Paired Z-Test of Means

From Q
Jump to: navigation, search

Where \bar x_1 and \bar x_2 are the two means, the test statistic is:

z=\frac{\bar x_1-\bar x_2}{s_{{\bar x_1} - {\bar x_2}}}


p \approx 2(1-\Phi(|z|)),
s_{{\bar x_1} - {\bar x_2}} is computed as the Standard Error of d,
the value for the ith observation is computed as d_i = x_{i1} - x_{i2}, and
x_1,x_2 are the observed values on the two variables.