Analysis of a Call Center with Partial Closing Rules, Feedback and Impatient Calls

have been used in call centers widely in recent years. In this paper, we study a call center made up of trunk lines, IVRUs and Customer Service Representatives(CSRs). We discuss partial closing rules, calls’ impatience and feedback phenomena in a call center. A call enter the call center whenever a trunk line is available, otherwise it is lost. Once a trunk line is seized, the call is served by the IVRUs first; then the call may leave the center or be routed to an available CSRs. If all CSRs are busy, the call is queued at the automatic call distributor until one line is free. While waiting for CSRs, calls may abandon the queue if their waiting time becomes unreasonably long. We assume that each call abandons the queue independently of each other when waiting for CSRs. From the perspective of the queuing theory, we present some significant performance measures for the system in steady-state. Finally, numerical results are presented with the focus on the effects of different parameters.