Scheduling fixtures for New Zealand cricket

This paper describes the problem faced every year by New Zealand Cricket in scheduling the principal inter-regional fixtures. This is a combinatorial optimization problem with few constraints but many objectives, which are described in detail. A technique known as Subcost-Guided Simulated Annealing is used to solve this problem, producing one or more schedules of high quality. One particular feature of the problem requires great care – the determination of adequate neighbourhoods for such a tightly constrained problem, where most simple changes lead to infeasibility. The approach adopted is to use a complex and unorthodox definition of a perturbation, each one leading to several possible neighbouring solutions which are generated by means of a tree search procedure. The system will be used in practice for the 2003–2004 cricket season and beyond.