Type I and Type II Error Calculator
Error Rate Analysis
Alpha-Beta Tradeoff
Formula
Beta = 1 - Power. Family-wise alpha = 1 - (1-alpha)^k. Bonferroni alpha = alpha/k
Frequently Asked Questions
What is a Type I error?
A Type I error (false positive) occurs when you reject the null hypothesis when it is actually true. The probability is alpha, typically 0.05.
What is a Type II error?
A Type II error (false negative) occurs when you fail to reject a false null hypothesis. The probability is beta. Power = 1 - beta.
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