Answer Happy

3 A sales manager collected the following data on annual sales for new customer accounts and the number of years of experience for a sample of 9 salespersons. Salesperson Years of experience Annual Sales ($1000s) 1 1 80 2 3 97 4 92 4 102 103 6 111 7 10 119 10 123 11 113 4 00 VOU AWN in 5 6 8 8 9 a. Develop an estimated regression equation that can be used to predict annual sales given the years of experience. (10) b. Compute SST, SSR, SSE, the coefficient of determination r2, and the value of the sample correlation coefficient. (5*2') c. Perform a hypothesis test to examine whether the coefficient of years of experience is different from 0 at 5% significance level, using t test. You need to report the hypotheses tests (2'), test statistics (5'), p-value or critical value (5"), and the conclusion (2'). (14' in total) d. Perform a hypothesis test to examine whether the coefficient of years of experience is different from 0 at 5% significance level, using F test. You need to report the hypotheses tests (2'), test statistics (5'), p-value or critical value (5'), and the conclusion (2"). (14' in total) e. Do you reach the same conclusion in parts c and d? (2") f. Use the estimated regression equation to predict annual sales for a salesperson with 10 years of experience. (5') g. Compute the residuals and construct a residual plot for this problem. (10') h. Do the assumptions about the error terms seem reasonable in light of the residual plot? (5')