Two-Sample Z-Test for p₁−p₂¶
Overview¶
Tests whether two population proportions differ.
Test Statistic¶
\[
Z = \frac{\hat{p}_1 - \hat{p}_2}{\sqrt{\hat{p}(1-\hat{p})(1/n_1 + 1/n_2)}}
\]
where \(\hat{p} = (X_1 + X_2)/(n_1 + n_2)\) is the pooled proportion under \(H_0: p_1 = p_2\).