Scheduling Agents Using Forecast Call Arrivals at Hydro-Québec’s Call Centers

  • Marie Pelleau
  • Louis-Martin Rousseau
  • Pierre L’Ecuyer
  • Walid Zegal
  • Louis Delorme
Part of the Lecture Notes in Computer Science book series (LNCS, volume 8656)


The call center managers at Hydro-Québec (HQ) need to deliver both low operating costs and high service quality. Their task is especially difficult because they need to handle a large workforce (more than 500 employees) while satisfying an incoming demand that is typically both time-varying and uncertain. The current techniques for determining the schedule of each employee according to the forecast call volumes at HQ are often unreliable, and there is a need for more accurate methods. In this paper, we address the concerns of the call center managers at HQ by modeling the problem of multi-activity shift scheduling. This model has been implemented and tested using real-life call center data provided by HQ.The main contribution of this paper is to demonstrate that a constraint programming (CP) model with regular language encoding can solve large problems in an industrial context. Furthermore, we show that our CP-based formulation has considerably better performance than a well-known commercial software package.


Column Generation Call Center Constraint Programming Current Tool Schedule Agent 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Marie Pelleau
    • 1
  • Louis-Martin Rousseau
    • 2
  • Pierre L’Ecuyer
    • 1
  • Walid Zegal
    • 3
  • Louis Delorme
    • 3
  1. 1.Université de MontréalMontrealCanada
  2. 2.Polytechnique MontréalMontrealCanada
  3. 3.Institut de recherche d’Hydro-QuébecMontrealCanada

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