Type I error

Type I error or alpha (α) error refers to an erroneous rejection of the null hypothesis (H₀).

In research, the first step of statistical testing is the setting of hypotheses. A type I error occurs when the H₀ is rejected. Type I errors are also known as ‘false positives’; they are the detection of a positive effect where no effect actually exists.

See also: type II error

Type I and Type II Errors and Statistical Power (StatPearls, 2023)

Type I and Type II Errors in Statistical Decision (Restorative Dentistry and Endodontics, 2015)

Controlling Type I Error rates in Multi-Arm Clinical Trials: A Case for the False Discovery Rate, 2020)