Hello,
I'm trying to fit a linear mixed effects model of the form:

lme(y ~ x * Sex * Year, random=x|subject)

where Sex and Year are factors with two and three levels respectively. I 
want to compare the fixed effects for each level to the overall mean, but 
the default in R is to compare to the first level. This can be changed by 
adding the term -1 to the righthand side of the model formula. But what I 
can't figure out is how to do this for both factors simultaneously. If I 
specify the model as:

lme(y ~ x * Sex * Year-1, random=x|subject)

the output gives me the fixed effects for each level of "Sex" compared to 
the overall mean, but still only gives me the effects of the second two 
levels in the "Year" factor compared to the first level. How do I specify 
the fixed effects structure to allow comparisons to the overall mean for 
each level of both factors?

Many thanks,

Martin Biuw


Martin Biuw
SEA MAMMAL RESEARCH UNIT
Gatty Marine Laboratory
School of Environmental and Evolutionary Biology
University of St Andrews
Fife, Scotland KY16 8LB
UK
phone +44 (0)1334 462630
fax + 44 (0)1334 462632
http://www.smru.st-and.ac.uk
http://www.smru.st-and.ac.uk/research/individuals/martinbiuw.htm

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