A corporation owns several companies. The strategic planner for the corporation believes dollars spent on advertising can to some extent be a predictor of total sales dollars. As an aid in long-term planning, she gathers the following sales and advertising information from twelve of the 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 the regression statistically significant? Let α = .05. What do you conclude?
2) Indicate the regression equation. If x = 40 what is an estimate for y.
3) What is the Standard Error of the Estimate, Se.
4) What is the 95% confidence and prediction intervals for the values of y for X = 40.
5) What is the correlation coefficient, Interpret.
6) What is the coefficient of determination, Interpret.
7) Verify the coefficient of determination from the ANOVA table values. ( Do the calculation)
8) Verify the standard error of the estimate from the ANOVA table values.