Multinomial response variable and random factors in GLIMMIX procedure

deleted_user — Thu, 13 Aug 2009 15:02:23 GMT

Hello,

I have a multinomial ordered response variable (0, 1 and 2) corresponding to population trends (negative, no trend, increasing); 2 continuous independient variables (use and distance) and I am controlling by taxonomy, so I have as random variables family adn genera nested into family. My final model code is:

proc glimmix data=sasuser.Indices_octene ;
class trend family genera;
model trend = use distance distance*distance / dist=multinomial solution;
random family genera(family);
run;

I would like to know:
- Is this a logistic regression with random factors?
- Why can't I get the AIC of the model? (I get it if I delete random factors for the model)
- How could I know if my model is correct? do I have to look at the residuals, and how could I do it?
- Should I wonder about overdispersion? how could I get a measure of that?

Maybe too many questions. Thank you very much.

Grego.

Re: Multinomial response variable and random factors in GLIMMIX procedure

deleted_user — Thu, 13 Aug 2009 15:17:53 GMT

I also found that if I use a normal error distribution, the estimates are almost the same when using multinomial distribution, but with the oposite sign. How should I interpret the sign of the estimates in the model with multinomial error distribution?

Thanks.

topic Multinomial response variable and random factors in GLIMMIX procedure in Statistical Procedures

Multinomial response variable and random factors in GLIMMIX procedure

Re: Multinomial response variable and random factors in GLIMMIX procedure