Note Your answers to the questions below should follow the expectations for homework found here. Due date is on the Dates page.

Car Horsepower and Gas Mileage II

1993 Car Students in the Introduction to Environmental Studies course were interested in what characteristics of cars affected the gas mileage (miles per gallon) of a car. Using an internet search they recorded several variables on a sample of makes of cars (note that these data are industry-reported summaries for the make of a car, not measurements on an individual car). Two of the variables that they recorded were mpg (miles per gallon of gasoline for the car) and hp (horsepower of the car engine). These data, along with many other variables are in CarMPG.csv (download, meta). Use these data to compute a model that can be used to predict the mpg of a car from its horsepower.

  1. Assess the independence assumption.
  2. Thoroughly test the linearity assumption.
  3. Thoroughly test the homoscedasticity assumption.
  4. Thoroughly (use all possible options) test the normality assumption.
  5. Thoroughly (use all possible options) test the outliers assumption.