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Staffing a service system with appointment-based customer arrivals


Appointment systems are widely used to facilitate customers’ access to services in many industries such as healthcare. A number of studies have taken a queueing approach to analyse service systems and facilitate managerial decisions on staffing requirements by assuming independent and stationary customer arrivals. This paper is motivated by the observation that the queueing-based method shows relatively poor performance when customers arrive according to their appointment times. Because customer arrivals are dependent on their appointment times, this study, unlike queueing-based methods, conducts a detailed analysis of appointment-based customer arrivals instead of making steady-state assumptions. We develop a new model that captures the characteristics of appointment-based customer arrivals and computes the probability of transient system states. Through the use of this model, which relaxes stationary and independent assumptions, we propose a heuristic algorithm that determines staffing requirements with aims to minimizing staff-hours while satisfying a target service level. The simulation results show that the proposed method outperforms the queueing-based method.

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This work was supported by the Hongik University new faculty research support fund.

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Correspondence to Daiki Min.

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Chung, K., Min, D. Staffing a service system with appointment-based customer arrivals. J Oper Res Soc 65, 1533–1543 (2014).

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  • service system
  • staffing requirements
  • appointment-based customer arrival
  • heuristic algorithm