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The ability for a study to reveal a statistically significant difference between the levels of an independent variable when one truly exists is known as power. A statistical test's power is the probability that rejecting the null hypothesis is valid. It can be calculated by the expression Power = 1 - beta where beta is the probability of a type II error.
Fixed population:San Antonio Residents
Dynamic population : Women who have had hysterectomies by age 45
Fixed population : Children who developed autism in 2009
Dynamic population : Public health graduate students majoring in epidemiology
