Re: [R] AIC function and Step function

Thank you, Kingsford. Then I am wondering if there are other ways to write R codes to calculate the "weights" ? Thanks! Dana Kingsford Jones wrote: > > On Sun, Nov 30, 2008 at 5:05 PM, Dana77 <[EMAIL PROTECTED]> wrote: >> >> Thanks for kind help from Steven and Christos last time. Now I

Re: [R] AIC function and Step function

On Sun, Nov 30, 2008 at 5:05 PM, Dana77 <[EMAIL PROTECTED]> wrote: > > Thanks for kind help from Steven and Christos last time. Now I got new > problem regarding the codes for calculating the "weights" (w) in "AIC () > function". > The original code is as below: > > getAnywhere("logLik.lm") > fu

Re: [R] AIC function and Step function

Thanks for kind help from Steven and Christos last time. Now I got new problem regarding the codes for calculating the "weights" (w) in "AIC () function". The original code is as below: > getAnywhere("logLik.lm") function (object, REML = FALSE, ...) { res <- object$residuals p <- ob

Re: [R] AIC function and Step function

Hi Dana, Many thanks to Christos Hatzis who sent me an offline response, pointing out the new functions that make this much easier than my last suggestions: methods() and getAnywhere() > methods("extractAIC") [1] extractAIC.aov* extractAIC.coxph* extractAIC.glm* extractAIC.lm* ext

Re: [R] AIC function and Step function

Hi Dana, Of course the only true way to know what the AIC calculations are is to read the source code. From within R, what with namespaces, that is becoming increasingly difficult. The AIC() function is not too hard to find from R. > AIC function (object, ..., k = 2) UseMethod("AIC") So now