The statistical concept of power is most appropriately described as:
A) the likelihood of rejecting a null hypothesis when the true effect is of some specified size.
B) the likelihood of rejecting any null hypothesis.
C) the likelihood of correctly not rejecting a true null hypothesis.
D) the likelihood that your observed sample effect size is in the same direction as the population effect size.

Question

Quizplus · Accepted Answer

Power is the probability of correctly rejecting a false null hypothesis. In other words, it is the likelihood of detecting a true effect when there is one. Therefore, option A is the most appropriate description of power. Option B is incorrect because power is only concerned with the rejection of false null hypotheses, not every null hypothesis. Option C is incorrect because it refers to the concept of Type II error (false negative), which is related to power but not the same thing. Option D is incorrect because it refers to effect size, which is related to power but not the same thing.

The Statistical Concept of Power Is Most Appropriately Described As