Use the following data set for Exercises 27–33. Note that is a dummy variable.
−0.7 | 2 | 0.1 | 0 |
6.4 | 4 | −2.5 | 1 |
2.8 | 6 | 2.7 | 0 |
9.4 | 8 | 2.8 | 1 |
8.6 | 10 | −1.6 | 0 |
13.1 | 12 | 1.0 | 1 |
12.2 | 14 | −1.4 | 0 |
19.1 | 16 | −0.5 | 1 |
18.8 | 18 | 1.0 | 0 |
23.2 | 20 | −2.3 | 1 |
33. Report and interpret your final model from Exercise 31, by doing the following:
13.3.33
(a) The final multiple regression equation is . For , the regression equation is . For , the regression equation is . (b) For each increase in one unit of the variable , the estimated value of increases by 1.15 units. The estimated increase in for those observations with , as compared to those with , when is held constant, is 3.61. (c) Using the multiple regression equation in (a), the size of the typical prediction error will be about 0.959129. 98.4% of the variability in is accounted for by this multiple regression equation.