Adaptive threshold policies for multi-channel call centers

Abstract

In the context of multi-channel call centers with inbound calls and emails, this article considers a threshold policy on the reservation of agents for the inbound calls. We study a general non-stationary model where calls arrive according to a non-homogeneous Poisson process. The optimization problem consists in maximizing the throughput of emails under a constraint on the waiting time of inbound calls. An efficient adaptive threshold policy is proposed that is easy to implement in the automatic call distributor. This scheduling policy is evaluated through a comparison with the optimal performance measures found in the case of a constant arrival rate and also with other intuitive adaptive threshold policies in the general non-stationary case.

Keywords:

• Queueing systems
• service operations
• multi-channel call centers
• threshold policies

Additional information

Notes on contributors

Benjamin Legros

Benjamin Legros is a postdoc researcher in Operations Management at Laboratoire Génie Industriel, Ecole Centrale Paris. He received a B.Sc. degree in Industrial Engineering from Ecole Centrale Paris in 2006. He carried out his Ph.D research on the optimization of multi-channel Call Centers at Ecole Centrale Paris and received a Ph.D degree in 2013. His current research interests are in stochastic modeling and operations management of call centers.

Oualid Jouini

Oualid Jouini is an assistant professor in Operations Management at Laboratoire Génie Industriel, Ecole Centrale Paris. He received a B.Sc. degree in Industrial Engineering from Ecole Nationale d’Ingénieurs de Tunis in 2001 and an M.Sc. degree in Industrial Engineering from Ecole Centrale Paris in 2003. He carried out his Ph.D research on Operations Management in Call Centers at Ecole Centrale Paris and received a Ph.D degree in 2006. His current research interests are in stochastic modeling and service operations management. His main application area is call centers and healthcare systems.

Ger Koole

Ger Koole is full professor at VU University Amsterdam. He graduated in Leiden on a thesis on the control of queueing systems. Since then he held post-doc positions at CWI Amsterdam and INRIA Sophia Antipolis. His current research is centered around service operations, especially call centers, health care, and, more recently, revenue management. Dr. Koole is founder of a call center planning company, a software company active in the area of online marketing, and of PICA, the VU University/medical center joint knowledge center on health care operations management. He teaches on the theory and applications of stochastic modeling at all levels, from Ph.D. students to professionals in call centers and hospitals.