1. The problem statement, all variables and given/known data OK, so assuming we have a physical observable with three values, a(1),a(2) and a(3), and there are given matrices for the measurement operators M(a(1))...M(a(3)). How does one actually go about finding a(1),a(2) and a(3) given the matrices? 3. The attempt at a solution These measurement operators have to be hermitian, and thus have real eigenvalues. Are the values of the three observables a(n) just the eigenvalues of the measurement operators? All three are in the same basis, by the way.