-----Original Message-----
From: r-sig-mixed-models-bounces at r-project.org
[mailto:r-sig-mixed-models-bounces at r-project.org] On Behalf
Of Andrew Robinson
Sent: Friday, June 27, 2008 10:18 PM
To: Maria Eva Gongora
Cc: r-sig-mixed-models at r-project.org
Subject: Re: [R-sig-ME] help random effects unested
Hi Maria,
it sounds like you would like those factors to be crossed.
It is possible to cross factors within lme but it is not easy
- you might find some guidelines searching R-help via Google.
Alternatively you could try to use the lmer() function
within the lme4 package, this function allows you to cross
random effects.
I hope that this helps,
Andrew
On Sat, June 28, 2008 2:13 am, Maria Eva Gongora wrote:
I am using mixed effect models (library nlme, lme) to evaluate
factors that influence bycatch of hake in a shrimp fishery.
collected though an on-board observer program and I
the vessel id and the observer id as random effects. A
expect the observer effect to be independent of vessel.
did not find a way to incorporate both factors as independent,
unnested random effects; I could only estimate the effects
as "vessel" and "observer in vessel"
(nested).
Is it possible to incorporate two random effects unested?
Lic. Mar?a Eva G?ngora