A Bi-level heuristic solution for the nurse scheduling problem based on shift-swapping

This paper presents a novel heuristic solution to the well-known Nurse Scheduling Problem (NSP). The NSP has several constraints to satisfy: some are mandatory and specified by the hospital administration, these are known as hard constraints, while other constraints are set by the nurses themselves according to their schedule preferences, these are known as soft constraints. Our solution is based on the practice of shift-swapping performed by nurses who receive an unsatisfactory schedule. The constraints are arranged in order of importance. Our technique works on two levels; first we generate a schedule that satisfies all the hard constraints and guarantees fairness. The second level is to attempt to satisfy as many of the soft constraints as possible, by shift-swapping while maintaining the hard constraints. The technique was implemented as a simulation and demonstrated a satisfactory outcome.