1\name{gearyc.boot} 2 3\alias{gearyc.boot} 4\alias{gearyc.pboot} 5 6\title{Generate Bootstrap Replicates of Geary's C Autocorrelation Statistic} 7 8 9\description{ 10Generate bootstrap replicates of Geary's C autocorrelation statistic, by means 11of function \emph{boot} form \emph{boot} library. Notice that these functions 12should not be used separately but as argument \emph{statistic} when calling 13function \emph{boot}. 14 15\emph{gearyc.boot} is used when performing a non-parametric bootstrap. 16 17\emph{gearyc.pboot} is used when performing a parametric bootstrap. 18} 19 20 21\usage{ 22gearyc.boot(data, i, ...) 23gearyc.pboot(...) 24} 25 26\arguments{ 27\item{data}{A dataframe containing the data, as specified in the 28\bold{DCluster}manpage.} 29\item{i}{Permutation generated by the bootstrap procedure} 30\item{...}{Aditional arguments passed when performing a bootstrap.} 31} 32 33\value{ 34Both functions return the value of the statistic. 35} 36 37\seealso{ 38DCluster, boot, gearyc, gearyc.stat 39} 40 41 42\examples{ 43library(boot) 44library(spdep) 45 46data(nc.sids) 47col.W <- nb2listw(ncCR85.nb, zero.policy=TRUE) 48 49sids<-data.frame(Observed=nc.sids$SID74) 50sids<-cbind(sids, Expected=nc.sids$BIR74*sum(nc.sids$SID74)/sum(nc.sids$BIR74)) 51 52 53niter<-100 54 55#Permutation model 56gc.perboot<-boot(sids, statistic=gearyc.boot, R=niter, listw=col.W, 57 n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) ) 58plot(gc.perboot)#Display results 59 60#Multinomial model 61gc.mboot<-boot(sids, statistic=gearyc.pboot, sim="parametric", 62 ran.gen=multinom.sim, R=niter, listw=col.W, 63 n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) ) 64plot(gc.mboot)#Display results 65 66#Poisson model 67gc.pboot<-boot(sids, statistic=gearyc.pboot, sim="parametric", 68 ran.gen=poisson.sim, R=niter, listw=col.W, 69 n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) ) 70plot(gc.pboot)#Display results 71 72#Poisson-Gamma model 73gc.pgboot<-boot(sids, statistic=gearyc.pboot, sim="parametric", 74 ran.gen=negbin.sim, R=niter, listw=col.W, 75 n=length(ncCR85.nb), n1=length(ncCR85.nb)-1, S0=Szero(col.W) ) 76plot(gc.pgboot)#Display results 77 78} 79 80\references{ 81Geary, R. C. (1954). The contiguity ratio and statistical mapping. The Incorporated Statistician 5, 115-145. 82} 83 84\keyword{spatial} 85