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unit 4/05_Rule_Based_Classification.md

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+# Rule-Based Classification
+
+**Rule-Based Classifiers** use a set of **IF-THEN** rules to classify data.
+
+## Structure
+- **Rule**: `IF (Condition) THEN (Class)`
+- *Example*:
+  - `IF (Age = Youth) AND (Student = Yes) THEN (Buys_Computer = Yes)`
+
+## Extracting Rules from Decision Trees
+- We can easily turn a decision tree into rules.
+- Each path from the **Root** to a **Leaf** becomes one rule.
+- The conditions along the path become the `IF` part (joined by AND).
+- The leaf node becomes the `THEN` part.
+
+## Advantages
+- Easy for humans to understand.
+- Can be created directly or from other models (like trees).