R/t2waybt.R

In musto101/wilcox_R: What the package does (short line)

t2waybt <-
function(J,K,x,tr=.2,grp=c(1:p),p=J*K,nboot=599,SEED=TRUE){
#
#   Two-way ANOVA based on trimmed means and a bootstrap-t method
#
#   The data are assumed to be stored as described in the function t2way
#
#   The default number of bootstrap samples is nboot=599
#
if(is.data.frame(x))x=as.matrix(x)
if(is.matrix(x))x<-listm(x)
if(!is.list(x))stop("Data must be stored in a matrix or in list mode.")
if(SEED)set.seed(2) # set seed of random number generator so that
#             results can be duplicated.
# compute test statistics:
tests=t2way.no.p(J=J,K=K,x,tr=tr,grp=grp)
TA=NULL
TB=NULL
TAB=NULL
data=list()
xcen=list()
for(j in 1:length(x))xcen[[j]]<-x[[j]]-mean(x[[j]],tr)
print("Taking bootstrap samples. Please wait.")
for(b in 1:nboot){
for(j in 1:length(x))data[[j]]<-sample(xcen[[j]],size=length(x[[j]]),replace=TRUE)
bt=t2way.no.p(J,K,data,tr=tr,grp=grp)
TA[b]=bt$Qa
TB[b]=bt$Qb
TAB[b]=bt$Qab
}
pA<-sum(tests$Qa<=TA)/nboot
pB<-sum(tests$Qb<=TB)/nboot
pAB<-sum(tests$Qab<=TAB)/nboot
list(A.p.value=pA,B.p.value=pB,AB.p.value=pAB)
}