help > RE: Contrast help
Sep 9, 2019  05:09 PM | Andrew Zalesky
RE: Contrast help
Hi Lynette,

No - this is not correct.

In your design matrix, you will need a column of all ones, a column for group (1=patient, 0=control), a column for age and a column for the interaction between group and age. The last column is simply given by the multiplication of the age and group columns.

To test for an interaction between age and group, the contrast for a t-test is then [0 0 1] or [0 0 -1].

Andrew

Originally posted by lynette looi:
Dear Dr.Zalesky,

I wanted to check if I am using the correct contrasts:

I am interested in if there are more functional connectivity found in a control group as compared to a patient group, while adding age as covariates:

So I have used the following contrasts of [1 0 0] using a T-test?The first being control, second being patient and last being age.

Thank you so much.

Kind regards,
Lynette

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TitleAuthorDate
lynette looi Sep 9, 2019
RE: Contrast help
Andrew Zalesky Sep 9, 2019
lynette looi Sep 10, 2019
Andrew Zalesky Sep 10, 2019
lynette looi Sep 12, 2019
Andrew Zalesky Sep 12, 2019