Integer programming model extensions for a multi-stage nurse rostering problem

In the variant of the well studied nurse rostering problem proposed in the Second International Nurse Rostering Competition, multiple stages have to be solved sequentially which are dependent on each other. We propose an integer programming model for this problem and show that a set of newly developed extensions in the form of additional constraints to deal with the incomplete information can significantly improve the quality of the generated solutions. We compare our solution approaches with the results obtained in the competition and show that the extended model achieves results competitive with the competition finalists.