8.9 Para el cociente de varianzas

\(H_{0}:\frac{\sigma _{2}^{2}}{\sigma_{1}^{2}}=cte\)

\[ T=\frac{\hat{S}_{n-1}^{2}\sigma _{2}^{2}}{\hat{S}_{m-1}^{2}\sigma _{1}^{2}}\ \ \in \ \ F_{n-1,m-1}. \]