Statistics and Probability Dictionary

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Alpha

With respect to estimation problems , alpha refers to the likelihood that the true population parameter lies outside the confidence interval . Alpha is usually expressed as a proportion. Thus, if the confidence level is 95%, then alpha would equal 1 - 0.95 or 0.05.

With respect to hypothesis tests , alpha refers to significance level , the probability of making a Type I error .

See also:   Statistics Tutorial: Estimation Problems | Statistics Tutorial: Hypothesis Tests