Field notes
Where should we count traffic?
A limited survey budget makes the choice of locations part of the analysis.
01
Start with the decision
Traffic counts help check and calibrate a transport model. Choosing locations only because they are convenient can leave parts of the network poorly represented. The count-location project starts with the structure of the network and the areas the survey needs to cover.
02
Find useful connections
The workflow scores links using betweenness centrality: how frequently shortest paths pass through a link. Paths use travel-time weights, with trip-distance constraints by road class. Eligibility rules identify suitable count locations; centrality describes network structure rather than observed traffic.
03
Keep the spatial balance
Selection happens within traffic analysis zones, so the result is spread across the metropolis. In this project, the configurable target is the top 20% of eligible metropolitan links by centrality in each zone. The interactive project maps show the selected links and their context.