Chapter 8: Module 15 Flashcards
Differences between within-subject design (one-way and between subject design - two way)
within-subjects designs—in fact, all correlated-groups designs—are more powerful than between-subjects designs. Therefore, one reason for this choice would be to increase statistical power. In addition, the within-subjects design uses fewer participants and provides almost perfect control across conditions. Because the same people participate in each condition, we know that the individuals in each condi- tion are completely equivalent to each other and that the only difference between conditions will be the type of rehearsal used.
What is a one-way repeated measures anova?
An inferential statistical test for comparing the means of three or more groups using a correlated-groups design.
Assumptions of the one-way ANOVA?
- The data are on an interval-ratio scale.
- The underlying distribution is normally distributed.
3.The variances among the populations being compared are homogeneous. - The groups are correlated (within-subjects or matched-subjects)
HO and HA for a one-way repeated anova?
HO: The independent variable had no effect—the samples all represent the same population
HA: The independent variable had an effect—at least one of the samples represents a different population than the others
CRITICAL THINKING MODULE 15: Question 1:
The independent variable had an effect—at least one of the samples represents a different population than the others
A repeated measures ANOVA is statistically more powerful because the within-groups variance is divided into two sources of variance—that due to individual differences (subject) and that left over (error). Only the error variance is used to calculate the F-ratio. We therefore divide by a smaller number, thus resulting in a larger F-ratio and a greater chance that it will be significant.
CRITICAL THINKING MODULE 15: Question 2-
Identify other advantage(s) associated with using a within-subjects design:
