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How to Calculate a Z-Score
Formula
A z-score measures how many standard deviations a value is from the mean.
A z-score of 0 means the value equals the mean; positive values are above and negative are below.
Common use cases:
- Comparing scores from different distributions
- Identifying statistical outliers
- Standardizing data for analysis
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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