What is mean by Statistical Power?

[mehtakaushal87]

Hey guy's, I am searching for meaning, Definition on Statistical Power.
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[pramitsingh30]

Hey guy's, I am searching for meaning, Definition on Statistical Power.
Can anyone like to share information on Statistical Power?

Hey Friend,

Here are the Definition,

# The power of a statistical test is the probability that the test will reject the null hypothesis when the alternative hypothesis is true (i.e. the probability of not committing a Type II error). The power is in general a function of the possible distributions, often determined by a parameter, under the alternative hypothesis. As the power increases, the chances of a Type II error occurring decrease. The probability of a Type II error occurring is referred to as the false negative rate (ß). Therefore power is equal to 1 - ß, which is also known as the sensitivity.

Power analysis can be used to calculate the minimum sample size required so that one can be reasonably likely to detect an effect of a given size. Power analysis can also be used to calculate the minimum effect size that is likely to be detected in a study using a given sample size. In addition, the concept of power is used to make comparisons between different statistical testing procedures: for example, between a parametric and a nonparametric test of the same hypothesis.

There is also the concept of a power function of a test, which is the probability of rejecting the null when the null is true.

# Hypothesis testing is a common technique in statistics to ascertain the validity of a given condition in doubt. Since in the real world, we work with samples and not the whole population, we must be sure that a particular trait occurring in the sample is really valid in the whole population or not.

For that we conduct a hypothesis testing with two sets of opposing hypothetical conditions (null and alternative hypotheses). Then one or more of several testing techniques (Student’s t-test, z-test, f-test, c²-test, etc.) are applied to reach a convincing conclusion. The ability to correctly reject an actually false null hypothesis is called the statistical power of the test. It is measured by the probability of this rejection.

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[jitenmazee]

Hey guy's, I am searching for meaning, Definition on Statistical Power.
Can anyone like to share information on Statistical Power?

Here is the information about the Statistical Power. Please find attachment and check. I have attached a doc file contains info about Statistical Power. Hope it may help you.