[R-sig-ME] random regression with MCMCglmm

[Celine Teplitsky]

Dear all,

I would like to fit a random regression using MCMCglmm. The problem is I 
don't manage to include heterogeneous residual variance (when I use just 
one residual variance the model is running). I have created a factor 
(Cat) grouping the environments into 4 food qualities from good to bad, 
so the model looks like:
priorA<-list(G=list(G1=list(V=diag(2), n=2)),R=list(V=diag(4), n= 2))

MCMCglmm(LD ~ Age+stFood , random=~us(1+st2Food):ID, rcov = 
~us(Cat):units, data=Data,prior=priorA, family = 
c("gaussian"),nitt=120000, burnin=20000, thin=100)

but I get this error message, and I really don't know how to fix the 
problem:

Error in `[.data.frame`(data, , components[[1]]) :
   undefined columns selected

Many thanks in advance for any help

Celine

-- 

Celine Teplitsky
Département Ecologie et Gestion de la Biodiversité UMR 7204
Unité Conservation des Espèces, Restauration et Suivi des Populations
Case Postale 51
55 rue Buffon 75005 Paris

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