Suppose I run the Qiskit's QAOA algorithm.
qaoa = QAOA(operator=qubit_operator, p=p, optimizer=optimizer)
result = qaoa.run(quantum_instance)
There is a built-in method that gets me the most likely binary solution for this problem. sample_most_likely(result['eigenstate'])
But how do I get the whole probability distribution of binary solutions? Ultimately, I would like to calculate the expected value for my problem, not the value based solely on the most likely string.