Homework SourseComputer 1 Computer 2 Computer 3 Control 550 666 700 400 220
Computer 1
Computer 2
Computer 3
Control
550
666
700
400
220
350
650
500
300
363
500
300
600
400
450
550
According to the data above the statistically significant value is (answer in three significant figures) and is there a statistically significant difference between computers 1, 2, and 3, (yes or no)?
| Computer 1 | Computer 2 | Computer 3 | Control |
| 550 | 666 | 700 | 400 |
| 220 | 350 | 650 | 500 |
| 300 | 363 | 500 | 300 |
| 600 | 400 | 450 | 550 |
Solution
Sol)
Null Hypothesis: There is no difference between the means of three computers
Alternative Hypothesis: There is no difference between the means of three computers
level of significance:u alpha=5%
Test Statistic:
To test the homogenity of several means we use ANOVA one way(F-Test)
From Excel
Conclusion:
F cal=1.198 and F critical value at 5% level is 4.2564
F cal < F crritical value, Then we Accept the null hypothesis.
There is no difference between the means of three computers
| Anova: Single Factor | ||||||
| SUMMARY | ||||||
| Groups | Count | Sum | Average | Variance | ||
| Computer 1 | 4 | 1670 | 417.5 | 34558.33 | ||
| Computer 2 | 4 | 1779 | 444.75 | 22204.92 | ||
| Computer 3 | 4 | 2300 | 575 | 14166.67 | ||
| ANOVA | ||||||
| Source of Variation | SS | df | MS | F | P-value | F crit |
| Between Groups | 56685.17 | 2 | 28342.58 | 1.198757 | 0.345498 | 4.256495 |
| Within Groups | 212789.8 | 9 | 23643.31 | |||
| Total | 269474.9 | 11 |
