Multi-Criteria Ambulance Location Problem: better to treat some fast, or more in time?

For the location optimization of several ambulance stations, we outline a multi-criteria integer program to maximize the reached population within different time bounds. This technique is based on a realistic driving time estimation for ambulances on a detailed road network. The results show that, depending on which time bound is more valued, ambulance stations are more likely to be located in urban areas or evenly distributed across the study region. We used this model for real-world studies in Southwest Germany, where several ambulance station locations were optimized simultaneously.