Statistics of Behavioral Sciences Practice Test

Repeated measures ANOVA is used when the same participants are tested under multiple conditions, a within-subjects design. This setup lets each person serve as their own control, reducing variability from individual differences and increasing the power to detect effects of the conditions. The key idea is that the independent variable is experienced by the same participants across multiple levels. If the dependent variable were nominal, ANOVA wouldn’t be appropriate because the outcome needs to be measured on at least an interval scale. Simply having two levels doesn’t require repeated measures—you could use a paired t-test for two levels. And a very large sample isn’t a must for this method; it can work with smaller samples, though power depends on effect size and variability.