To classify a new instance, we start at the root and traverse the tree to reach
a leaf; at an internal node we evaluate the predicate (or function) on the data
instance, to find which child to go to. The process continues until we reach a leaf
node. For example, if the degree level of a person is masters, and the person’s
income is 40K, starting from the root we follow the edge labeled “masters,” and
from there the edge labeled “25K to 75K,” to reach a leaf. The class at the leaf is
“good,” so we predict that the credit risk of that person is good.