Corporation owns several companies. Strategic planner for corporation believes dollars spent on advertising can to some extent be the predictor of total sales dollars. As the aid in long-term planning, she collects the following sales and advertising information from twelve of companies for 2011 (in $ millions). Solve by excel and by mega stat
ADVERTISING SALES
12.5 148
3.7 55
21.6 338
60.0 994
37.6 541
6.1 89
16.8 126
41.2 379
18.4 232
26.3 312
48.7 442
58.4 513
1) Is regression statistically significant? Let α = .05. What do you conclude?
2) Point to the regression equation. If x = 40 what is an estimate for y.
3) Determine the Standard Error of the Estimate, Se.
4) Compute the 95% confidence and prediction intervals for values of y for X = 40.
5) Determine correlation coefficient, Interpret.
6) Compute coefficient of determination, Interpret.
7) Verify the coefficient of determination from the ANOVA table values.
8) Verify the standard error of the estimate from the ANOVA table values.