Journal of Applied Mathematics and Decision Sciences
Volume 2006 (2006), Article ID 53928, 13 pages

Synergistic modeling of call center operations

Dennis C. Dietz and Jon G. Vaver

Qwest Communications International, Boulder 80301, CO, USA

Received 14 July 2005; Revised 30 November 2005; Accepted 9 December 2005

Copyright © 2006 Dennis C. Dietz and Jon G. Vaver. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


We synergistically apply queueing theory, integer programming, and stochastic simulation to determine an optimal staffing policy for a repair call handling center. A stationary Markovian queueing model is employed to determine minimal staffing levels for a sequence of time intervals with varying call volumes and mean handling times. These staffing requirements populate an integer program model for determining the mix of call agent shifts that will achieve service quality standards at minimum cost. Since the analytical modeling requires simplifying assumptions, expected performance of the optimal staffing policy is evaluated using stochastic simulation. Computational efficiency of the simulation is improved dramatically by employing the queueing model to generate an analytic control variate.