That still discards the other data columns. For example, in the data frame
V1 V2 V3 V4 1 1 1 NA 1 2 1 NA 1 1 3 1 NA 1 1 4 1 1 1 1 5 1 1 1 1 Suppose I was running a regression using V1 and V2. R will remove rows 2 and 3 due to the "NA." I would like a way to look at only the observations used for the regression, the data frame: V1 V2 V3 V4 1 1 1 NA 1 4 1 1 1 1 5 1 1 1 1 If I run na.omit(subset(dataframe, select= c(V1,V2)) it returns V1 V2 1 1 1 4 1 1 5 1 1 Sorry for being unclear the previous time. Justin On Tue, Sep 20, 2011 at 4:54 AM, David Winsemius <dwinsem...@comcast.net>wrote: > > On Sep 19, 2011, at 8:49 PM, justin jarvis wrote: > > I have a data set with many missing observations. When I run a >> regression, R of course discards the observations (the whole row) that >> have "NA". I want to tabulate some baseline characteristics (column >> means) but only for the observations that R used for the regression. >> I tried to recreate this data frame by using na.omit on the original >> data frame, but this will not work as this will discard an observation >> with an "NA" in any column, and not just in the covariates. >> >> In summary, I only want to remove observations that have an "NA" in >> the covariate columns. Something like Stata's e(sample), as far as I >> > > na.omit(subset(dfrm, select= <covariate-vector> ) # or equivalent > > can tell. >> >> Justin Jarvis >> PhD student, University of California, Irvine >> >> ______________________________**________________ >> R-help@r-project.org mailing list >> https://stat.ethz.ch/mailman/**listinfo/r-help<https://stat.ethz.ch/mailman/listinfo/r-help> >> PLEASE do read the posting guide http://www.R-project.org/** >> posting-guide.html <http://www.R-project.org/posting-guide.html> >> and provide commented, minimal, self-contained, reproducible code. >> > > David Winsemius, MD > West Hartford, CT > > [[alternative HTML version deleted]] ______________________________________________ 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.