What is a decision tree?

Updated May 17, 2026

Short answer

Decision tree splits data based on feature conditions.

Deep explanation

It recursively splits dataset to minimize impurity using Gini or entropy.

Real-world example

Used in credit approval systems.

Common mistakes

  • Allowing deep trees causing overfitting.

Follow-up questions

  • What is Gini impurity?
  • How to prune trees?

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