#  2004 年 12 月 21 日作成
# simulation of CLT from Poisson sample
num.rep<-10000
num.sample<-10
quasai.ram<-rep(0,num.rep)
for (i in 1:num.rep){
quasai.ram[i]<-sqrt(num.sam)*(mean(rpois(num.sample,1)-1)
}
#
# drat graph of centered sample mean 
#
plot(density(qusai.ran),xlim=c(-4,4),ylim=c(0,0.5),type="l")
#
# drat graph of standard normal
#
xx<-seq(-4,4,by=0.001)
par(new=T)
plot(xx,dnorm(xx,0,1),xlim=c(-4,4),ylim=c(0,0.5),type="l")