I have a completely within-subjects design with 3 independent variables:
- Trial type (3 levels)
- Task order (2 levels)
- Modality (3 levels)
However, for one of my levels of Trial type, the Task order and Modality levels are redundant (because it is essentially a baseline measurement).
Ideally, I'd like to run a 3 (trial type: 1, 2, or 3) x 2 (task order: a or b) x 3 (modality: vm, av, hm) repeated measures ANOVA.
Do you know of a way around this? If I were to duplicate the Task 3 data across 'modalities' and 'task orders' I would have the correct number of levels for each within-subjects factor (i.e. six identical columns of data to represent imaginary modalities and task orders for Task 3). I'm assuming this violates an assumption but I'd be worried about looking at a similar analysis with a huge number of paired sample t-tests. Is lots of t-tests the way to go? Thanks for your help!