As the Crook Flies: selecting the best method for travel distance estimation

Mr Scott Davidson1, Mr Timothy Mashford1

1Victoria Police, Docklands, Australia


Intelligence analysts are often required to calculate distances between two locations, for example when examining travel patterns between criminals’ residences and their offence locations. Whilst GIS-based network routing tools provide the most accurate distance estimates, these can be expensive to acquire and complex to set up. Analysts instead often utilise more simplified methods for distance calculations, for example ‘as the crow flies’ straight lines. These methods, whilst easy to calculate, may not provide results which reflect real world travel distances, impacting on the reliability of insights gained from these analytical results. This paper compares several simplified distance calculation methods, to determine the best method(s) which should be applied when analysing distances for crime or road policing intelligence purposes.


Scott is a Geospatial Specialist with over 18 years’ experience in the GIS field. He has spent the last 12 of those working at Victoria Police in roles across intelligence and emergency management.