Hello everyone,
I am having troubles regarding an analysis I want to do. I have a relative simple experiment with 4 conditions. Now, reaction times are different depending on conditions. I tried to account for that through modeling EV duration from onset 'til time of reaction. Now I would like to add the average response time per condition as a regressor in the model but I am unsure as to how to accomplish that. I tried to add 4 regressors on higher level that included the demeaned average response time per condition per person (demeaning done per person by subtracting mean from mean of condition) but I got the error message, that one or more EVs are close to a linear combination of the others. Now I am unsure as to how to incorporate the mean reaction time per condition.
Thanks for your help,
Susanne Sommer
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