source("http://192.38.117.59/~linearpredictors/datafiles/readVitaminD.R")

## Linear regression of Vitamin D on BMI
model <- lm(irlwomen$vitd~irlwomen$bmi)

## Scatter plot with regression line
plot(vitd ~ bmi,
     data = irlwomen,
     ylab = "Vitamin D",
     xlab = "BMI")

lines(model$fitted ~ irlwomen$bmi)

## Dashed lines indicating distances from observations to the regression line
m <- model$model
segments(m$"irlwomen$bmi",
         m$"irlwomen$vitd",
         m$"irlwomen$bmi",
         m$"irlwomen$vitd" - model$residuals,
         lty = "32")