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help > How to add covariates to paired sample t-test design?
Aug 10, 2022 05:08 PM | Miranda Ramirez
How to add covariates to paired sample t-test design?
Hello all
I have a within subjects design, and I want to examine a covariate of interest. Each subject had two maps generated (wins > control and nowins > control). These are my two con maps going into the second level as a paired t-test (wins>control > nowins>control). I want to see how learning rate (covariate of interest) scales with this comparison, but I'm confused on how to enter the covariate and what the contrast vector should be.
Should there be two vectors for the covariate values, one for the con_0001 and one for con_0002, or should they be in the same vector?
I only have one learning rate per subject, so should this learning rate value be duplicated (0.5 0.5 per subject) or with zeros separating (0.5 0 per subject)?
What should the contrast vector look like? My guess with how my design is currently set up, it would be .5 -.5 .5 -.5.
I attached a screenshot of the design matrix in case my description was not clear.
Thanks!
I have a within subjects design, and I want to examine a covariate of interest. Each subject had two maps generated (wins > control and nowins > control). These are my two con maps going into the second level as a paired t-test (wins>control > nowins>control). I want to see how learning rate (covariate of interest) scales with this comparison, but I'm confused on how to enter the covariate and what the contrast vector should be.
Should there be two vectors for the covariate values, one for the con_0001 and one for con_0002, or should they be in the same vector?
I only have one learning rate per subject, so should this learning rate value be duplicated (0.5 0.5 per subject) or with zeros separating (0.5 0 per subject)?
What should the contrast vector look like? My guess with how my design is currently set up, it would be .5 -.5 .5 -.5.
I attached a screenshot of the design matrix in case my description was not clear.
Thanks!