Question

Difference between pre pruning and post pruning in decision tree

Answer 1

Answer:

Pruning means reducing size of the tree that are too larger and deeper. ... First is Post pruning, in which the tree is build first and then reduction of branches & levels of the decision tree is done. Second is Pre pruning, in which while building the decision tree keep on checking whether tree is overfitting.

Answer 2

Explanation:

Pre-pruning that stop growing the tree earlier, before it perfectly classifies the training set. Post-pruning that allows the tree to perfectly classify the training set, and then post prune the tree.