R help - Aug 2009 - how to specify between group variance in lme

Hello r-help,

I am using lme with two specs for the variance func

varComb(varFixed(~1/n)),varPower(~Age))

this produces worse forecasts than the lm model with simple

weights=n

I think due to the fact that the lme spec works on variance inside the group. I
need to show it that 1/n scales the variance between groups.

Is that possible?

I cannot disclose my dataset, but could post plots if that is possible somehow,
let me know. Anova shows that everything in random=~poly(age,2) is significant.

Thank you all very much.
Stephen

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Clarification:

Lm is much better than the base forecast from lme level=0,

Level=1 produces a much tighter fit than lm.

I was expecting that level=0 would produce something very close to lm, but it
does not.

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