신뢰도

\[p=\frac{R}{R+S}, q=\frac{S}{R+S}, p+q=1\]

\[\lambda_sS_s=\lambda_1S_1+\lambda_2S_s\] \[\lambda_s=\lambda_1+\lambda_2\] \[S_s=\frac{\lambda_1S_1+\lambda_2S_2}{\lambda_1+\lambda_2}\]

\[\lambda_PS_P=\lambda_1S_1\cdot\lambda_2S_2\] \[S_P=\frac{S_1S_2}{S_1+S_2}\] \[\lambda_P=\lambda_1\lambda_2(S_1+S_2)\]

\[\lambda_P=\lambda_1\lambda_2(S_1+S_2)+\lambda_1\] \[\lambda_PS_P=(\lambda_1S_1)(\lambda_2S_2)+\lambda_1K\] \[K\lt S_1=S_2\]