A multi-level bottleneck assignment approach to the bus drivers' rostering problem

The problem of finding a work assignment for drivers in a given time horizon, in such a way as to have an even distribution of the workload, is considered. This problem is formulated as a Multi-level Bottleneck Assignment Problem (MBA). The MBA problem is studied: it is shown that it is NP-complete and an asymptotically optimal algorithm is presented. Some computational results are illustrated which prove the efficiency of the algorithm.