Retractable contract network for empowerment in workforce scheduling

This paper is about business modelling and negotiation protocol design in distributed scheduling, where individual agents have individual (potentially conflicting) interests. It is motivated by BT's workforce scheduling problem, in which multiple service providers have to serve multiple service buyers. The service providers and buyers all attempt to maximize their own utility. The overall problem is a multi-objective optimization problem; for example, one has to maximize completion rates and service quality and minimize travelling distances. Although the work is motivated by BT's business operations, the aim is to develop a general negotiation protocol for staff empowerment. Standard contract net is a practical strategy in distributed scheduling where agents may have conflicting objectives. In this paper, we have introduced a retractable contract net protocol, RECONNET, which supports hill-climbing in the space of schedules. It is built upon a job-release and compensation mechanism. A system based on RECONNET has been implemented for BT's workforce scheduling problem. The software, which we call ASMCR, allows the management to exert full control over the company's multiple objectives. The manager generates a Pareto set of solutions by defining, for each buyer and seller, the weights given to each objective. ASMCR gives service buyers and sellers ownership of their problem and freedom to maximize their performance under the criteria defined by the management. ASMCR was tested on real-sized problems and demonstrated to meet BT's operational time requirement. It has full potential to be further developed for tackling BT's workforce scheduling problem.