A Performance Analysis of Call Centers Based on a Multi-Server Queue With Retrials, Feedbacks, and Impatience

The authors consider a finite buffer queueing model with several key features of call centers, such as retrials, feedbacks, and impatience. In addition, because they do not completely understand the customer impatience behavior, they use a general distribution for the maximum waiting time before abandoning the call. The authors develop a QBD process with infinite state space for the queue in a call center situation. To solve for the stationary performance measures, they introduce an effective approximation method, and numerical examples have been presented to show the effectiveness of the method.