Chi-Square Goodness-of-Fit Calculator
Calculate the chi-square goodness-of-fit statistic from observed and expected category counts.
Calculate the chi-square goodness-of-fit statistic from observed and expected category counts.
Move between weighted summaries, t statistics, chi-square goodness-of-fit and one-way ANOVA calculations.
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Open calculatorCalculate the chi-square goodness-of-fit statistic from observed and expected category counts.
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Open calculatorCalculate the chi-square goodness-of-fit statistic from observed and expected category counts.
Enter compatible statistical values. The calculator validates the inputs and applies χ² = Σ((Oᵢ − Eᵢ)² / Eᵢ), with df = k − 1 when no parameters are estimated from the data.
Variables: Oᵢ = Observed counts; Eᵢ = Expected counts.
Example: Observed counts 20, 30, 50 and expected counts 25, 25, 50 give χ²=2 with 2 degrees of freedom.
It is an educational tool for descriptive and inferential statistical calculations from supplied values or summary statistics.
No. Where a test statistic is calculated, the tool does not automatically replace study design, assumption checks, p-value interpretation, confidence intervals or subject-matter judgment.
These sources are used to verify terminology, formulas, and information related to this calculator.