This video features the second half of our coverage of Example 9 in Mod13Script.R.  You should open this script in RStudio and follow along while watching. Here we we consider adding quadratic terms and interactions to our model, illustrate the testing of nested models, show how to extract results from a fitted linear model object, show how to produce predictions and pointwise confidence or prediction intervals from a fitted model, and plot a fitted regression model with two predictors.

This video is essential content for the course.