What is feature importance in Random Forest?

Updated May 17, 2026

Short answer

Feature importance measures how much each feature contributes to predictions.

Deep explanation

It is computed based on impurity reduction across all trees. Higher importance means stronger influence on prediction.

Real-world example

Used in marketing to identify key customer behavior drivers.

Common mistakes

  • Assuming importance implies causation.

Follow-up questions

  • Is it biased?
  • Are there better methods?

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