Savings <- read.table('http://math.uttyler.edu/nathan/classes/grad-statistics/data/savings.data',
                      header=TRUE)
attach(Savings)

mod <- lm(sr ~ pop75 + dpi)
summary(mod)

data.frame(sr,pop75,dpi)

my.bogus.dataset <- data.frame(sr,sample(pop75),dpi)
names(my.bogus.dataset)[2] <- 'pop75'

data.frame(sr,pop75,dpi,my.bogus.dataset)

bogus.mod <- lm(sr ~ pop75 + dpi,data=my.bogus.dataset)
summary(bogus.mod)$coefficients
summary(mod)$fstatistic[1]

f.stats <- replicate(2000,summary(lm(sample(sr)~pop75+dpi))$fstatistic[1])
length(f.stats[f.stats>2.679647])
185/2000