gearyc.boot: Generate Bootstrap Replicates of Geary's C Autocorrelation...

In DCluster: Functions for the Detection of Spatial Clusters of Diseases

Generate Bootstrap Replicates of Geary's C Autocorrelation Statistic

Description

Generate bootstrap replicates of Geary's C autocorrelation statistic, by means of function boot form boot library. Notice that these functions should not be used separately but as argument statistic when calling function boot.

gearyc.boot is used when performing a non-parametric bootstrap.

gearyc.pboot is used when performing a parametric bootstrap.

Usage

gearyc.boot(data, i, ...)
gearyc.pboot(...)

Arguments

data	A dataframe containing the data, as specified in the DClustermanpage.
i	Permutation generated by the bootstrap procedure
...	Aditional arguments passed when performing a bootstrap.

Value

Both functions return the value of the statistic.

References

Geary, R. C. (1954). The contiguity ratio and statistical mapping. The Incorporated Statistician 5, 115-145.

See Also

DCluster, boot, gearyc, gearyc.stat

Examples

library(boot)
library(spdep)

data(nc.sids)
col.W <- nb2listw(ncCR85.nb, zero.policy=TRUE)

sids<-data.frame(Observed=nc.sids$SID74)
sids<-cbind(sids, Expected=nc.sids$BIR74*sum(nc.sids$SID74)/sum(nc.sids$BIR74))


niter<-100

#Permutation model
gc.perboot<-boot(sids, statistic=gearyc.boot, R=niter, listw=col.W,
	n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) )
plot(gc.perboot)#Display results

#Multinomial model
gc.mboot<-boot(sids, statistic=gearyc.pboot, sim="parametric", 
	ran.gen=multinom.sim, R=niter, listw=col.W,
        n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) )
plot(gc.mboot)#Display results

#Poisson model
gc.pboot<-boot(sids, statistic=gearyc.pboot, sim="parametric", 
	ran.gen=poisson.sim, R=niter, listw=col.W,
	n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) )
plot(gc.pboot)#Display results

#Poisson-Gamma model
gc.pgboot<-boot(sids, statistic=gearyc.pboot, sim="parametric", 
	ran.gen=negbin.sim, R=niter, listw=col.W,
	n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) )
plot(gc.pgboot)#Display results

DCluster documentation built on May 29, 2024, 3:41 a.m.