To test whether students in a higher grade level will be lessdisruptive in class, a school psychologist records the number ofdocumented interruptions during one day of classes from nine localhigh schools. The sample consisted of nine
(n = 9)
freshman, sophomore, junior, and senior high school classes. Thedata for each high school class are given in the table.
High School Class |
Freshman | Sophomore | Junior | Senior |
1 | 0 | 3 | 4 |
2 | 5 | 6 | 1 |
4 | 1 | 0 | 3 |
0 | 4 | 4 | 2 |
1 | 1 | 5 | 4 |
3 | 0 | 0 | 4 |
5 | 2 | 3 | 2 |
2 | 5 | 5 | 4 |
4 | 3 | 4 | 5 |
(a) Complete the F-table. (Round your answers to twodecimal places.)
Source of
Variation | SS | df | MS | F |
Between
groups | | | | |
Within
groups (error) | | | | |
Total | | | | |
(b) Is it necessary to compute a post hoc test? Explain. (Assumealpha equal to 0.05.)
Yes, post hoc analyses are appropriate because the ANOVA issignificant.
No, post hoc analyses are not appropriate because the ANOVA isnot significant.
You may need to use the appropriate table in Appendix B to answerthis question.
