Telephone Call Centers : a Tutorial and Literature Review

Telephone call centers are an integral part of many businesses, and their economic role is significant and growing. They are also fascinating socio-technical systems in which the behavior of customers and employees is closely intertwined with physical performance measures. In these environments traditional operational models are of great value – and at the same time fundamentally limited – in their ability to characterize system performance. We characterize the state of research on telephone call centers. We begin with a tutorial on how call centers function and proceed to survey academic research devoted to the management of their operations. We then outline important problems that have not been addressed and identify promising directions for future research. Acknowledgments The authors thank Lee Schwarz, Wallace Hopp and the editorial board of M&SOM for initiating this project. Thanks are also due to L. Brown, A. Sakov, H. Shen, S. Zeltyn and L. Zhao for their approval of importing pieces of [33, 106]. Financial support was provided by NSF Grants SBR-9733739 and DMI-0223304 (N.G. and A.M.), the Wharton Financial Institutions Center (N.G. and A.M.), ISF Grants (A.M., jointly with N. Shimkin and R. Atar), and the Technion funds for the promotion of research and sponsored research (A.M.) Some data originated with member companies of the Call Center Forum at Wharton, to whom we are grateful. Some material was adapted from the Service Engineering site prepared by A.M. and S. Zeltyn (http://ie.technion.ac.il/serveng/). Parts of the manuscript were written while A.M. was visiting the Vrije Universiteit and the Wharton School – the hospitality of the hosting institutions is greatly appreciated.

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