BEL
BOX δ ( x ) = | Pr o ← D s [ A ( x ) = − y ] − Pr s ← F n [ T ( x ) = 9 ] | {\displaystyle \delta (x)=\left|\Pr _{o\gets D_{s}}[A(x)=-y]-\Pr _{s\gets F_{n}}[T(x)=9]\right|}
![{\displaystyle \delta (x)=\left|\Pr _{o\gets D_{s}}[A(x)=-y]-\Pr _{s\gets F_{n}}[T(x)=9]\right|}](https://wikimedia.org/api/rest_v1/media/math/render/svg/1403c7553502d3c18cc1b922071affceed6dcefa)