Learning Abstract Scheduling Models

Abstract

In practice, most scheduling problems are an abstraction of the real problem being solved. For example, when you plan your day, you schedule the activities which are critical; that is you schedule the activities which are essential to the success of your day. So you may plan what time to leave the house to get to work, when to have meetings, how you share your vehicle with your spouse and so on. On the other hand, you probably do not consider the activities that are easy to arrange like brushing your teeth, going to the shops, making photocopies and other such tasks that can usually be accomplished whenever you have the time available. Often, if a schedule goes wrong, it is because a missed or underestimated activity had a signi.cant impact on the schedule. We typically learn which activities are critical by experience and create an abstract scheduling problem including only these critical activities. Instead of scheduling the non-critical activities we estimate their e.ects in the abstract scheduling problem.

This work has received support from Science Foundation Ireland under Grant 00/PI.1/C075, Irish Research Council for Science, Engineering, and Technology under Grant SC/2003/82, and ILOG, SA.