Statistics and Probability Dictionary
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Type II Error
Two types of errors can result from a
Type I error. A Type I error occurs when the researcher
rejects a null hypothesis
when it is true. The probability of committing a Type I error is called the
, and is often denoted by α.
Type II error. A Type II error occurs when the researcher
accepts a null hypothesis that is false. The probability of committing a Type
II error is called Beta, and
is often denoted by β. The probability of not
committing a Type II error is called the
of the test.