local_g: Local G

In sfdep: Spatial Dependence for Simple Features

Local G

Description

Calculate the local Geary statistic for a given variable.

Usage

local_g(x, nb, wt, alternative = "two.sided", ...)

local_g_perm(x, nb, wt, nsim = 499, alternative = "two.sided", ...)

Arguments

x	A numeric vector.
nb	a neighbor list object for example as created by st_contiguity().
wt	a weights list as created by st_weights().
alternative	default "two.sided". Should be one of "greater", "less", or "two.sided" to specify the alternative hypothesis.
...	methods passed to spdep::localG() or spdep::localG_perm()
nsim	The number of simulations to run.

Value

a data.frame with columns:

• gi: the observed statistic

• cluster: factor variable with two levels classification high or low

• e_gi: the permutation sample mean

• var_gi: the permutation sample variance

• std_dev: standard deviation of the Gi statistic

• p_value: the p-value using sample mean and standard deviation

• p_folded_sim: p-value based on the implementation of Pysal which always assumes a two-sided test taking the minimum possible p-value

• skewness: sample skewness

• kurtosis: sample kurtosis

Examples

x <- guerry$crime_pers
nb <- st_contiguity(guerry)
wt <- st_weights(nb)

res <- local_g_perm(x, nb, wt)

head(res)

sfdep documentation built on Sept. 13, 2024, 5:07 p.m.