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Swayam Prabha

Course Title

Multivariate Data Mining- Methods and Applications

Lecture 34

Training and Pruning Decision Trees

By

Anoop Chaturvedi

Department of Statistics, University of Allahabad

Prayagraj (India)

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Slides can be downloaded from https://sites.google.com/view/anoopchaturvedi/swayam-prabha

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Pruning the Tree ⇒ Control overfitting

Remove leaves and assign the majority label of the parent to all items.

Pre-pruning ⇒ Stop growing the tree at some point there is insufficient data to make reliable decisions.

Post-pruning ⇒ Grow the full decision tree and remove nodes for which we have insufficient evidence.

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