"Is there a way to tell it to make a tree with only one node?" - see the maxdepth parameter in ?rpart.control
"Is it safe to assume that the cut-off value on the primary node is the ideal cut-off?" - trees are built sequentially; the first split will be the same for a tree with only one split or one that continues further. Terry T. ______________________________________________ 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.
