What determines the decision of whether to use a one-tailed test or a two-tailed test when testing hypotheses to make inferences about a population mean?
A)the sample size and the estimated standard error
B)the nature of the situation and what the researcher is trying to demonstrate
C)the level of significance of the test
D)the sample size relative to the population size
E)the standard error relative to the sample variance

Question

Quizplus · Accepted Answer

The decision to use a one-tailed test or a two-tailed test depends on the nature of the situation and what the researcher is trying to demonstrate. A one-tailed test is used when the researcher is interested in either a specific direction of difference or knows in advance the direction of the difference. For example, if the researcher is testing a hypothesis that a new treatment will be more effective than an existing treatment, a one-tailed test would be appropriate. On the other hand, a two-tailed test is used when the researcher is interested in detecting any difference from the null hypothesis, regardless of the direction. For example, if the researcher is investigating whether there is a difference in the mean weight of apples between two farms, a two-tailed test would be appropriate. The level of significance also plays a role in the decision, but it is not the determining factor.

What Determines the Decision of Whether to Use a One-Tailed