Flexible Staffing for Call Centers with Non-stationary Arrival Rates

  • Alex RoubosEmail author
  • Sandjai Bhulai
  • Ger Koole
Part of the International Series in Operations Research & Management Science book series (ISOR, volume 248)


We consider a multi-period staffing problem of a single-skill call center. The call center is modeled as a multi-server queue in which the staffing levels can be changed only at specific moments in time. The objective is to set the staffing levels such that a service level constraint is met in the presence of time-varying arrival rates. We develop a Markov decision model to obtain time-dependent staffing levels for both the case where the arrival rate function is known as well as unknown. The characteristics of the optimal policies associated to the two cases are illustrated through a numerical study based on real-life data. We show that the optimal policies provide a good balance between staffing costs and the penalty probability for not meeting the service level.

Key words

Call centers Markov decision processes Staffing Time-varying arrival rates 


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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.CCmathAmsterdamThe Netherlands
  2. 2.Faculty of SciencesVrije Universiteit AmsterdamAmsterdamThe Netherlands

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