The distribution used for the hypothesis test is a new one. It is called the F-distribution, named after Sir Ronald Fisher, an English statistician. The F-statistic is a ratio (a fraction). There ar...The distribution used for the hypothesis test is a new one. It is called the F-distribution, named after Sir Ronald Fisher, an English statistician. The F-statistic is a ratio (a fraction). There are two sets of degrees of freedom; one for the numerator and one for the denominator.