Chi Square Goodness Of Fit Calculator Guide
Chi-Square Goodness of Fit
Tests whether observed categorical frequencies match expected frequencies from a hypothesized distribution.
Formula
χ² = Σ (Oᵢ − Eᵢ)² / Eᵢ, df = categories − 1 − parameters_estimated
Example
Compare observed counts to uniform expected counts and compute χ² to obtain a p-value.
FAQs
Small expected counts?
Combine categories or use exact methods.
When invalid?
Expected frequencies should generally be ≥ 5 for each cell.