{

#test=matrix(scan("hel34"),ncol=2,byrow=T)

xx=scan("hel55")

N = length(xx)

#generate nsim bootstrap samples
nsim = 500

#statistics desired..
meansim = 1:nsim
varsim = 1:nsim
mediansim = 1:nsim

for(i in 1:nsim){

xsamp = sample(xx, N, replace=TRUE)

meansim[i]=mean(xsamp)
varsim[i]=var(xsamp)
mediansim[i]=median(xsamp)

}


# Confidence interval on the population mean
# assuming the data is Normally distributed
alpha = 0.05		#confidence level
alpha2 = alpha/2

print(c(quantile(meansim, c(alpha2, 1-alpha2))))

print(c(quantile(varsim, c(alpha2, 1-alpha2))))
print(c(quantile(mediansim, c(alpha2, 1-alpha2))))

}