26-10-2010, 01:24 PM
cpt72.ppt (Size: 186 KB / Downloads: 143)
Decision Trees
Basics of Decision Trees
A flow-chart-like hierarchical tree structure
Often restricted to a binary structure
Root: represents the entire dataset
A node without children is called a leaf node. Otherwise is called an internal node.
Internal nodes: denote a test on an attribute
Branch (split): represents an outcome of the test
Univariate split (based on a single attribute)
Multivariate split
Leaf nodes: represent class labels or class distribution
Most decision tree generation consists of two phases
Tree construction
Tree pruning