Refining Square-Root Safety Staffing by Expanding Erlang C

• 成果类型: Article
• 署名作者: Janssen, A. J. E. M.; van Leeuwaarden, J. S. H.; Zwart, Bert
• 署名单位: Eindhoven University of Technology; University System of Georgia; Georgia Institute of Technology
• 刊物名称: OPERATIONS RESEARCH
• ISSN/ISSBN: 0030-364X
• DOI: 10.1287/opre.1110.0991
• 发表日期: 2011
• 页码: 1512-1522
• 关键词: halfin-whitt regime; heavy-traffic limits; corrected diffusion approximations; multiserver queue; Call centers; random-walk; Servers; systems; asymptotics

摘要

We apply a new corrected diffusion approximation for the Erlang C formula to determine staffing levels in cost minimization and constraint satisfaction problems. These problems are motivated by large customer contact centers that are modeled as an M/M/s queue with s the number of servers or agents. The proposed staffing levels are refinements of the celebrated square-root safety-staffing rule and have the appealing property that they are as simple as the conventional square-root safety-staffing rule. In addition, we provide theoretical support for the empirical fact that square-root safety-staffing works well for moderate-sized systems.