How productive are U.S. workers? One way to answer this questionis to study annual profits per employee. A random sample ofcompanies in computers (I), aerospace (II), heavy equipment (III),and broadcasting (IV) gave the following data regarding annualprofits per employee (units in thousands of dollars).
| I | II | III | IV |
| 27.5 | 13.7 | 22.8 | 17.1 |
| 23.3 | 9.3 | 20.3 | 16.7 |
| 14.7 | 11.7 | 7.9 | 14.5 |
| 8.6 | 8.9 | 12.5 | 15.3 |
| 11.5 | 6.1 | 7.2 | 10.4 |
| 19.2 | | 9.1 |
Shall we reject or not reject the claim that there is nodifference in population mean annual profits per employee in eachof the four types of companies? Use a 5% level of significance.
(b) Find SSTOT, SSBET, andSSW and check that SSTOT =SSBET + SSW. (Use 3 decimal places.)
Find d.f.BET, d.f.W,MSBET, and MSW. (Use 3 decimalplaces for MSBET, andMSW.)
Find the value of the sample F statistic. (Use 3 decimalplaces.)
What are the degrees of freedom?
(numerator)=
(denominator)=
(f) Make a summary table for your ANOVA test.
Source of
Variation | Sum of
Squares | Degrees of
Freedom | MS | F
Ratio | P Value | Test
Decision |
| Between groups | | | | | ---Select--- p-value > 0.100 0.050 < p-value < 0.1000.025 < p-value < 0.050 0.010 < p-value < 0.025 0.001< p-value < 0.010 p-value < 0.001 | ---Select--- Do not reject H0. Reject H0. |
| Within groups | | | | | | |
| Total | | | | | | |
