A systematic two phase approach for the nurse rostering problem
European Journal of Operational Research
Article Link
Valouxis, C. G., Christos; Goulas, George; Alefragis, Panayiotis; Housos, Efthymios. (2012). A systematic two phase approach for the nurse rostering problem. [Journal Article]. European Journal of Operational Research, 219(2), 425-433. doi: 10.1016/j.ejor.2011.12.042
Nurse rostering is an NP-hard combinatorial problem which makes it extremely difficult to efficiently solve real life problems due to their size and complexity. Usually real problem instances have complicated work rules related to safety and quality of service issues in addition to rules about quality of life of the personnel. For the aforementioned reasons computer supported scheduling and rescheduling for the particular problem is indispensable. The specifications of the problem addressed were defined by the First International Nurse Rostering Competition (INRC2010) sponsored by the leading conference in the Automated Timetabling domain, PATAT-2010. Since the competition imposed quality and time constraint requirements, the problem instances were partitioned into sub-problems of manageable computational size and were then solved sequentially using Integer Mathematical Programming. A two phase strategy was implemented where in the first phase the workload for each nurse and for each day of the week was decided while in the second phase the specific daily shifts were assigned. In addition, local optimization techniques for searching across combinations of nurses