Homework SourseResearchers randomly assigned 33 participants suffering from
Researchers randomly assigned 33 participants suffering from generalized anxiety disorder (GAD) to the three levels of a treatment IV (cognitive behavioral, group therapy, and no treatment control) and measured outcome by administering a measure of anxiety that ranged in total score from 1 to 50 with higher scores indicating more anxiety. When the researchers analyzed the data, they obtained the following ANOVA summary table with certain values missing. To answer questions pertaining to these data, you will need to solve for the missing values.
Source
df
SS
MS
F
Treatment
2
?
1100
?
?
2700
?
32
4900
What is df(error) in this ANOVA summary table?
| Source | df | SS | MS | F |
| Treatment | 2 | ? | 1100 | ? |
| Error | ? | 2700 | ? | |
| Total | 32 | 4900 |
Solution
Complete the summary table:
Source
df
SS
MS
F
Treatment
2
4900-2700=2200
1100
1100/90=12.22
Error
32-2=30
2700
2700/30=90
Total
32
4900
The df(error)=32-2=30
| Source | df | SS | MS | F |
| Treatment | 2 | 4900-2700=2200 | 1100 | 1100/90=12.22 |
| Error | 32-2=30 | 2700 | 2700/30=90 | |
| Total | 32 | 4900 |
