An advanced queueing model to analyze appointment-driven service systems.

Many service systems are appointment-driven. In such systems, customers make an appointment and join an external queue (also referred to as the “waiting list”). At the appointed date, the customer arrives at the service facility and receives service. Important measures of interest include the size of the waiting list as well as the time spent in the waiting list. We develop a model to assess these performance measures. The model may be used to support strategic decisions concerning server capacity (e.g. how often should a server be online, how many customers should be served during each service session, ...). The model is a vacation model that uses efficient algorithms and matrix analytical techniques to obtain waiting list performance measures.Appointment system; Vacation model; Waiting list; Queueing system; Algorithm;