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.

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

Word History and Origins

Origin of Type I error¹

First recorded in 1960–65

Example Sentences

Risk-averse FDA reviewers have traditionally focused on avoiding what the agency knows as a Type I error: Approving a drug that isn’t safe or effective.

From Wall Street Journal

A Type I error occurs when a true hypothesis is rejected, and a Type II error occurs when a false hypothesis is accepted.

From Literature

On the other hand, if we didn’t realize that most of the Corvettes in the region weren’t driven but were kept in garages, then in rejecting the true assumption we would be making a Type I error.

From Literature

In statistics, a problem akin to apophenia is a Type I error, or false positive.

From Slate

In the 20th century it was believed that a Type I error was worse than a Type II error.

From Washington Post