Workforce scheduling with logical constraints: theory and applications in call centers

5 Concluding remarks and future prospects 55 Bibliography 57 Introduction Nowadays, enterprises and organizations are faced with increasing demand requirements. On the one hand, it means that they have to provide high quality of service for their customers. On the other hand, they would like to satisfy their employees' demand as much as possible. Thus, companies such as airlines, hospitals, police and ambulance departments, telephone companies and banks face a very delicate problem with workforce scheduling. Generally, workforce, labor or personnel scheduling or rostering is the process of designing work timetables for employees to satisfy the demand requirements for its services. Different kind of mathematical approaches have developed in order to help the companies to solve this problem. According to [6] the development of these mathematical models and algorithms involves the following levels: 1. a demand modeling study that collects and uses historical data to forecast demand for services and converts these to the staffing levels needed to satisfy service standards, 2. consideration of the solution techniques required for a personnel scheduling tool that satisfies the constraints arising from workplace regulations while best meeting a range of objectives including coverage of staff demand, minimum cost and maximum employee satisfaction, 3. specification of a reporting tool that displays solutions and provides performance reports. In this master thesis we focus on problems in the second level, i.e., the shift scheduling and the staff assignment problem. The general shift scheduling problem involves determining the number of employees to be assigned to each shift to satisfy the demand requirements. In the staff assignment problem we have the number of required employees for each shift and we have to assign employees for shifts. It is very important, but meanwhile very difficult to find an optimal solution that minimizes the cost and satisfies employee preferences of these complex and highly constrained problems. The main interest of this thesis is to introduce and apply a mathematical programming model, which can solve both the shift scheduling and the staff assignment problem. In this model we use logical constraints to model different conditions and requirements by