Solving the INRC-II Nurse Rostering Problem by Simulated Annealing based on Large Neighborhoods

This paper proposes a local search method based on a large neighborhood to solve the static version of the problem proposed for the Second Nurse Rostering Competition (INRC-II). The search method, driven by a Simulated Annealing metaheuristic, uses a combination of neighborhoods that either changes the assignments of a nurse (working shift or day-off) or swaps the assignments of two compatible nurses, for multiple consecutive days. Computational results on the set of competition instances show that our method has been able to improve on a previous Simulated Annealing approach that uses smaller neighborhoods, and to get close to the level of the best available ones.