Critical Thinking: One-Tailed versus Two-Tailed Tests

(a) For the same data and null hypothesis, is the P-value of a one-tailed test (right or left) larger or smaller than that of a two-tailed test? Explain.

(b) For the same data, null hypothesis, and level of significance, is it possible that a one-tailed test results in the conclusion to reject H0 while a twotailed test results in the conclusion to fail to reject H0? Explain.

(c) For the same data, null hypothesis, and level of significance, if the conclusion is to reject H0 based on a two-tailed test, do you also reject H0 based on a one-tailed test? Explain.

(d) If a report states that certain data were used to reject a given hypothesis, would it be a good idea to know what type of test (one-tailed or two-tailed)
was used? Explain.AppendixLO1