[R] help for bootstrap of backward stepwise logistic regression

[Giuseppe Biondi Zoccai]

I would like to perform a bootstrap validation of a backward stepwise
logistic regression analysis, but I am a beginner with R and I am not
sure of how to do it.
Is there anyone that can send me a sample file in tab format (that I
can modify in Excel by pasting my data) and the pertinent R algorithm?
Many thanks
Giuseppe 

-- 

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Dr. Giuseppe Biondi Zoccai
Interventional Cardiology Unit
St Raffaele Hospital
via Olgettina 60
20132 Milan ITALY
Phone: +39-3408626829
Fax: +39-0226437339
Email: gbiondizoccai at gmail.com

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^