Performance analysis of an inbound call center with skills-based routing

A priority queueing system with two classes of impatient customers and heterogeneous agents


Many call centers provide service for customers of different classes with differently qualified groups of agents. Since call arrivals and call handling times are random in inbound call centers, we investigate queueing models for their performance analysis. This paper describes a Markov queueing model with two customer classes and three groups of specialized or flexible agents. The mean call handling time may depend on the respective customer class as well as on the agent group serving this call. The customers are assumed to be impatient. We consider skills-based routing with priority-based rules and derive both steady-state probabilities and performance measures. We present some numerical experiments and show the impact of different mean processing times. The influence of the allocation of the agents into the three groups is analyzed for different levels of patience.

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Correspondence to Raik Stolletz.

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Correspondence to: Raik Stolletz .

R. Stolletz, S. Helber: The authors thank the anonymous referees for their helpful comments and suggestions.

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Stolletz, R., Helber, S. Performance analysis of an inbound call center with skills-based routing. OR Spectrum 26, 331–352 (2004).

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  • Call center
  • Performance evaluation
  • Impatient customers
  • Flexible and specialized server
  • Nonpreemptive priority queueing