Memory and Choosing the Type of ANOVA: In a fictional study, a cognitive psychol
ID: 3306405 • Letter: M
Question
Memory and Choosing the Type of ANOVA:
In a fictional study, a cognitive psychologist studied memory. The researcher randomly assigned 120 participants to one of three conditions: (1) group members introduced themselves once, (2) group members were introduced by the experimenter and by themselves, and (3) group members were introduced by the experimenter and themselves and also wore nametags throughout the group activity.
A.) How could this researcher redesign this study so it would be analyzed with a two way between groups ANOVA? Be specific.
B.)How could the researcher redesign this study so it would be analyzed with a two way ,mixed design ANOVA? Be specific.
Explanation / Answer
A)
We use the two-way ANOVA when we have two Independent Variables(IV) and the IVs both have two or more levels. IVs are both between-subjects in Nature.
In our case the IV could be:
IV1:Randomly divide them in 1 of 3 conditions as done earlier
IV2:Randomly divide them in two groups and give coffee to one group and tea to other.
(Note: This method can also be used for a cross-study for checking dependency of two or more articles)
This information would allow us to place people into one of the "cells" or conditions. This is a Two-way Factorial Design.There are two IVs, each person is placed in only one cell, and each level of one IV is "crossed" with each level of the other IV. Crossed meaning that given our levels of the two IVs, we have all possible combinations of levels. Specifically, this is a 3 X 2 Factorial Design – 3 levels of IV1 and 2 levels of IV2. Therefore we will have 3 X 2 = 6 Groups.
B)
A Two-way mixed ANOVA is often used in studies where you have measured a dependent variable over two or more time points. Suppose if the researcher wants to know if the people have 'Low','Medium' or 'High' cognition depending on their 'Education level' than this gives rise to different factors of "between-subjects" and "within-subjects". When all subjects have undergone two or more conditions (i.e., where "cognition" and "education" are your "within-subjects" factor) but also when your subjects have been assigned into two or more separate groups(i.e., where subjects are divided into one of three conditions as is mentioned in question) these groups form your "between-subjects" factor. The primary purpose of a mixed ANOVA is to understand if there is an interaction between these two factors on the dependent variable.