Homework SourseAn article gives adaptation scores for three different treat
An article gives adaptation scores for three different treatments: (1) no shock, (2) shock following each stuttered word, and (3) shock during each moment of stuttering. These treatments were used on each of 18 stutterers, resulting in
SST = 3471.00, SSTr = 27.78, and SSBl = 2979.61.
(a) Construct the ANOVA table and test at level 0.05 to see whether true average adaptation score depends on the treatment given. State the appropriate hypotheses.
Complete the AVOVA table. (Round your answers to two decimal places.)
State the conclusion in the problem context.
Judging from the F ratio for subjects (factor B), do you think that blocking on subjects was effective in this experiment? Explain.
| Source | df | SS | MS | f | F0.05 |
|---|---|---|---|---|---|
| Treatments | |||||
| Blocks | |||||
| Error | |||||
| Total |
Solution
There are three treatments so degree of freedom of treatments is 3-1=2
There are 18 blocks so degree of freedom of blocks is 18-1=17
Since there are total 18*3=54 observations so total degree of freedom is df=54-1=53
Degree of freedom of error is 53-17-2=34
Since fB > 1.9332, reject H0.
| Source | df | SS | MS | f | F (0.05) |
| Treatments | 2 | 27.78 | (27.78/2)=13.89 | fA=(13.89/15.78)=0.8802 | 3.2759 |
| Blocks | 17 | 2979.61 | (2979.61/17)=175.27 | fB=(175.27/15.78)=11.11 | 1.9332 |
| Error | 34 | 3471-(2979.61+27.78)=536.39 | (536.39/34)=15.78 |
