[R] Mixed-effects models / heterogenous covariances

[David Duffy]

> Message: 24
> Date: Tue, 31 Jan 2006 18:22:52 +0000
> From: "Lutz Ph. Breitling" <lutz.breitling at gmail.com>
> Subject: [R] Mixed-effects models / heterogeneous covariances
> To: r-help at stat.math.ethz.ch
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> 	<2e38a1c80601311022i2e1be92doa60b80b50b69eb0c at mail.gmail.com>
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> Dear R-list,
>
> maybe someone can help me with the following mixed-effects models
> problem, as I am unable to figure it out with the 'nlme-bible'.
>
> I would like to fit (in R, obviously) a so-called animal model (google
> e. g. "Heritability and genetic constraints of life-history" by Pettay
> et al.) to estimate the variance component that is due to genetic
> effects. The covariances of the genetic random effects between
> observations are given by the different degrees of relatedness between
> the individuals examined. (I find it difficult to explain, but Pettay
> et al. describe it nicely in their methods section...)
>
> Is there any straight-forward way to fit such a model with R? I first
> thought I could handle it somehow with nlme's correlation structures,
> but these within-group structures are quite a different thing, right?
>
> Any suggestions would be highly appreciated-
> Lutz
>
> --
> Lutz Ph. Breitling
> University of Leeds/UK

lmekin and coxme in Terry Therneau's kinship package may help.

David Duffy.