Hi all,

I am trying to model a polytomous logistic model using CATMOD. I have 3 categories for the outcome variables (1, 2 and 3). Those are ordonned values (Certain/Probable, possible, unrelated).

See for an example: http://www.id.unizh.ch/software/unix/statmath/sas/sasdoc/stat/chap22/sect41 .htm

Here is a simplified model I tried:

PROC CATMOD DATA=fiche_event4; RESPONSE 1 0.5 0; DIRECT nbpres; MODEL q2bis = nbpres / NOITER NOPROFILE CLPARM ; WHERE qpat0; RUN;

ERROR: The response functions are linearly dependent since the number of functions per population,1, is greater than or equal to the number of response levels, 1, in population2. 1611 QUIT;

It works when I do not specify the RESPONSE structure (so it create 2 fucntions). But I only want to have one. It stops. I don't understand the message. I did a search in the archives. It came up several times, without any answers.

Any idea or explanation?

Oups! I juste discovered that taking out nbpres (nb of prescriptions, continuous) solve the pb. I am gonna work on that, but feel free to help with any insight.

JP