Message-ID: <loom.20090128T092130-467@post.gmane.org>
Date: 2009-01-28T09:27:08Z
From: Dieter Menne
Subject: Please Help for Augmented Prediction Plot
Chun-Hao Tu <tch28 <at> hotmail.com> writes:
> Hi R users,I have a question about augmented prediction plot (?augPred).
> The covariate of my data set is c(0, 0.01, 0.1, 1, 10, 100, 1000) and I
> have fitted a nonlinear mixed effects model. I use
> plot(augPred(out.nlme....)) to get the augmented prediction plot. However,
> because the scale of the covariate is too large thus I am not able to see
> the detail difference at c(0,0.01, 0.1, and 1). Could anyone
> tell me how to enlarge the plot at that range "c(0,0.01, 0.1, and 1)" ?
Very, very likely, if you have such a large range (frequently a drug dose),
you should think of doing a (shifted log?) transform of your data initially.
Try to do a residual plot plot(result(nlme)) might work first to check for
this. Maybe even plotting (0.001,0.01,...) would be more useful.
Otherwise, you could always use pred() manually and do a trellis plot
with some (log+x) transformed data.
Dieter