Hello experts!
I have a design in which I have 4 levels of a treatment: 1, 2, 3, and 4. I predict that signal should be a monotonically increasing function with 1 having the lowest signal and 4 having the greatest. What is the best way to set up my EV files to test this?
In the past, I have tried 1 EV per treatment level, and then used a contrast of :
level 1 level 2 level 3 level 4
-3 -1 1 3
But this method seems to not be quite sensitive enough to detect the effect. Any other suggestions?
Thank you in advance for your help!
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