Decision tree construction a decision tree is grown in a recursive fashion by partitioning the training records into successively purer subsets We suppose Un is the set of training records that are associated with node n C=CL C2,.,CK) is the set of class labels 1/30/2021 PATTERN RECOGNITIONDecision tree construction A decision tree is grown in a recursive fashion by partitioning the training records into successively purer subsets. We suppose ◦ Un is the set of training records that are associated with node n. ◦ C={c1 , c2 ,…, cK} is the set of class labels. 1/30/2021 PATTERN RECOGNITION 7