source('../../Data/get_birthwt_data.R')
DF = get_birthwt_data()

m = lm(wt ~ length, data=DF)
print(summary(m))

par(mfrow=c(2, 1))
plot(DF$length, DF$wt, 'p', pch=19, xlab='Length', ylab='Weight')
abline(m)
abline(h=1500, col='red') ## the largest a "low-birth-weight" babie can be 
grid()

plot(fitted(m), residuals(m), 'p', pch=19, xlab='Fitted Values', ylab='Residuals')
abline(h=0, col='black')
grid()
par(mfrow=c(1, 1))