Pia Mareike Steenweg: Optimal annual vacation scheduling for emergency medical services considering preferences and recovery


Annual vacation scheduling is usually based on satisfying employee preferences; however, it also has to meet organizational requirements at the same time. Typical preferences depend on the employee’s background and are bound to a specific day or a specified duration in a particular month, e.g. a week in May. In order to cope with difficult and unpopular working conditions in emergency medical services, the employees have to recover properly with their entitled vacation days. Former research has focused on dealing with conflicting preferences. However, it is neglected that parts of these conflicts only occur due to the necessity that employees declare explicit preferences to be met. In reality, these conflicts can often be solved as some employees are flexible regarding some preferences and willing to deviate from their preferences to some extent. Therefore, in this paper, an alternative approach is developed that allows employees who are more flexible with regard to their vacations to express fewer or less specific preferences and to satisfy them, nevertheless, in other ways for the remaining leave entitlement. The present contribution aims at the fulfillment of preferences as well as the advantageous allocation of vacation days to maximize recovery of employees in a mixed-integer optimization program. Those two objectives are considered and their importance can be specified individually per employee. In a case study, an optimal annual vacation schedule is generated for a large emergency medical services provider. The suitability of the approach is demonstrated in comparison with their manually generated schedule used in 2019.