R/twobinom.R

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

twobinom <-
function(r1=sum(elimna(x)),n1=length(x),r2=sum(elimna(y)),n2=length(y),x=NA,y=NA,alpha=.05){
#
# Test the hypothesis that two independent binomials have equal
# probability of success
#
# r1=number of successes in group 1
# n1=number of observations in group 1
#
n1p<-n1+1
n2p<-n2+1
n1m<-n1-1
n2m<-n2-1
chk<-abs(r1/n1-r2/n2)
x<-c(0:n1)/n1
y<-c(0:n2)/n2
phat<-(r1+r2)/(n1+n2)
m1<-outer(x,y,"-")
m2<-matrix(1,n1p,n2p)
flag<-(abs(m1)>=chk)
m3<-m2*flag
b1<-1
b2<-1
xv<-c(1:n1)
yv<-c(1:n2)
xv1<-n1-xv+1
yv1<-n2-yv+1
dis1<-c(1,pbeta(phat,xv,xv1))
dis2<-c(1,pbeta(phat,yv,yv1))
pd1<-NA
pd2<-NA
for(i in 1:n1)pd1[i]<-dis1[i]-dis1[i+1]
for(i in 1:n2)pd2[i]<-dis2[i]-dis2[i+1]
pd1[n1p]<-phat^n1
pd2[n2p]<-phat^n2
m4<-outer(pd1,pd2,"*")
test<-sum(m3*m4)
list(p.value=test,p1=r1/n1,p2=r2/n2,est.dif=r1/n1-r2/n2)
}