Question

Define power. What is its importance in hypothesis?

Answer 1

Definition. The power of a hypothesis test is theprobability of making the correct decision if thealternative hypothesis is true. That is, the power of a hypothesis test is the probability of rejecting thenull hypothesis H₀ when the alternative hypothesis H_A is the hypothesis that is true.

The power of any test of statistical significance is defined as the probability that it will reject a false null hypothesis. Statistical power is inversely related to beta or the probability of making a Type II error. In short, power = 1 – β