--- On Mon, 16/2/09, Michael Stobernack wrote:
> What do you mean by 'estimate 4 extra
> coefficients'? Do you mean 4
> extra values of the residual variance?
Yes, but the real point is that if you are
uncomfortable with a model containing all
the interactions then you should also be
uncomfortable with separate models for each
group.
-- 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 N515
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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