Characteristic function-based tests for spatial randomness

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Zeng, Yiran, Zimmerman, Dale L.
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866916959534186496
author Zeng, Yiran
Zimmerman, Dale L.
author_facet Zeng, Yiran
Zimmerman, Dale L.
contents We introduce a new type of test for complete spatial randomness that applies to mapped point patterns in a rectangle or a cube of any dimension. This is the first test of its kind to be based on characteristic functions and utilizes a weighted $L_2$-distance between the empirical and uniform characteristic functions. The test shows surprising connections to Ripley's $K$-function and Zimmerman's $\barω^2$ statistic. It is also simple to calculate and does not require adjusting for edge effects. An efficient algorithm is developed to find the asymptotic null distribution of the test statistic under the Cauchy weight function. This makes the test fast to compute. In simulations, our test shows varying sensitivity to different levels of spatial interaction depending on the scale parameter of the Cauchy weight function. Tests with different parameter values can be combined to create a Bonferroni-corrected omnibus test, which is more powerful than the popular $L$-test and the Clark-Evans test in most simulation settings of heterogeneity, aggregation and regularity, especially when the sample size is large. The simplicity of the empirical characteristic function makes it straightforward to extend our test to non-rectangular or sparsely sampled point patterns.
format Preprint
id arxiv_https___arxiv_org_abs_2504_07946
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Characteristic function-based tests for spatial randomness
Zeng, Yiran
Zimmerman, Dale L.
Methodology
Computation
We introduce a new type of test for complete spatial randomness that applies to mapped point patterns in a rectangle or a cube of any dimension. This is the first test of its kind to be based on characteristic functions and utilizes a weighted $L_2$-distance between the empirical and uniform characteristic functions. The test shows surprising connections to Ripley's $K$-function and Zimmerman's $\barω^2$ statistic. It is also simple to calculate and does not require adjusting for edge effects. An efficient algorithm is developed to find the asymptotic null distribution of the test statistic under the Cauchy weight function. This makes the test fast to compute. In simulations, our test shows varying sensitivity to different levels of spatial interaction depending on the scale parameter of the Cauchy weight function. Tests with different parameter values can be combined to create a Bonferroni-corrected omnibus test, which is more powerful than the popular $L$-test and the Clark-Evans test in most simulation settings of heterogeneity, aggregation and regularity, especially when the sample size is large. The simplicity of the empirical characteristic function makes it straightforward to extend our test to non-rectangular or sparsely sampled point patterns.
title Characteristic function-based tests for spatial randomness
topic Methodology
Computation
url https://arxiv.org/abs/2504.07946