Biomedical Engineering Reference
In-Depth Information
Leaf Node:
A node not further split, the termi-
nal grouping, in a classification or decision tree.
sis,
Working document
, Available at: http://www.
umist.ac.uk/csc/people/wolkenhauer.htm.
Linguistic Term:
One of a set of linguistic
terms, which are subjective categories for a lin-
guistic variable, each described by a membership
function.
kEy TERMS
Condition Attribute:
An attribute that de-
scribes an object. Within a decision tree it is part
of a non-leaf node, so performs as an antecedent
in the decision rules used for the final classifica-
tion of an object.
Linguistic Variable:
A variable made up of a
number of words (linguistic terms) with associated
degrees of membership.
Path:
A path down the tree from root node
to leaf node, also termed a branch.
Decision Attribute:
An attribute that char-
acterises an object. Within a decision tree is part
of a leaf node, so performs as a consequent, in
the decision rules, from the paths down the tree
to the leaf node.
Membership Function:
A function that
quantifies the grade of membership of a variable
to a linguistic term.
Node:
A junction point down a path in a deci-
sion tree that describes a condition in an if-then
decision rule. From a node, the current path may
separate into two or more paths.
Decision Tree:
A tree-like structure for repre-
senting a collection of hierarchical decision rules
that lead to a class or value, starting from a root
node ending in a series of leaf nodes.
Root Node:
The node at the tope of a decision
tree, from which all paths originate and lead to
a leaf node.
Induction:
A technique that infers gener-
alizations from the information in the data.