Likelihood Theory in a Quantum World: tests with Quantum coins and
  computers
By repeated trials, one can determine the fairness of a classical coin with a
confidence which grows with the number of trials. A quantum coin can be in a
superposition of heads and tails and its state is most generally a density
matrix. Given a string of qubits representing a series of trials, one can
measure them individually and determine the state with a certain confidence. We
show that there is an improved strategy which measures the qubits after
entangling them, which leads to a greater confidence. This strategy is
demonstrated on the simulation facility of IBM quantum computers.
Arpita Maitra Joseph Samuel Supurna Sinha