juniorFeature Engineering
What is feature normalization using Z-score standardization?
Updated May 16, 2026
Short answer
Z-score standardization scales features to have mean 0 and standard deviation 1.
Deep explanation
Z-score transformation makes features comparable by centering them around zero and scaling based on variance. This is essential for gradient-based models and distance-based algorithms.
Real-world example
Used in credit scoring models to standardize income, age, and debt ratios.
Common mistakes
- Applying scaling before train-test split leading to leakage.
Follow-up questions
- What is Z-score formula?
- When should Z-score not be used?