Re: ASReml-R and using weights with the ped() function

kiwi wrote:
> I've not received any comments about this one yet. There's a further
> development:
>
> I mentioned the 'singularity' error I got when I ran this:
> Code:
> > discard.asr <- asreml(fixed = Discard_Total ~ 1 + Season,
> random = ~ped(Vine, var = T) + Block,
> data = model.df, na.method.X = "include",
> ginverse = list(Vine = G.inv$ginv))
> However, it didn't prevent convergence.
> I mentioned that adding a weights argument causes an error to do with a
> Code:
> Error : Abnormal termination
> Singularity in Average Information Matrix
> result.
>
> At that time, I considered it possible that the singularity had a
> cabability of creating a problem with weighting, but otherwise it was
> benign.
>
> I've found an instance where even without a singularity problem, it's
> still a problem. The first one works fine; the second falls over:
> Code:
> resp.asreml <- try(asreml(fixed = form,
> random = ~ped(Vine, var = T) + Block,
> data = model.df, na.method.X = "include",
> ginverse = list(Vine = G.inv$ginv)))
>
> model.df$Wt <- rep(1, nrow(model.df))
>
> respW.asreml <- try(asreml(fixed = form,
> random = ~ped(Vine, var = T) + Block,
> weights = Wt,
> data = model.df, na.method.X = "include",
> ginverse = list(Vine = G.inv$ginv)))
> The 'singularity' problem returns even though it would appear to the
> ignorant that the same model was being tried.
>
> That leads me to conclude that it can't just be me.
> So my question is this:
> Has anyone ever got weights to work when using the ped() function?
>
>
>
>
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>
While you provide no data or output, you probably are lacking a suitable
pedigree structure for your model and that there are terms confounded.
Please check your data and pedigree file and then check your model as
some terms can not be fitted as indicated. In particular:
1) Check that the model runs without including the pedigree.
2) If it does, run the model with only pedigree and the intercept.
3) If that model works slowing increase the model complexity with
additional fixed and random effects

Bruce
Received on Fri Dec 10 2008 - 08:14:29 EST