Staffing of Time-Varying Queues to Achieve Time-Stable Performance

Continuing research by Jennings, Mandelbaum, Massey and Whitt (1996), we investigate methods to perform time-dependent staffing for many-server queues. Our aim is to achieve time-stable performance in face of general time-varying arrival rates. It turns out that it suffices to target a stable probability of delay. That procedure tends to produce time-stable performance for several other operational measures. Motivated by telephone call centers, we focus on many-server models with customer abandonment, especially the Markovian Mt/M/st + M model, having an exponential time-to-abandon distribution (the +M), an exponential servicetime distribution and a nonhomogeneous Poisson arrival process. We develop three different methods for staffing, with decreasing generality and decreasing complexity: First, we develop a simulation-based iterativestaffing algorithm (ISA), and conduct experiments showing that it is effective. The ISA is appealing because it applies to very general models and is au...

• Type: Journal
• Year: 2008
• Where: MANSCI
• Authors: Zohar Feldman, Avishai Mandelbaum, William A. Massey, Ward Whitt
• Keywords: Arrival Rate, MANSCI 2008, Many-server Queues, Time-stable Performance