[R] Symbol size in plots

[Maurizio Pisati]

Dear R-listers,
what is the best way to draw an XY scatterplot with symbol size 
proportional to the value taken on by a third variable?
Thank you very much for any help,
Maurizio Pisati




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  Maurizio Pisati
  Assistant Professor
  Department of Sociology and Social Research
  University of Trento
  Via Verdi, 26
  38100 Trento TN
  Italy
  Tel: +39-461-881315
  Fax: +39-461-881348
  E-mail: maurizio.pisati at galactica.it
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