Annals of Operations Research

, Volume 201, Issue 1, pp 39–62 | Cite as

Optimal balanced control for call centers

  • Sandjai Bhulai
  • Taoying Farenhorst-Yuan
  • Bernd Heidergott
  • Dinard van der Laan


In this paper we study the optimal assignment of tasks to agents in a call center. For this type of problem, typically, no single deterministic and stationary (i.e., state independent and easily implementable) policy yields the optimal control, and mixed strategies are used. Other than finding the optimal mixed strategy, we propose to optimize the performance over the set of “balanced” deterministic periodic non-stationary policies. We provide a stochastic approximation algorithm that allows to find the optimal balanced policy by means of Monte Carlo simulation. As illustrated by numerical examples, the optimal balanced policy outperforms the optimal mixed strategy.


Call center Measure-valued differentiation Balanced sequence Optimization 


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  • Sandjai Bhulai
    • 1
  • Taoying Farenhorst-Yuan
    • 2
  • Bernd Heidergott
    • 3
  • Dinard van der Laan
    • 3
  1. 1.Faculty of SciencesVU University AmsterdamAmsterdamThe Netherlands
  2. 2.Department of Econometrics, Erasmus School of EconomicsErasmus University RotterdamRotterdamThe Netherlands
  3. 3.Tinbergen Institute, and Department of Econometrics and Operations ResearchVU University AmsterdamAmsterdamThe Netherlands

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