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models with fixed effets nested in random effects

Hi Wayne,

your question points to a broader problem with the specification of
fixed and random effects.  It is often true that fixed effects are
aliased with elements of the underlying experimental design - such as
in split plot designs - and then it makes sense to declare the effect
as both fixed and random.  (Actually I think that it makes more sense
to create a new variable identical to the first and use one for fixed
and the other for random, but that is neither here nor there.)  I'm
not sure whether this is true in your case.

Anyway, I'm confused that you write "The treatment was applied:
Location/Subsite/TREATMENT/year" and then in your model statement you
have only three levels: FenceEnd/FEsection/MIT_UNMIT. Also, it seems
that two treatment effects appear in the random statement.  I can't
reconcile that with your earlier description.  Can you try to clarify
these - perhaps by giving a more complete description of the design?

Cheers,

Andrew
On Fri, Mar 02, 2007 at 11:44:01AM -0700, Hallstrom, Wayne (Calgary) wrote: