X: positive

X^c: negative

$a_P$ : accept

${\lambda }_{PP}=\lambda \left(a_P|X\right)$

${\lambda }_{PN}=\lambda \left(a_P|X^c\right)$

$a_B$ : reject

${\lambda }_{BP}=\lambda \left(a_P|X\right)$

${\lambda }_{BN}=\lambda \left(a_B|X^c\right)$

$a_N$ : defer

${\lambda }_{NP}=\lambda \left(a_P|X\right)$

${\lambda }_{NN}=\lambda \left(a_N|X^c\right)$