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Confidence Interval

\( D \, \pm \, Z_{\alpha/2} \cdot se_D \)

\( \left( \bar{Y}_2 - \bar{Y}_1 \right)\, \pm\, Z_{\alpha/2}\, \sqrt{\dfrac{s_1^2}{N_1} + \dfrac{s_2^2}{N_2}} \)