Rejection region for a two-tail test of µ with α = 0.05
(5%)
A
two-sided test means that α is spread between
both tails of the curve, thus:
-a middle area C of 1 − α = 95%, and
-an upper tail area of α /2 = 0.025.
-a middle area C of 1 − α = 95%, and
-an upper tail area of α /2 = 0.025.
Table C
0.025
0.025
0.25