Using the XR17-07 dataset (in the data sets/Excel files directory of the CD accompanying your textbook) and Microsoft Excel, build and validate a multiple regression model. Explicitly describe the following: "c Choose the dependent as well as the independent variables. Why do you think are the selected independent variables expected to cause changes in the dependent variables? "c Assess the goodness of fit of your model. "c Interpret the coefficients of the regression model. Which independent variable has the strongest impact on the dependent variables? Which independent variable has the weakest impact? "c Summarize the key business takeaways from your model. Briefly describe what the model communicates.
| Sales |
Direct |
Newspaper |
Television |
| 15.98 |
1.05 |
1.35 |
1.55 |
| 21.59 |
1.29 |
2.25 |
1.97 |
| 25.47 |
0.96 |
1.79 |
1.64 |
| 16.02 |
1.51 |
1.73 |
1.73 |
| 16.58 |
1.30 |
1.71 |
1.61 |
| 20.10 |
1.06 |
1.61 |
1.82 |
| 17.49 |
0.86 |
1.62 |
1.97 |
| 22.53 |
0.78 |
2.20 |
1.61 |
| 23.98 |
1.20 |
1.77 |
1.13 |
| 18.96 |
0.83 |
1.17 |
1.77 |
| 24.64 |
1.01 |
1.76 |
2.04 |
| 19.52 |
1.34 |
1.81 |
1.63 |
| 19.97 |
0.55 |
2.25 |
1.93 |
| 18.86 |
1.06 |
1.98 |
1.63 |
| 22.79 |
0.90 |
1.54 |
2.27 |
| 20.38 |
1.88 |
1.15 |
1.45 |
| 16.51 |
0.51 |
1.19 |
1.93 |
| 18.32 |
0.53 |
1.75 |
1.44 |
| 16.04 |
1.21 |
1.01 |
1.46 |
| 18.91 |
0.90 |
1.68 |
1.66 |
| 20.09 |
0.97 |
1.72 |
1.59 |
| 19.83 |
1.01 |
1.72 |
1.42 |
| 18.42 |
1.29 |
1.47 |
2.05 |
| 21.99 |
1.35 |
1.94 |
2.28 |
| 20.57 |
1.07 |
2.31 |
1.77 |