MATH 315 Quiz 02

Due 2025-11-21 by 11:59pm

1. Load the dataset on carnivora. Our goal is to predict brain weight SB (grams) using body weight SW (kilograms). Assume a level of significance of 0.05.

   a. Perform step 1 of any regression analysis, using ggplot2. Describe the assocation of these variables.

   b. Redo the plot above, now adding geom_smooth(...) and the formula y ~ poly(x, 2).

   c. Fit a quadratic model, where the explanatory variable is squared; you'll use poly(..., 2) again now inside lm(...).

   d. Report and interpret in context of the data adjusted .

   e. Compare from this model to the you got from the log10 transformed model. Which model predicts brain weight SB better?