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definitions

Type I error

noun
  1. the error made in the statistical testing of a hypothesis by rejecting the null hypothesis when it is actually true.

Origin of Type I error

First recorded in 1960–65
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for type i error

type I error

noun
  1. statistics the error of rejecting the null hypothesis when it is true, the probability of which is the significance level of a result
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012