Assuming a collection of particles for which θ θ is known as being either less than or greater than π π / 4 the Procrustean method may be carried out by keeping all particles which, when passed through a polarization-dependent absorber, or a polarization-dependent-reflector, which absorb or reflect a fraction tan 2 ⁡ ⁡ θ θ of the more likely outcome, are not absorbed or deflected. Therefore, if Alice possesses particles for which θ θ ≠ ≠ π π / 4 , she can separate out particles which are more likely to be measured in the up/down basis, and left with particles in maximally mixed state of spin up and spin down. This treatment corresponds to a POVM (positive-operator-valued measurement). To obtain a perfectly entangled state of two particles, Alice informs Bob of the result of her generalized measurement while Bob doesn't measure his particle at all but instead discards his if Alice discards hers.