chi-square goodness of fit statistic
compares the observed frequency of a category with the model expected frequency.
symbols, variables and units
O_i: observed frequency; E_i: expected frequency; χ²: dimensionless.
applicable conditions and boundaries
Each E_i>0; the chi-square asymptotic test requires sufficient expected frequency and adjusts the estimated parameter degrees of freedom.
formula source code
The following is a copyable LaTeX expression.
\chi^2=\sum_i\frac{(O_i-E_i)^2}{E_i}Reference and Extended Learning
NIST/SEMATECH · e-Handbook of Statistical Methods ↗is organized according to model definition and assumptions. Please check actual conditions and original literature before engineering, research and clinical use.
chi squaregoodness of fit