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Math & AlgebraGenerated accuracy model review: 2026-05-06
Z-Score Calculator accuracy and testing
This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.
Formula source
- **Z = (x - μ) / σ** * **x**: The raw score * **μ**: The mean of the population * **σ**: The standard deviation of the population
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- Raw Score (x): 85
- Mean (μ): 75
- Standard Deviation (σ): 10
Expected outputs
- Z-Score: 1
Known limitations
- This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
- Use the result as a planning estimate unless the calculator page states a stricter purpose.
Assumptions
- The standard deviation must be greater than zero for the z-score formula to be valid.
- This calculator standardizes a single observed value against the mean and standard deviation you provide.
- Interpretations about percentiles and outliers are most useful when the underlying distribution is roughly normal.
Unit handling
- Raw Score (x) accepts numeric values.
- Mean (μ) accepts numeric values.
- Standard Deviation (σ) accepts numeric values.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current z-score-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for Z-Score Calculator.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.