Re: [R] R: How to prune using holdout data

Let me give an outline of how to answer Alfredo's question via an example. I will split the data set "lung" into two peices. For these subjects with advanced lung cancer the physician's assessment of ECOG performance status (ph.ecog) is one of the most powerful indicators of outcome. Try to pred

[R] R: How to prune using holdout data

Thank you, Terry, for your answer. I'll try to explain better my question. When you create a classification or regression tree you first grow a tree based on a splitting criteria: this usually results in a large tree that provides a good fit to the training data. The problem with this tree is its