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APPROXIMATE DYNAMIC PROGRAMMING TECHNIQUES FOR SKILL-BASED ROUTING IN CALL CENTERS*

Published online by Cambridge University Press:  30 July 2012

D. Roubos  and
S. Bhulai
D. Roubos
Affiliation:
VU University Amsterdam, De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands E-mails: d.roubos@vu.nl; s.bhulai@vu.nl
S. Bhulai
Affiliation:
VU University Amsterdam, De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands E-mails: d.roubos@vu.nl; s.bhulai@vu.nl
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Abstract

We consider the problem of dynamic multi-skill routing in call centers. Calls from different customer classes are offered to the call center according to a Poisson process. The agents are grouped into pools according to their heterogeneous skill sets that determine the calls that they can handle. Each pool of agents serves calls with independent exponentially distributed service times. Arriving calls that cannot be served directly are placed in a buffer that is dedicated to the customer class. We obtain nearly optimal dynamic routing policies that are scalable with the problem instance and can be computed online. The algorithm is based on approximate dynamic programming techniques. In particular, we perform one-step policy improvement using a polynomial approximation to relative value functions. We compare the performance of this method with decomposition techniques. Numerical experiments demonstrate that our method outperforms leading routing policies and has close to optimal performance.

Type
Research Article
Information
Probability in the Engineering and Informational Sciences , Volume 26 , Issue 4 , October 2012 , pp. 581 - 591
Copyright
Copyright © Cambridge University Press 2012

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Footnotes

*

This study is an addendum to [3].

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