Environmental and Ecological Statistics ( IF 3.0 ) Pub Date : 2021-01-08 , DOI: 10.1007/s10651-020-00476-y Nader Najari , Mohammad Q. Vahidi Asl
The Neyman–Scott processes introduced so far assume a symmetric distribution for the positions of the offspring points and this makes them inappropriate for modelling the skewed and bimodal clustered patterns and is a hindrance in fitting them to data that exhibit skewness or bimodality. In this paper, we apply the bivariate alpha-skew-normal distribution to the locations of the offspring points and introduce a Neyman–Scott process that regulates skewness and bimodality shapes in clustered point patterns. For this process, we obtain closed forms of the pair correlation function and the third-order intensity reweighted product density function and by use of the composite likelihood method, we fit the model to data. To examine the goodness-of-fit of the presented model, we use a statistical test based on the combined global scaled MAD envelopes. The use of the introduced process to model a clustered point pattern is illustrated by application to the locations of a species of trees in a rainforest dataset.
中文翻译:
Neyman–Scott过程与alpha偏态正态簇
到目前为止引入的Neyman-Scott过程假设后代点的位置对称分布,这使其不适合建模偏斜和双峰聚类模式,并且阻碍了将它们拟合到具有偏斜或双峰性的数据中。在本文中,我们将双变量α-偏态正态分布应用于后代点的位置,并介绍了Neyman-Scott过程,该过程调节聚类点模式中的偏度和双峰形状。在此过程中,我们获得了对相关函数和三阶强度重加权产品密度函数的闭合形式,并使用复合似然法将模型拟合到数据中。为了检查所提出模型的拟合优度,我们使用了基于组合的全球规模化MAD包络的统计检验。