BRouter suspect manager: find suspicious nodes in the road network

The suspect manager is a tool to help you find errors and inconsistencies in the road network.

This is experts only. Suspects are really just suspects, most are not issues, the false-positive-rate is high!

See suspect_scanning_readme.txt for technical details on the rule-set and the suspect life-cycle.

Please update suspect status after review! To make status updates, you are required o to some test routings in BRouter-Web (1 to mark as confirmed, 4 to mark as false-positive). To do that, use the link "Open in BRouter-Web". Inside BRouter-Web, click on the Pen-Button ("draw route"), then click on the map to set the second waypoint. You can do more test routings by moving one of the 2 waypoints. After marking as confirmed, go on and mark as either "fixed" (if you actually fixed the issue) or use "hide for.." to hide the suspect for some time (if e.g. it's a construction or you wrote a note or a changeset-comment).

Suspect scanning is done via random routings with a variant of the car-eco profile. In these random routings, the graph is traversed from a random seed-point within a 30km-radius disc around that see-point. Fo each 1-degree by 1-degree square, the number of seed-points is calculated such that the area is covered 6 times on average. Half of these random routings are done in forward-logic, the other half backward. However, also with this 6-fold coverage, not every suspect is detected in every scan, because some detections depend on the logical direction, the routing direction, or seed-points hitting special routing half-islands.

If you open the detail page for a supects, it shows the "Triggers" that triggered the suspects to help you get an idea what could be wrong. Currently there are 9 different triggers (see suspect_scanning_readme.txt for a description):

dead-end, dead-start, node-block, bad-access, unknown access, sharp-exit, sharp-entry, sharp-link, bad-tr.

To use the "Open in JOSM (via remote control)" option JOSM must be listening for HTTP on port 8111.

Suspect scanning is done every morning, but there's a weekly rythm to help structure the work: the weekly run at Sunday morning is what is displayed as the default analysis and in the Osmoscope views, while the daily run is hidden behind a special link. The result of the weekly run is filtered by subsequent daily runs, so suspects disappear from the result of the weekly run if they are not re-detected in the daily run. The Osmoscope views are limited to strongly filtered views, so you can not see all open suspects, but e.g. the new ones. The BRouter data-refresh run starts every night (with map snapshot time 1 AM) an finishes in the morning. After that, the suspect scan takes another 2 hours, so new suspects ae available at some time before noon. In addition, there's also a "strict" scan where some rules are stricter (especially with respect to destination access) so that the strict scan find's some more suspects. Here's an overview on the relavant links:

  • https://brouter.de/brouter/suspects The standard, weekly, analysis, refreshed sunday morning
  • http://brouter.de/osmoscope Osmoscope view on the standard analysis
  • https://brouter.de/brouter/suspects/daily The daily scan, refreshed every morning except sunday
  • https://brouter.de/brouter/suspects/strict The strict scan, with some more suspects around destination access

    You can work on "new" suspects that first showed up in the latest weekly scan, or on "all" suspects. If you plan to start tracking suspects for a country or region with no previous suspect tracking done, it's best to start with new "new" suspects, as they have a lower false-positive rate and your chances are better to contact the mappers that created the bad changesets. Cleaning up "all" suspects for a big country is a bigger projects that needs many weeks.


    ( Privacy Policy )