[R] Disentagling formulas

[Rebecca Sela]

I am writing a program in which I would like to take in a formula, change the response (Y) variable into something else, and then pass the formula, with the new Y variable to another function.  That is, I am starting with 
         formula <- Y~X1+X2+X3
and I'd like to do something like
         Y <- formula$Y
         newY <- f(Y)
         lm(newY~X1+X2+X3)
So far, it seems that my only option will be a very complicated sequence of steps involving match.call().  Is there a simpler way to change the response variable in a formula?

Thanks in advance!

Rebecca

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Rebecca Sela
Statistics Department
Stern School of Business
New York University