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ID3
Name |
ID3 |
Description |
The algorithm ID3 (Quinlan) uses the method top-down induction of decision trees.
Given a set of classified examples a decision tree is induced, biased by the
information gain measure, which heuristically leads to small trees.
The examples are given in attribute-value representation.
The set of possible classes is finite.
Only tests, that split the set of instances of the underlying example languages
depending on the value of a single attribute are supported.
Depending on whether the attributes are nominal or numerical, the tests either
- have a successor for each possible attribute value, or
- split according to a comparison of
an attribute value to a constant, or depending on if an attribute value belongs to a
certain interval or not.
The algorithm starts with the complete set of examples, a set of possible tests and
the root node as the actual node.
As long as the examples propagated to a node do not all belong to the same class and
there are tests left,
- a test with highest information gain is chosen,
- the corresponding set of successors is created for the actual node,
- each example is propagated to the successor given by the chosen test,
- ID3 is called recursively for all successors.
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Specialization |
ID3 Software
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Generalization |
Top-Down Induction of Decision Trees (TDIDT)
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Example Languages |
Attribute-Value
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Method Type |
Algorithm
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Measures |
Information Gain
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