Comparison of quantum binary experiments

Understand

A quantum binary experiment consists of a pair of density operators on a finite dimensional Hilbert space.

• An experiment E is called \epsilon-deficient with respect to another experiment F if, up to \epsilon, its risk functions are not worse than the risk functions of F, with respect to all statistical decision problems.
• It is known in the theory of classical statistical experiments that 1.
• for pairs of probability distributions, one can restrict to testing problems in the definition of deficiency and 2.