Chi-Square Test of a Frequency Distribution

Tests the null hypothesis that the observed values of a categorical variable diff from the expected values. The test statistic is

[math]\displaystyle{ X^2 = \sum^s_{k=1} \frac{(o_{kj} - e_{kj})^2}{e_{kj}} }[/math]

where:

[math]\displaystyle{ o_{k} }[/math] are the observed values,

[math]\displaystyle{ e_{k} = }[/math] are the expected values,

[math]\displaystyle{ p \approx \Pr(\chi^2_{(s-1)} \ge X^2) }[/math]

See also

• ANOVA-Type Tests - Comparing Three or More Groups
• Planned ANOVA-Type Tests
• Second Order Rao-Scott Test of Independence of a Contingency Table