topic Re: Proc GLIMMIX with 3 random intercepts - univariate analyses [how to improve your question] in Statistical Procedures

Proc GLIMMIX with 3 random intercepts - univariate analyses

KPCklebspn — Sun, 23 Dec 2018 23:05:42 GMT

Hi all,

I've got a hierarchical model with 3 random intercepts and some fixed effects.

I want to present the full model (3 random intercepts plus room- and unit-level factors fixed effects). Outcome is a dichotomous var.

If this were a simple logistic regression, we'd present the univariate analyses prior to presenting the full model.

How to univariate analyses work with multilevel modeling? When I'm doing the univariate analysis for each room- and unit-level factor, do I include all 3 random intercepts?

Thx!

Re: Proc GLIMMIX with 3 random intercepts - univariate analyses [how to improve your question]

Community_Guide — Fri, 28 Dec 2018 03:33:26 GMT

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Re: Proc GLIMMIX with 3 random intercepts - univariate analyses

Haris — Fri, 28 Dec 2018 18:27:10 GMT

Sounds like you need to report univariable effects of your FIXED factors while controlling for your random effects. Random effects usually reflect sampling differences that you want to control for rather than focus on.

It may also be interesting to know if the effects of your fixed variables are different across the levels of your random effects. If that is the case, random intercepts model may not be appropriate and you may need to model cross-level interactions.

The final answer is somewhat context-specific.