Hello all, I'm making a decision tree with the rpart package. I want to prune the tree and in many tutorials it says to use cptable. Like so: opt <- which.min(model_rpart$cptable[, "xerror"]) The problem is that when I look up model_rpart$cptable it only show the columns CP, nsplit, rel error. So xerror and xstd are missing. How can this be? Model looks like this: model <- rpart(Product~. , data=trainData, control=rpart.control(minsplit=50, cp=0.002, xval=0)) Thank you. Kim
xerror and xstd are missing from cptable of the Rpart package
2 messages · Kim C., Adams, Jean
Kim, The "x" in "xerror" and "xstd" stands for cross validation. But you have specified no cross validations, xval=0. Try: model <- rpart(Product ~ ., data=trainData, control=rpart.control(minsplit=50, cp=0.002)) model$cptable Jean
On Tue, Feb 3, 2015 at 7:09 AM, Kim C. <minorthreatx at hotmail.com> wrote:
Hello all,
I'm making a decision tree with the rpart package. I want to prune the
tree and in many tutorials it says to use cptable. Like so: opt <-
which.min(model_rpart$cptable[, "xerror"])
The problem is that when I look up model_rpart$cptable it only show the
columns CP, nsplit, rel error. So xerror and xstd are missing. How can this
be?
Model looks like this: model <- rpart(Product~. , data=trainData,
control=rpart.control(minsplit=50, cp=0.002, xval=0))
Thank you.
Kim
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