Thank you. This is what I want. I need to study about attr :). Soyeon
On Fri, Feb 4, 2011 at 11:07 AM, David Winsemius <dwinsem...@comcast.net> wrote: > > On Feb 4, 2011, at 11:56 AM, Soyeon Kim wrote: > >> Dear All, >> >> I used glm and then used step function for stepwise regression. >> Now, I want to store the variables used in the stepwise regression. > > I am not sure that what you ask here is actually what you eventually ask and > will limit my answer to only what you ask below. > >> >> The code is the following. >> >> m_logistic <- glm(y ~ . + M1:T + M2:T + M3:T+ M4:T +M5:T, >> family=binomial("logit"), data = data) >> step_glm <- step(m_logistic) >> >>> step_glm$terms >> >> y ~ M1 + T + M1:T >> attr(,"variables") >> list(y, M1, T) >> attr(,"factors") >> M1 T M1:T >> y 0 0 0 >> M1 1 0 1 >> T 0 1 1 >> attr(,"term.labels") >> [1] "M1" "T" "M1:T" >> attr(,"order") >> [1] 1 1 2 >> attr(,"intercept") >> [1] 1 >> attr(,"response") >> [1] 1 >> attr(,".Environment") >> <environment: R_GlobalEnv> >> attr(,"predvars") >> list(y, M1, T) >> attr(,"dataClasses") >> y M1 T >> "numeric" "numeric" "numeric" >> >> How can I extract only "term.labels" ? >> > > Have you tried what would seem to be the obvious answer (assuming that is a > faithful console output): > > attr(step_glm$terms, "term.labels") > > ?attr > ?attributes > > (And the usual caveats: stepwise methods are often invalid.) > > -- > David Winsemius, MD > West Hartford, CT > > ______________________________________________ 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.