Hello,
I'm using S+ (2000 on windows and version 5.0 on unix) to make
classification trees for predictive modeling. One dataset I'm using
contains a factor predictor variable with 31 levels (used to classify a
factor variable with 9 levels). I read in the Splus manual (for
windows, S+ 2000) that the maximum allowed levels for
predictor variables is 32 and for response variables it is 128 levels. My
dataset is within those limits, but in both the windows and unix
platforms, the process "hangs" (for days). When I exclude this 31 level
variable, the process runs fine.
Additionally, I've used this 31 level predictor variable successfully in a
classification tree with a 2 level response variable.
My question is: are the computational problems a result of the combination
of using 31 levels to help classify 9 levels, or is it something
additional or beyond that?
Thank you for your help,
Jennifer
J e n n i f e r M i l l e r
Geography Department
San Diego State University
San Diego, CA 92182-4493
jmiller@rohan.sdsu.edu
http://www.rohan.sdsu.edu/~jmiller
|