Why do decision trees struggle in high dimensions?

Updated May 15, 2026

Short answer

They become too deep and overfit noise.

Deep explanation

High-dimensional spaces increase split possibilities, leading to fragmented decision boundaries.

Real-world example

Customer churn prediction with many weak features.

Common mistakes

  • Not pruning trees.

Follow-up questions

  • How to fix overfitting?
  • Are ensembles better?

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