  We present an error mitigation scheme which corrects readout errors on Noisy
Intermediate-Scale Quantum (NISQ) computers [1,2]. After a short review of
applying the method to one qubit, we proceed to discuss the case when
correlations between different qubits occur. We demonstrate how the readout
error can be mitigated in this case. By performing experiments on IBMQ
hardware, we show that such correlations do not have a strong effect on the
results, justifying to neglect them.
