On Wed, 2004-07-07 at 07:57, Doran, Harold wrote: > Dear List: > > I have searched the archives and my R books and cannot find a method to > transform a continuous variable into a binary variable. For example, I > have test score data along a continuous scale. I want to create a new > variable in my dataset that is 1=above a cutpoint (or passed the test) > and 0=otherwise.
> My instinct tells me that this will require a combination of the > transform command along with a conditional selection. Any help is much > appreciated. Example: > a <- rnorm(20) > b <- ifelse(a < 0, 0, 1) > a [1] -1.0735800 -0.6788456 1.9979801 -0.4026760 0.1781791 -1.1540434 [7] -1.0842728 1.6042602 -0.7950492 -0.1194323 0.4450296 1.9269333 [13] -0.4456181 -0.8374677 -1.1898772 1.7353067 1.8619422 -0.1679996 [19] -0.2656138 -1.5529884 > b [1] 0 0 1 0 1 0 0 1 0 0 1 1 0 0 0 1 1 0 0 0 HTH, Marc Schwartz ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
