In correlational analyses that involve more than one independent variable, the assumption of additivity means that
A) all the independent variables have linear relationships with the dependent variable.
B) the sum of the correlations between the independent variables and dependent variables equals 1.
C) all the independent variables have the same type of relationship (positive or negative) with the dependent variable.
D) there are no interactions between any of the independent variables.

Question

Quizplus · Accepted Answer

The assumption of additivity means that there are no interactions between any of the independent variables. This allows for the calculation of unique contributions of each independent variable to the dependent variable, as opposed to having their effects confounded or amplified by interactions with each other. The other choices (A, B, and C) are not necessarily true or relevant to the assumption of additivity.

In Correlational Analyses That Involve More Than One Independent Variable