[R] proportional area venn diagrams?

[Michael Friendly]

In http://finzi.psych.upenn.edu/R/Rhelp02a/archive/14637.html

some rudimentary R functions were given  for drawing
proportional area venn diagrams with area of each intersection ~ the 
count in a 2 x 2 x 2 table.

I'm interested in this, for another application: showing the 
correlations among Y, X1, X2 using
area ~ r^2 of each pair (sometimes called a Ballantine diagram).

Before I attempt to hack the code given in that post, are there any 
packages/functions that do venn diagrams
with proportional areas?  Rseek turned up quite a view venn-like 
functions, but I couldn't find any
that drew them with proportional areas.

-Michael

-- 
Michael Friendly     Email: friendly AT yorku DOT ca
Professor, Psychology Dept.
York University      Voice: 416 736-5115 x66249 Fax: 416 736-5814
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