The scatterplot below shows the relationship between the number of calories and amount of carbohydrates (in grams) Starbucks food menu items contain. Since Starbucks only lists the number of calories on the display items, we are interested in predicting the amount of carbs a menu item has based on its calorie content. Examine the accompanying scatterplot (left) and residual plot (middle) and residual histogram (right). Does it seem as though the OLS model is appropriate, or does it fail? If it fails, on which condition? (see image - starbucks_menu)
A. Passes all three, and using an OLS model is appropriate
B. Fails on Linearity (#1)
C. Fails on Nearly Normal Residuals (#2)
D. Fails on Constant Variability (#3)
E. Fails on #1 and #2
F. Fails on #2 and #3
G. Fails on #1 and #3
H. Fails on all three
A small p-value (i.e. statistically significant) sometimes, but not always, is linked to a practically useful effect (practical significance).
A. True
B. False