If both distributions are normal, then the ratio of the two sample variances is distributed as an \(F\) statistic, with numerator and denominator degrees of freedom that are one less than the samples ...If both distributions are normal, then the ratio of the two sample variances is distributed as an \(F\) statistic, with numerator and denominator degrees of freedom that are one less than the samples sizes of the corresponding two groups. The ratio of these two is the \(F\) statistic from an \(F\) distribution with (number of groups – 1) as the numerator degrees of freedom and (number of observations – number of groups) as the denominator degrees of freedom.
The ratio of these two is the \(F\) statistic from an \(F\) distribution with (number of groups – 1) as the numerator degrees of freedom and (number of observations – number of groups) as the denomina...The ratio of these two is the \(F\) statistic from an \(F\) distribution with (number of groups – 1) as the numerator degrees of freedom and (number of observations – number of groups) as the denominator degrees of freedom. When the null hypothesis of equal group means is incorrect, then the numerator should be large compared to the denominator, giving a large \(F\) statistic and a small area (small \(p\)-value) to the right of the statistic under the \(F\) curve.
