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Decision Tree Scalability Methods

 The scalable decision tree induction methods are RainForest and BOAT.

RainForest method maintains an AVC set for each attribute at each node. AVC stands for Attribute Value Classlabel.

BOAT, stands for Bootstrapped Optimistic Algorithm for Tree construction, uses a statistical technique known as bootstrapping., by which several smaller subsets are created. The several trees are created using the subsets and finally the full tree is generated using the trees created by smaller subsets.

BOAT was found to be two to three times faster than RainForest.

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