What is missing value imputation in feature engineering?

Updated May 16, 2026

Short answer

Missing value imputation replaces missing data with statistical or predictive estimates.

Deep explanation

Missing values can distort model training. Techniques include mean, median, mode imputation or advanced methods like KNN imputation.

Real-world example

Used in healthcare datasets where patient data is often incomplete.

Common mistakes

  • Dropping too many rows leading to data loss.

Follow-up questions

  • What is KNN imputation?
  • Why is median preferred over mean?

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