n
nicefa.
Intermediate Proof

Ratio of Two Variances: Comparing Spread

Students frequently confuse the order of degrees of freedom. The numerator sample size n11 n_1 - 1 must correspond to the numerator variance S12 S_1^2 . Also, always ensure your sample data is normally distributed; the F F -test is notoriously sensitive to deviations from normality.
Institutional Reference: Statistical Inference I
View Full Proof →