[R] Within-subject factors in lme: complemented

[lorenz.gygax at art.admin.ch]

The internet address to complement this is:
http://wiki.r-project.org/rwiki/doku.php?id=guides:lmer-tests

sorry for the double posting!

> -----Original Message-----
> From: Gygax Lorenz ART 
> Sent: Tuesday, January 16, 2007 7:32 AM
> To: r-help at stat.math.ethz.ch
> Subject: RE: [R] Within-subject factors in lme
> 
> 
> > Thanks for your suggestion. I guess the model you are fitting here
> > has only a single random effect term, namely subject. If the effect
> > of A depends on S, one needs to include an additional random effects
> > term for the S:A interaction.
> 
> It is not quite clear what you are after, but the 'if' sounds 
> as you would like to include interactions between your fixed 
> and random effects? This is done in the following way:
> 
> lme (y ~ A + B, random= ~ A | S )
> or
> lme (y ~ A + B, random= ~ B | S )
> or
> lme (y ~ A + B, random= ~ A + B | S )
> 
> with redard to discussions on degrees of freedom (and thus 
> testing in mixed-effects models) you may also want to refer to:
> 
> I hope this helps.
> Regards, Lorenz Gygax
> - 
> Swiss Federal Veterinary Office
> Centre for proper housing of ruminants and pigs
> Agroscope Reckenholz-Tänikon Research Station ART
>