Three methods used to solve an examination timetable problem

Abstract

This paper describes the problem of examination timetables at the University of Technology of Compiègne and the solutions we devised. The problem we faced was drawing up a week-long the examination timetable, taking into account a number of different constraints. These constraints are administrative, physical and related to preferences. Three tools were developed to solve this practical problem. The first tool is an exact method based on a tree search, the second is based on the tabu technique, and the third is an interactive computer aided design system. The most effective is the tree search method, but the tabu search technique may be a convenient alternative for several reasons. The computer aided design system can be used if all the automatic techniques fail. In the first part of this paper we describe the problem. In the second part we present a model using a reduction of the problem and relaxed constraints. Next, the three methods are described, and we briefly present the related problem of the assignment of invigilators. The results we present in the fourth part show that there exists no solution which takes into account all the constraints. We have solved the related problem of invigilator assignment using the well known out-of-kilter method. Computational results are presented.