For a two-tailed test at the .05 significance level, the appropriate cutoff Z scores would be:
A)-1.96 and +1.96
B)-2.58 and +2.58
C)-1.64 and +1.64
D)-2.33 and +2.33

Question

Quizplus · Accepted Answer

For a two-tailed test at the .05 significance level, we need to split the alpha level equally between the two tails, with alpha/2 in each tail. This gives us an alpha level of .025 in each tail. Using a standard normal distribution table, we can find the Z scores that correspond to the upper and lower .025 levels, which are approximately +1.96 and -1.96, respectively. Therefore, the appropriate cutoff Z scores are +1.96 and -1.96.

For a Two-Tailed Test at the