Topic 10 Multiple Regression Reading from the book: Chapter 12 and Chapter 13: section 13.5 e-book: Chapter 14, pages 469-488 Assignment for Topic 10: Exercise: This exercise continues from the Exercise in Topic 9. The marketing manager of a chain of stores needed more information about the effectiveness of the three types of advertising that the chain used: television advertising, direct mailing and newspaper advertising. The manager collected data from 25 randomly selected stores. For each store, the following variables were recorded per week: store sales, TV advertising, Direct mailing and Newspaper advertising. All variables are recorded in thousands of euros (i.e. 1 unit=1000). You enter all the independent variables. You can see PART of the data below. The SPSS output follows. Sales TV Direct Newspaper 17.49 0.86 1.62 1.97 22.53 0.78 2.2 1.61 23.98 1.20 1.77 1.13 18.96 0.83 1.17 1.77 24.64 1.91 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 Notes written by Dr. Haritini Tsangari for MBA-603 Std. Error of the Model R 1 R Square .618 Adjusted R Square .382 Estimate .294 2.26713 ANOVA Model 1 Sum of Squares Regression df Mean Square 66.726 3 22.242 Residual 107.937 21 174.663 Sig. 5.140 Total F 4.327 24 Coefficients Standardized Unstandardized Coefficients Model B Std. Error (Constant) 10.629 2.869 1.126 Direct 3.012 .522 Beta t 3.623 Television Coefficients Newspaper Sig. 2.934 .008 .439 2.548 .019 1.342 .390 2.244 .036 1.707 .053 .306 .763 Answer the following questions: (1) Do an overall F test and write your conclusions. (2) According to your result of part (1) continue further to test individually which variables are significant for the model. (3) Write down the final estimated model and interpret the coefficients. (4) Is the final model better than the model which included only television advertising as an independent variable? Explain. (5) Using your model estimate the weekly sales for a store that spends 1200 on TV advertising, 1770 on direct mailing and 1130 on newspaper advertising. Notes written by Dr. Haritini Tsangari for MBA-603 .016