What is normalization in recommendation systems?

Updated May 16, 2026

Short answer

Normalization adjusts rating scales to remove user bias.

Deep explanation

Users rate differently; some are generous while others are strict. Normalization adjusts ratings by subtracting user mean or scaling values to make comparisons fair.

Real-world example

Adjusting movie ratings across different users.

Common mistakes

  • Ignoring user bias in ratings.

Follow-up questions

  • What is z-score normalization?
  • Why normalize?

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