Unformatted text preview: umstance the more complex an analysis becomes the less power there is Kinds of Research Questions Kinds of Research Questions asked by MANOVA The questions are mostly the same as ANOVA just on the linearly combined DVs instead just one DV. Are there any main effects?
Are there any main effects? Holding all other effects constant, is a difference among groups greater than expected by chance? Are there any main effects?
Are there any main effects? Holding constant can mean:
– Controlling for other effects by averaging over them in a factorial design
– Holding extraneous variables constant or counterbalancing/randomizing their effects
– Using covariates to adjust the composite DV in order to create a state of “pseudo equality” Are there any main effects?
Are there any main effects? Tests of main effects are orthogonal if they are completely crossed and equal samples in each cell, they are only linked by a common error term Are there any interactions Are there any interactions among the IVs? Does change in the linearly combined DV for one IV depend on the levels of another IV?
For example: Given three types of treatment, does one treatment work better for men and another work better for women?
If equal samples in each cell then one interaction is independent of main effects and other interactions. Which DVs are most Which DVs are most important? If there are any significant main effects or interactions, on which individual DV is there the most change (difference), if any, “caused” by the levels of the IV?
You can follow a significant MANOVA with individual ANOVAs in order to see on which DV is there large, medium, small or no effect. Which DVs are most Which DVs are most important? Another procedure is t...
View Full Document
- Winter '14
- main eﬀects, MANOVA