Integer programming techniques for educational timetabling

Educational timetabling problems require the assignment of times and resources to events, while sets of required and desirable constraints must be considered. The XHSTT format was adopted in this work because it models the main features of educational timetabling and it is the most used format in recent studies in the eld. This work presents new cuts and reformulations for the existing integer programming model for XHSTT. The proposed Email addresses: [email protected] (George H. G. Fonseca), [email protected] (Haroldo G. Santos), [email protected] (Eduardo G. Carrano), [email protected] (Thomas J.R. Stidsen) Preprint submitted to European Journal of Operations Research March 11, 2017 cuts improved hugely the linear relaxation of the formulation, leading to an average gap reduction of 32%. Applied to XHSTT-2014 instance set, the alternative formulation provided four new best known lower bounds and, used in a matheuristic framework, improved eleven best known solutions. The computational experiments also show that the resulting integer programming models from the proposed formulation are more e ectively solved for most of the instances.