More on ANOVA
Within-Subjects ANOVA
Answers
- Trial, Dose, and Day. If different groups are used for each condition,
then the variable is a between-subjects variable; if the same subjects
are tested in
each condition, then the variable is a within-subjects variable.
- For between-subjects variables, differences among subjects are error.
For within-subjects variables, each subject's performance in one
condition is compared to his or her performance
in another condition. Therefore, overall differences are not a source
of error.
- The assumption has to do with correlations among scores, which is not
applicable in between-subjects designs since subjects have only
one score.
- Violating the assumption increases the Type I error rate, sometimes substantially.
- 0.049