Manpower scheduling of hospital call center: a multi-objective multi-stage optimization approach

This research investigates the solution approach for scheduling staff in a call center to determine the appropriate staff schedules in order to minimize workforce costs while meeting the target level of service quality. In this regard, a multi-objective multi-stage integer mathematical model is developed to determine the optimal schedules for the staff. The first objective aims to minimize the maximum understaffing, and the second objective minimizes the weighted sum of understaffing and overstaffing to create a balance between these two conflicting objectives. The first stage of the model is devoted to full-time (FT) and part-time (PT) staff scheduling, and the second stage of the model determines the schedules for the Per Diem staff (referred to as PRNs in this study). This model considers several constraints and aspects of the problem that include employees' days off, lunch breaks, preferences, etc. The lexicographic method and weighted sum approach are used to solve the models. Results show that the optimal schedules obtained from the models outperform the current practice of the call center and significantly reduce the maximum/total sum of overstaffing and understaffing over the planning horizon.