I know if I have a dataframe with columns y, x1, x2 and I wish to have y as my y value and x1 and x2 as x values I can do: y ~ x1 + x2
or y ~. but can someone explain what . actually is or what its transposed into? I searched for this with no success, reading the "formula" manual pages. Brian ______________________________________________ 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.
