Odds ratios from lrm plot

The Design package is obsolete.  Use its replacement rms - see
http://biostat.mc.vanderbilt.edu/Rrms.  Use something like the following to
reproduce what you already have:

To plot odds ratios against a specific value of x2 and at a specific x1,
type ?contrast.rms to see examples.
Frank

The code

library(Design)
f <- lrm(y~x1+x2+x1*x2, data=data)
plot(f)

produces a plot of log odds vs x2 with 0.95 confidence intervals. How do I
get a plot of odds ratios vs x2 instead?

Thanks

-----
Frank Harrell
Department of Biostatistics, Vanderbilt University
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The code

library(Design)
f <- lrm(y~x1+x2+x1*x2, data=data)
plot(f)

produces a plot of log odds vs x2 with 0.95 confidence intervals.  
How do I
get a plot of odds ratios vs x2 instead?

You would construct a dataset that had selected combinations of x1 and  
x2 and then plot the "response".

It's been a couple of years since I used Design. Harrell migrated to  
lattice plots when he upgraded to 'rms' and changed the Predict/plot  
interface a bit. In the new version it might  something like  
plot(predict(f, x1=seq( ...), x2=c(1,2), type= "fitted"), deopending  
on teh data arrangement.  Why don't you look more closely at the help  
page for `lrm` and work through the examples. At least in the current  
'rms' version there is more than one worked example, and I'm pretty  
sure there were one in Design before that.

David Winsemius, MD
West Hartford, CT