1. Perform a two-way analysis of variance of Rating by Vehicle Type and Manufacturer. Use economy cars from the United States as the baseline group.
(a) Summarize your model.
(b) Show a profile plot of the estimated model. Does the profile plot suggest the presence of an interaction?
(c) Are these data compatible with the assump- tions of an ANOVA regression?
(d) If appropriate, which effects are statistically significant?
2. Show that the estimated rating from the model for premium cars from Asia matches the aver- age rating of cars in this group.