Decision Trees

• One really simple algorithm for categorising is a decision tree.
• Here I have one of the simplest trees.
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• You start at the root, and ask the question. Here the question is binary, but there can be multiple branches.
• Depending on the answer, you move to the next node (or to a leaf).
• The leaf gives the answer.
• For the baloon example, how big would the full tree be?