lisa.perm: Permutation test

In spdyn: Exploratory Space-Time Data Analysis

Permutation test

Description

Computes a permutation test to assess the statistical significance of Local Indicators of Spatial Association –LISA.

Usage

lisa.perm(x,listw,perm=999,FUN=mean,DESV=sd,...)

Arguments

x	A numeric vector
listw	A listw object as produced by nb2listw or mat2listw. A list of spatial weights
perm	Number of permutations
FUN	By defautl FUN=mean. In general, a function to compute the central tendency of the data. It should return a scalar. See notes
DESV	Dispersion statistic. Defaults to sd
...	Further arguments passed to FUN

Details

This function implements a conditional permutation test to assess the statistical significance of the LISA. This is a distribution free test that overcomes the limitations of the standard assumption of normality.

Value

Returns a numeric matrix

Ii	Values of the Local Moran Statistics
p-val	Pseudo p-values
Zi	Standardized values of x

Note

There is no theoretical nor simulation work assessing the behavior of the Local Moran Staistic when the measure of central tendency is different from the mean.

Author(s)

Osmar Leandro Loaiza Quintero

References

Anselin, Luc (1992) Local Indicators of Spatial Association.

See Also

bilisa.perm, plot.lisaPerm

Examples

data(usinc, package='spdyn')

require(spdep)

lw<-nb2listw(
		poly2nb(usinc,queen=TRUE),style='W'
	)
	
mylisa <- lisa.perm(usinc$X2009,listw=lw)

plot(mylisa,usinc)

spdyn documentation built on Oct. 28, 2024, 3 p.m.