Jagtenberg sheds a different light on the decision process in order to determine which ambulance to send to which incident. Many researchers and practitioners use the ‘closest idle’ policy without questioning it, but this is not necessarily optimal. Jagtenberg’s research shows that an ambulance can be chosen, such that remaining idle vehicles remain a good position with respect to expected incidents in the near future. Jagtenberg: “Although we do not advise all EMS managers to immediately discard the closest idle dispatch method, we do show that the typical argument – that it would not lead to large improvements in the fraction of late arrivals – should be changed.”
Dynamic Ambulance Repositioning
Dynamic ambulance repositioning (proactively relocating idle vehicles in order to reduce response times) appears to improve the fraction of late arrivals compared to the scenario in which each vehicle always returns to its home base significantly. Not only the performance at the response time threshold is improved, but the whole distribution of response times is shifted to the left. The new method is intuitive and easy to implement, and also serves as a suitable base for extensions. Jagtenberg and colleagues demonstrated the practical relevance of this heuristic by implementing a decision support tool in EMS region Flevoland.
Jagtenberg also introduces several models to improve the fairness in ambulance logistics. Most models in ambulance planning maximize the number of people served, regardless of where they are living. This approach benefits people living in the cities, at the expense of people living in remote areas. Rather than simply maximizing the number of people served, she considers the distribution over the different areas where people live. To that end, ambulance optimization models from a social welfare perspective are applied.
Date: Tue, 28/02/2017 - 13:45 - 16:30
Location: Aula of the VU University, Boelelaan 1105 in Amsterdam
Promotors: prof.dr. R.D. van der Mei, prof.dr. S. Bhulai
Thesis: “Efficiency and Fairness in Ambulance Planning”