Machine Learning

Chapter 3

Rule-Based Classifiers

3.1 Introduction to Rule-Based Classifiers

Rule-based classifiers use a set of IF-THEN rules for classification. We can express a rule in the following form:

IF condition THEN decision
Let us consider a rule R,
R: IF (humidity = “high”) and (outlook = “sunny”)
THEN play = “no”

Following are some terminologies that are used to describe the different aspects of the IF-THEN rules.

1. The IF part of the rule is called rule antecedent. In Rule R, it is (humidity = “high”) and (outlook = “sunny”).

2. The THEN part of the rule is called rule consequent. In Rule R, it is play = “no.”

3. The rule antecedent consists of one or more attribute tests combined together with the logical AND operator.

4. The rule consequent consists ...