳和非平稳数据表明,混合M-RA模型可以处理这两种类型的数据,可以正确地建立数据中的空间依赖结构的类型(例如,平稳与非平稳),并且可以识别局部平稳区域。

英文摘要:

Soils have been heralded as a hidden resource that can be leveraged to mitigate and address some of the major global environmental challenges. Specifically, the organic carbon stored in soils, called Soil Organic Carbon (SOC), can, through proper soil management, help offset fuel emissions, increase food productivity, and improve water quality. As collecting data on SOC is costly and time consuming, not much data on SOC is available, although understanding the spatial variability in SOC is of fundamental importance for effective soil management. In this manuscript, we propose a modeling framework that can be used to gain a better understanding of the dependence structure of a spatial process by identifying regions within a spatial domain where the process displays the same spatial correlation range. To achieve this goal, we propose a generalization of the Multi-Resolution Approximation (M-RA) modeling framework of Katzfuss (2017) originally introduced as a strategy to reduce the computational burden encountered when analyzing massive spatial datasets. To allow for the possibility that the correlation of a spatial process might be characterized by a different range in different subregions of a spatial domain, we provide the M-RA basis functions weights with a two-component mixture prior with one of the mixture components a shrinking prior. We call our approach the mixture M-RA. Application of the mixture M-RA model to both stationary and non-stationary data shows that the mixture M-RA model can handle both types of data, can correctly establish the type of spatial dependence structure in the data (e.g. stationary vs not), and can identify regions of local stationarity.

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。

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