Not estimable in the model [BE/BA News]

posted by ElMaestro  – Denmark, 2017-03-14 12:02 (3380 d 21:03 ago) – Posting: # 17152
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Hi The user,

❝ I decided to continue the topic (moreover Simon kindly directed me here).

❝ Regarding "Not estimable". Could you please share your expirience with following issue? When I use such a model: Sequence+Period+Treatment+Group+Patient(Sequence) I get "Not estimable" in the results of ABE in WNL. Model is wrong? When I delete the "group" than error dissapeares. Comments: it is BE cross over study in 3 groups and all effects are fixed.


Hmmmm... thinking loud here... In a type III model Group will have in your case up to three columns in the model matrix, but every column is equally represented by the subjects in the respective groups. Hence Group has zero df's and no effect for any level of Group can be estimated.

Try a type I model with Group before Subjects, then you'll get something that is estimable, I believe.

Pass or fail!
ElMaestro

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