This problem demonstrates a possible (though rare) situation that can occur with group comparisons. The groups are sections and the dependent variable is an exam score. Section 1 Section 2 Section 3 74.5 69.7 85.4 85.1 72.5 82.9 80.3 45.7 78.8 88.8 84.4 79.4 66.4 62.4 68 72.5 48.3 78 83.1 88 69.7 79.4 61.5 76.2 71.4 67.3 74.9 Run a one-factor ANOVA (fixed effect) with α=0.05α=0.05. Report the F-ratio to 3 decimal places and the P-value to 4 decimal places. F=F= Correct p=p= Correct What is the conclusion from the ANOVA? reject the null hypothesis: at least one of the group means is different fail to reject the null hypothesis: not enough evidence to suggest the group means are different Correct
This problem demonstrates a possible (though rare) situation that can occur with group comparisons. The groups are sections and the dependent variable is an exam score.
| Section 1 | Section 2 | Section 3 |
|---|---|---|
| 74.5 | 69.7 | 85.4 |
| 85.1 | 72.5 | 82.9 |
| 80.3 | 45.7 | 78.8 |
| 88.8 | 84.4 | 79.4 |
| 66.4 | 62.4 | 68 |
| 72.5 | 48.3 | 78 |
| 83.1 | 88 | 69.7 |
| 79.4 | 61.5 | 76.2 |
| 71.4 | 67.3 | 74.9 |
Run a one-factor ANOVA (fixed effect) with α=0.05α=0.05. Report the F-ratio to 3 decimal places and the P-value to 4 decimal places.
F=F= Correct
p=p= Correct
What is the conclusion from the ANOVA?
- reject the null hypothesis: at least one of the group means is different
- fail to reject the null hypothesis: not enough evidence to suggest the group means are different
Calculate the group means for each section:
Section 1: M1=M1= Correct
Section 2: M2=M2= Correct
Section 3: M3=M3= Correct
Report means accurate to 2 decimal places.
Conduct 3 independent sample t-tests for each possible pair of sections. (Though we will see later that it might not be appropriate, retain the significance level α=0.05α=0.05.) Report the P-value (accurate to 4 decimal places) for each pairwise comparison.
Compare sections 1 & 2: p=p= Incorrect
Compare sections 1 & 3: p=p= Incorrect
Compare sections 2 & 3: p=p= Incorrect
Based on these comparisons, which pair of groups have statistically significantly different means?
- group 1 mean is statistically different from group 2 mean
- group 1 mean is statistically different from group 3 mean
- group 2 mean is statistically different from group 3 mean
- none of the group means are statistically significantly different from each other
Trending now
This is a popular solution!
Step by step
Solved in 4 steps with 3 images
