Hello. Is there a way to test for equality of coefficients in multilevel models (using SAS 9.3 or 9.4)? I have some multilevel (random effects) models that I am estimating with PROC MIXED and I would like to know if two coefficients are statistically different from one another.
If this was not a multlevel I would have something like the equation below and use the test option,
y=X1B1+X2B2+X3B3+e
proc reg data=temp1;
model zwfl=x1 x2 controllist;
t1: test x1=x2;
Is there a way to do this in a multilevel context? So after the following code?
proc mixed data=temp1;
class nbhid;
model zwfl=x1 x2 controllist/solution;
random intercept/sub=nbhid;
I would also like to do this after running a PROC GLIMMIX (similar situation with dichotomous outcome).
Thank you!
To matche the PROC REG example of testing x1=x2
You would use a contrast statement that looks at x1-x2 to see if the result is not significantly different than zero.
Hey,
are the statements CONTRAST and ESTIMATE what you are looking for?
Bye,
Daniel
I thought that might be it, but aren't those more for predicted probabilities and not for testing the difference between estimated coefficients/effects?
To matche the PROC REG example of testing x1=x2
You would use a contrast statement that looks at x1-x2 to see if the result is not significantly different than zero.
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