Statistical significance
The concept of statistical significance was originated by Ronald Fisher in his 1925 publication, Statistical Methods for Research Workers, when he developed statistical hypothesis testing (which he described as "tests of significance"). Fisher suggested a probability of one in twenty (0.05 or 5%)—as a convenient cutoff level to reject the null hypothesis. In their 1933 paper, Jerzy Neyman and Egon Pearson recommended that the significance level (for example 0.05), which they called α, be set before any data collection.