[R] two y-axis using ggplot

[Thorsten Vogel]

Dear List Members

As a relatively new R user I am extremely glad for there being a nice 
tool such as ggplot for producing easily nice graphs in R. Now I want to 
produce graphs with two y-axis. I know that this has been asked a 
hundred times with respect to standard plots in R. (The answer, to my 
knowledge, has always been "No" or "No, see the help archive".) But: Is 
there a more straightforward way IN GGPLOT to draw several lines in one 
graphs using two different scales and displaying these two scales on the 
y-axis and the, say, z-axis? Seems to be an obvious extensions of 
typical plot commands but I can't find any suggestions how to do it.

Many thanks for any suggestions or hints.

Best,
Thorsten

--
Dr. Thorsten Vogel 
Institute for Economic Theory II
School of Business and Economics
Humboldt-Universität zu Berlin
Spandauer Str. 1
D-10178 Berlin
tel.: +49 (30) 2093 5667
fax: +49 (30) 2093 5696