What is interaction feature engineering?

Updated May 16, 2026

Short answer

Interaction features combine two or more variables to capture joint effects.

Deep explanation

Interaction features capture relationships that individual variables cannot express alone. For example, income and age together may better predict spending behavior than either alone. These features help linear models approximate non-linear relationships.

Real-world example

Used in marketing to understand how age and income jointly affect purchase behavior.

Common mistakes

  • Creating too many interactions leading to feature explosion.

Follow-up questions

  • What is difference between polynomial and interaction features?
  • Do tree models need interaction features?

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