17.8 Power and Sample Size (Pro Only)

The power of a test is the probability of rejecting the null hypothesis when the alternate hypothesis is true. Such tests are used to determine whether an experiment is likely to yield useful information with a given sample size. Conversely, power analysis can be useful in determining the minimum sample size needed to produce a statistically significant experiment.

Power and sample size computations are test-dependent. That is, if the initial hypothesis test is a one-sample t test, then the power and sample size computations must be based on that test; otherwise, the results may be incorrect.

OriginPro includes power and sample size computations with the following tests.

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