Reject Region and Critical Values #1

Question

Assuming that the population standard deviation is unknown for a

randomly selected sample whose size is 11, sketch the rejection region

for a one-tailed test with 99% confidence. Does t = 2.86 fall in the

rejection region?

Answer 1

For 99% confidence, the level of significance (alpha) is 0.01 Since t = 2.86 is positive, will assume that a right tail test is being performed. The critical t-value for 11 - 1 = 10 degrees of freedom and alpha = 0.01 is 2.764, The rejection region is > 2.764 so t = 2.86 falls in the rejection region.