This paper concerns a decision-tree pruning method, a key issue in the deve
lopment of decision trees. We propose a new method that applies the classic
al optimization technique, dynamic programming, to a decision-tree pruning
procedure. We show that the proposed method generates a sequence of pruned
trees that are optimal with respect to tree size. The dynamic-programming-b
ased pruning (DPP) algorithm is then compared with cost-complexity pruning
(CCP) in an experimental study. The results of our study indicate that DPP
performs better than CCP in terms of classification accuracy.