Fabio Berzaghi <fabe <at> dmu.dk> writes: > > hello all, > > I have a simple linear model with 4/5 variables that I am trying to fit. > I would like to find the lowest AIC value with any combination of all > the variables. I would like to implement this with a while/for loop. > Possibly I would like to generalize this so then I can use it when I > have many more variables. I do not want to use step AIC. At the moment I > am doing it manually but I would like to automate the process because I > have many species. I want to compute all possible combinations with all > the variables and know which combination gives the lowest AIC. > My function looks like this >
[snip] You should really use a data argument, i.e. lm(tl~poly(bs0011yme,2)+poly(bt0011yme,2)+poly(ss0011sme,2)+ poly(st0011sme,2),data=subxy) (It won't change the answers but it will make everything work better if you want to post-process the fit, e.g updating or predicting) > I cannot seem to find a library that has a function that does this > automatically. Check out the MuMIn, AICcmodavg, and glmulti packages. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.