[R] Problem with Trellis graphics in nlme

[anthony staines]

Hi,
I would be grateful for help with a problem which is irritating me.
I am quite sure that I am doing something stupid, but I can't see what it 
is.

I am running R 1.7 on Windows 2000. The graphics device is the PC screen.

The graphics from the nlme demonstration in Bates an Pinheiro's manual work 
just as advertised. The CO2 data and the Orthodont data dsiplay 
beautifully.(plot(Orthodont, outer=true, key=false)  However. when I try to 
analyse a data set of my own, of about 2,770 measurements on 293 women the 
graphics go very peculiar. The graphics in the example from the manual fill 
most of the vertical extent of the graphics device. My graphics are correct 
horizontally, but are confined to about one-fifth of the vertical extent of 
the graphics device. As a result they look odd, and are almost usless for 
analysis. They do seem, however, to be the correct graphics (In this case 
maternal weight against gestational age for two groups of women).

I have read the manual for the lattice commands, and the nlme command, and 
indeed for the plain plot command, but failed to get any ideas. Roughly, I 
need to tell lattice to use the full vertical extent of the display device. 
If it helps, I can e-mail the offending images to you individually on 
request.

Anthony Staines,
Public Health,
UCD