pdf("ex0402.pdf")

# Read in data from ASCII formatted (Fixed With File)

ex0402dat <- read.fwf("http://www.stat.ufl.edu/~winner/data/biostat/ex0402.dat", width=c(8,8), col.names=c("group","bioavail"))

# Create a dataset (frame) from input data 

attach(ex0402dat)

# Conduct the independent sample t-test comparing healthy (group=1) and pre-transplant (group=2)
#   subjects assuming equal variances 

t.test(bioavail~group, var.equal=T)

# Conduct the independent sample t-test comparing healthy (group=1) and pre-transplant (group=2)
#   subjects NOT assuming equal variances 

t.test(bioavail~group)

dev.off()