The estimator [ B] ws in Eq. 66 is also a mixed Wigner/S-W transform of B, but with a complementary index r s . If B is a position operator, then B = R, and B ws = R w = R. If B is a pure electronic projection operator B = |n n|, the estimator is [ B] ws = [|n n|] s , with the expression detailed in Eq. 44. In addition, the expression of [|n n|] s in terms of the MMST variables can be found in Eq. 54.