Date: Mon, 9 Mar 2009 16:50:39 -0400
Reply-To: Marianne Kang <tongjunkang@HOTMAIL.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: Marianne Kang <tongjunkang@HOTMAIL.COM>
Subject: Re: use glimmix to test if the variance is significant for random
Thanks for your replying.
1. I think the reason I want to see if the random effect is significant
is: should I conclude zipcode as a random varialbe or fixed variable. If
the random effect is not significant, why should we bother to have it
2. I performed the moran's I test and hot-spot analysis, both showed the
distribution of event (late hiv testing cases) has clustering pattern.
That is the reason why I include zipcode as a random variable.
3. If I run model with zipcode as random variable in proc glimmix, then
run again with zipcode as a fixed variable, and the beta coefficients for
fixed variables in both model changed a lot, let's say, more than 20%, can
I say the random effect should be included in the model?