pdf("g12.pdf");options(width=64)
#setwd("C:\\Users\\kolassa\\Class555")
setwd("~/Taught1/960-555/Data")
<pre>
#*************************************************************/
# Data from http://lib.stat.cmu.edu/datasets/Arsenic         */
# reformatted into ASCII on the course home page.  Data re-  */
# flect arsenic levels in toenail clippings; covariates in-  */
# clude age, sex (1=M), categorical measures of quantities   */
# used for drinking and cooking, arsenic in the water, and   */
# arsenic in the nails.  To make arsenic.dat from Arsenic, do*/
#antiword Arsenic|awk '((NR>39)&&(NR<61)){print}'>arsenic.dat*/
#*************************************************************/
arsenic<-read.table("arsenic.dat")
names(arsenic)<-c("age","sex","drink","cook","water",
   "nails")
arsenic$status<-(arsenic$water>=.0001)+0
arsenic$water[arsenic$water<.0001]<-.0001
arsenic$lnail<-log(arsenic$nails)
arsenic$lwater<-log(arsenic$water)
#<a name=block1> Block 1</a>
meds<-rep(NA,999)
for(j in seq(length(meds)))
   meds[j]<-median(sample(arsenic$nails,length(arsenic$nails),
      replace=TRUE))
#<a name=block2> Block 2</a>
cat(ci<-quantile(meds,probs=c(.025,.975)),"\n")
#<a name=block3> Block 3</a>
cat('\n Residual Bootstrap for Median\n')
cat(ci<-2*median(arsenic$nails)-rev(ci),"\n")
</pre>