COMPLEX MIXED DESIGN: TWO BETWEEN-SUBJECTS FACTORS AND ONE WITHIN-SUBJECTS FACTOR

Abstract

COMBINING BETWEEN- AND WITHIN-SUBJECTS FACTORS As discussed in Chapter 13, a mixed design is one that contains at least one between-subjects independent variable and at least one within-subjects independent variable. Simple mixed designs have only two independent variables and so, by definition, must have one of each type of variable. Complex mixed designs contain at least three independent variables. The three-way complex mixed designs presented in this chapter and in Chapter 15 must (by definition) have two of one type and one of the other type of factor. In this chapter, we will focus on the design with two between-subjects factors and one within-subjects factor; Chapter 15 will present the design with one between-subjects factor and two within-subjects factors. A NUMERICAL EXAMPLE OF A COMPLEX MIXED DESIGN College students who signed up for a research study read vignettes in which their romantic partner was described as being attracted to another person; this attraction was depicted as being either emotional attraction with no physical component or physical attraction with no emotional component. Because this type-of-attraction variable was intended to be a within-subjects variable, students read both vignettes. After reading each vignette, the students completed a short inventory evaluating their feelings of jealousy; the response to this inventory served as the dependent variable. For the purposes of this hypothetical example, assume that no effects concerning the order of reading these vignettes was obtained; thus, we will present the results without considering the vignette ordering factor.