The F-statistic is calculated as: \[ F = \frac{\max(s_1^2, s_2^2)}{\min(s_1^2, s_2^2)} \] Following an F-distribution with \(d_1\) and \(d_2\) degrees of freedom.
Critical value \(F_{critical}\) satisfies: \[ P(F \leq F_{1-\alpha}; d_1, d_2) = 1 - \alpha \] Calculated using the regularized incomplete beta function.