## Statistics (12th Edition)

$\bar x_{d} = 2$ $s^{2}_{d} = 2$
Difference 7 - 4 = 3 3 - 1 = 2 9 - 7 = 2 6 - 2 = 3 4 - 4 = 0 8 - 7 = 1 $\bar x_{d} = \frac{3+ 2+ ... + 1}{6} = 2$s^{2}_{d} = \frac{(3-2)^2 + .... + (1 - 2)^{2}}{6 - 1} = 2