What is train-test split in classification?

Updated May 15, 2026

Short answer

Train-test split divides data into training and evaluation sets.

Deep explanation

It ensures unbiased evaluation by testing model performance on unseen data.

Real-world example

Evaluating a fraud detection model before deployment.

Common mistakes

  • Testing on training data leading to inflated performance.

Follow-up questions

  • What is cross-validation?

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