Modeling and solving a real-life multi-skill shift design problem

In this work, we consider the shift design problem and we define a novel, complex formulation arising from practical cases. In addition, we propose a new search method based on a fast Simulated Annealing, that, differently from previous approaches, solves the overall problem as a single-stage procedure. The core of the method is a composite neighborhood that includes at the same time changes in the staffing of shifts, the shape of shifts, and the position of breaks. Finally, we present a statistically-principled experimental analysis on a set of instances obtained from real cases. Both instances and results are available on the web for future comparisons.