6. When Blanchard shows your new regression to Tyler she gripes about the low R-Squared. She...

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6. When Blanchard shows your new regression to Tyler she gripes about the "low" R-Squared. She suggests that you include three new dummy variables in your data set, namely dummies for Weeks 7, 21, and 49. (For example, the dummy for Week 7 is 1 for the two data points from Week 7 of a year and 0 for all other weeks.) Tyler believes that these new dummy variables "will increase the R-squared and make the regression more meaningful and the resulting predictions much better." a. Drop again all variable from your regression that do not meet Tyler's desired level of significance. Report your final regression equation. b. Are the coefficients of the new dummy variables significant? What is the new R-squared? c. Provide a simple and intuitive explanation for the effect of the three new variables. d. Do you believe that the new regression will yield better predictions than your previous regression? Comment on Tyler's arguments in favor of the new variables 7. Blanchard believe your analysis for question 5 does not properly account for the effects of the advertising variables. He argues that TV GRPs and radio GRPs affect c-store sales differently during weeks with holiday than during weeks with no holidays. In particular, he believes that TV and radio advertising have a significantly larger influence on c-store sales in weeks without holidays than in holiday weeks. Modify your regression from question 5 to address Blanchards concerts. Can you prove his claims? 6. When Blanchard shows your new regression to Tyler she gripes about the "low" R-Squared. She suggests that you include three new dummy variables in your data set, namely dummies for Weeks 7, 21, and 49. (For example, the dummy for Week 7 is 1 for the two data points from Week 7 of a year and 0 for all other weeks.) Tyler believes that these new dummy variables "will increase the R-squared and make the regression more meaningful and the resulting predictions much better." a. Drop again all variable from your regression that do not meet Tyler's desired level of significance. Report your final regression equation. b. Are the coefficients of the new dummy variables significant? What is the new R-squared? c. Provide a simple and intuitive explanation for the effect of the three new variables. d. Do you believe that the new regression will yield better predictions than your previous regression? Comment on Tyler's arguments in favor of the new variables 7. Blanchard believe your analysis for question 5 does not properly account for the effects of the advertising variables. He argues that TV GRPs and radio GRPs affect c-store sales differently during weeks with holiday than during weeks with no holidays. In particular, he believes that TV and radio advertising have a significantly larger influence on c-store sales in weeks without holidays than in holiday weeks. Modify your regression from question 5 to address Blanchards concerts. Can you prove his claims?