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Routing and Staffing in Customer Service Chat Systems with Generally Distributed Service and Patience Times

Author

Listed:
  • Zhenghua Long

    (School of Business, Nanjing University, Nanjing 210093, China)

  • Tolga Tezcan

    (Jones Graduate School of Business, Rice University, Houston, Texas 77005)

  • Jiheng Zhang

    (Department of Industrial Engineering & Decision Analytics, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong Special Administrative Region, China)

Abstract

Problem definition : We study customer service chat (CSC) systems, in which agents can serve multiple customers simultaneously, with generally distributed service and patience times. The multitasking capability of agents introduces idiosyncratic challenges when making routing and staffing decisions. Methodology/results : To determine the dynamic matching of arriving customers with available agents, we first formulate a routing linear program (LP) based on system primitives. Inspired by the optimal solution of the routing LP, we design a parsimonious dynamic routing policy that is independent of arrival rate and service capacity information. We also use the optimal solution to develop closed-form approximations for crucial performance metrics and show that a similar LP can be utilized to make staffing decisions. Through extensive simulation experiments, we showcase the efficacy of our approximations and staffing decisions. Furthermore, under our proposed policy, the CSC system exhibits a unique stationary fluid model in which the steady-state performance measures align with our approximations. Managerial implications : The extant literature primarily focuses on Markovian systems with exponential distributions. In this paper, customers’ service and patience times are allowed to be generally distributed to agree with practical settings. Our findings indicate that the distributions have a significant impact on routing policies, staffing decisions, and system performance.

Suggested Citation

  • Zhenghua Long & Tolga Tezcan & Jiheng Zhang, 2024. "Routing and Staffing in Customer Service Chat Systems with Generally Distributed Service and Patience Times," Manufacturing & Service Operations Management, INFORMS, vol. 26(5), pages 1674-1691, September.
    • Handle: RePEc:inm:ormsom:v:26:y:2024:i:5:p:1674-1691
    DOI: 10.1287/msom.2022.0114
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    References listed on IDEAS

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