--- Barth Riley <[email protected]> wrote:
> > > I am running a multilevel logistic model using gllamm. <snip>
> > > I get the following error message: "initial vector: matrix must
> > > be dimension 28" <snip> There are 28 terms in the initial set of
> > > coefficients, so why would I get this error message?
--- Maarten buis answered:
> > Does the set of dummies contain the reference category? <snip>
--- Barth Riley <[email protected]> wrote:
> Each dummy represents a category for each question. So do I need to
> leave out the reference category dummy for each question (e.g., leave
> out d1_0 from d1_0, d1_1, d1_2) or just one dummy variable?
One for each question: The dummies are stand-ins for a categorical
variable. In your case you have a categorical variable for each
question, so you have as many reference categories as there are
questions.
-- Maarten
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
___________________________________________________________
Support the World Aids Awareness campaign this month with Yahoo! For Good http://uk.promotions.yahoo.com/forgood/
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
