AUC means "Area Under the Curve" and is a common summary statistic for repeated measures experiments (e.g. repeated measurements of serum concentration of a drug in an individual)in PK/PD studies (pharmacokinetic/pharmacodynamic).
I think the poster may actually mean "nonlinear regression for logistic models" rather than "logistic regression," which, of course, has a different statistical meaning. Hence nonlinear regression modeling for repeated measures is probably the issue here, for which nlme() is appropriate, I think. Alternatively, and perhaps somewhat less statistically desirable (though perhaps fairly standard in PK/PD modeling), one can use nls() or perhaps nlsList() to fit each individual's curve and compute the AUC's. So in any case, the answer appears to be "yes, you can use R" perhaps with add-ons to do what you want. -- Bert Gunter Genentech Non-Clinical Statistics South San Francisco, CA "The business of the statistician is to catalyze the scientific learning process." - George E. P. Box > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Spencer Graves > Sent: Wednesday, December 15, 2004 11:07 AM > To: [EMAIL PROTECTED] > Cc: [EMAIL PROTECTED] > Subject: Re: [R] AUC for logistic regression [was: (no subject)] > > What's AUC? If you mean AIC (Akaike Information > Criterion), and > if you fit logistic regression using "glm", the help file > says that glm > returns an object of class "glm", which is a list containing > among other > things an attribute aic. For example, suppose you fit a > model as follows: > > fit <- glm(y~x, famil=binomial()...) > > Then fit$aic returns the AIC. > > You may also wish to consider anova and anova.glm. > > hope this helps. spencer graves > > [EMAIL PROTECTED] wrote: > > >Dear R-helper, > > > >I would like to compare the AUC of two logistic regression > models (same > >population). Is it possible with R ? > > > >Thank you > > > >Roman Rouzier > > [[alternative HTML version deleted]] > > > >______________________________________________ > >[EMAIL PROTECTED] mailing list > >https://stat.ethz.ch/mailman/listinfo/r-help > >PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > > > > > > -- > Spencer Graves, PhD, Senior Development Engineer > O: (408)938-4420; mobile: (408)655-4567 > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
