Good afternoon everyone,
I'm calibrating an only cars and highways SUMO model. The only modifications done are in terms of connections, number of lanes and geometry of edges, everything else is default from osmWebWizard.
I use loop detector traffic and speed counts and run an algorithm that follows an iterative process:
- Build routes with flowrouter + implausibleRoutes + flowrouter with the implausibleRoutes restrictions, taking into account real traffic counts.
- Simulate and compare real vs simulated edge speeds (e1Detector)
- Compute a factor between vreal and vsimulated
- Modify parameter 'speed' on detector edges, then propagate to neighbors
- Optionally, if specified by the user, the algorithm runs a grid-search on global driver parameters (tau, sigma, speedFactor, speedDev)
Given the simplification of the model:
My questions:
- Is it methodologically acceptable to calibrate by modifying edge speed (interpreted as “effective” free-flow speed), or is this discouraged in SUMO?
- Is it better to keep speed limits fixed and calibrate only driver parameters?
- Any known pitfalls of adjusting speed this way for later use of the network?
Any short guidance or pointers to examples / best practices would be very helpful.
Thanks in advance,
Gabriel
