#  R CODE TO DRAW BETA(a,b) DENSITIES FOR a,b = 1,2,3,4:

x<-seq(0,1,length=101)

par(mfrow=c(4,4))

for (i in 1:4){
  for (j in 1:4){
plot(x,dbeta(x,i,j),type="l",xlab="p",ylab="density",
  ylim=c(0,4))
title(paste("Beta(",i,",",j,")"))
}}