Which of these statements is correct about one- and two-tailed tests?
A) A statistical model that tests a directional hypothesis is called a one-tailed test, whereas one testing a non-directional hypothesis is called a two-tailed test
B) A statistical model that tests a non-directional hypothesis is called a one-tailed test, whereas one testing a directional hypothesis is called a two-tailed test.
C) A two-tailed test is a more powerful test than a one-tailed test.
D) A one-tailed test is a more accurate test than a two-tailed test.

Question

Quizplus · Accepted Answer

A one-tailed test is used to test a directional hypothesis, where the researcher has a specific expectation of the direction of the effect. A two-tailed test is used to test a non-directional hypothesis, where the researcher does not have a specific expectation of the direction of the effect. Therefore, statement A is correct. Statement B is incorrect. Statement C is not always true, as the power of the test depends on several factors, such as sample size and effect size. Statement D is also incorrect as a one-tailed test is not necessarily more accurate than a two-tailed test.

Which of These Statements Is Correct About One- and Two-Tailed