Quick Question
Plot the tree that we created using cross-validation. How many splits does it have?
Explanation
If you follow the R commands from the previous video, you can plot the tree with prp(StevensTreeCV).
The tree with the best accuracy only has one split! When we were picking different minbucket parameters before, it seemed like this tree was probably not doing a good job of fitting the data. However, this tree with one split gives us the best out-of-sample accuracy. This reminds us that sometimes the simplest models are the best!