Message-ID: <JLEPLGAANFCEAEDCAGJNEEPICEAA.dieter.menne@menne-biomed.de>
Date: 2003-04-29T14:50:41Z
From: Dieter Menne
Subject: Estimates with lme(...varPower())
Dear Douglas Bates,
> It would be more common to use the predicted response rather than the
> observed response for the varPower weights, as in
> varPower(form = ~fitted(.))
Following the example on page 223 of PB, I had used that first, but did not
achieve convergence. Will try with more iterations.
> If you use the observed responses then abnormally low observed
> responses will have unusually high weights in the fit, leading to low
> predictions, as you observed.
Dieter Menne