Find the regression equation; unless the problem suggests otherwise, let the first variable be the independent (x) variable. Caution: When finding predicted values, be sure to follow the prediction procedure described in this section.
Refer to Data Set 21 in Appendix B.
a. Use the paired data consisting of price and carat (weight). What is the best predicted price of a diamond with a weight of 1.5 carats?
b. Use the paired price/colour data. Assuming the colour data is recorded in an interval scale, what is the best predicted price of a diamond with a colour rating of 3?
c. Which prediction is better, the result from part (a) or the result from part (b)? Why?