Stat Tools

1-Sample Variance Test

Analyze Phase

Test whether the variance (or standard deviation) of your process is significantly different from a target or historical value. Uses the chi-square distribution. Critical for verifying process consistency and meeting specification tolerances.

Data Table
Paste data directly from Excel or Google Sheets — columns and rows will be imported automatically.
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e.g. 1.0 (enter σ² not σ)

Hypotheses

H₀: σ² = σ₀² = 1

H₁: σ² ≠ σ₀² (two-tailed)

Test statistic: χ² = (n−1)·s² / σ₀², follows a chi-square distribution with df = n−1.

Load data with at least 2 values to run the test

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