Robust Shift Scheduling in Call Centers

We propose a robust optimization model for shift scheduling in call centers. The model is designed to react to the deviations that often occur between the planned staffing levels and the actual number of employees that would be necessary to guarantee the desired level of service. Different perturbation patterns are considered giving rise to different uncertainty sets, and the corresponding algorithmic implications are discussed. A case study from an Italian Public Agency is finally presented, which shows how the proposed methodology improves the quality of the schedules. Interestingly, although the methodology is fairly sophisticated, it perfectly fits in a quite common managers current practice.

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