Rota A research project on algorithms for workforce scheduling and shift design optimization 


Problems In project Rota, we consider the problem of the designing the shifts, and the problem of assigning employees to particular shifts or daysoff for rotating schedules. Both problems of shift design and assignment of employees to shifts and daysoff are NPcomplete. Design of shifts For the problem of shift design, we are given the workforce requirements for a certain period of time, constraints about the possible start and the length of shifts, and an upper limit for the average number of duties per week per employee. The aim is to generate solutions that contain shifts (and the number of employees per shift) that fulfill all hard constraints about the shifts, as well as minimize the number of shifts, over and understaffing, and differences in the average number of duties per week. (Download set of benchmark examples) Generation of workforce schedules After the shifts are generated, the assignment of employees to shifts or daysoff for a given period of time can be made. There are two main variants of workforce schedules: rotating (or cyclic) workforce schedules and noncyclic workforce schedules. In a rotating workforce schedule  at least during the planning stage  all employees have the same basic schedule but start with different offsets. Therefore, while the individual preferences of the employees cannot be taken into account, the aim is to find a schedule that on average is optimal for all employees. In noncyclic workforce schedules the individual preferences of the employees can be taken into consideration and the aim is to achieve schedules that fulfill the preferences of most employees. In both variations of workforce schedules other constraints such as the minimum number of employees required for each shift have to be met. In this project we consider the problem of rotating workforce schedules. For detailed description of both problems see publications. 
mailto: {musliu,wsi}@dbai.tuwien.ac.at 