All explainers · Agent-based simulation, explained
The MATSim loop
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In one sentence
The converged state is what scenarios are compared in; calibration tunes the parameters so that it matches observation.
Why it matters
Every person keeps up to five plans. Each iteration one plan is executed on the network and timetable, scored, and in replanning either kept (85 %) or changed — a new route, shifted times, another mode for a subtour (5 % each). Over 400 iterations the plan memory fills, the worst plan is forgotten, and the average score flattens; for the last 20 % innovation is switched off.
Agent-based simulation is usually explained with equations or with a screenshot of a running model. Neither shows why a planner should care. These explainers show the mechanism itself — one person, one day, one score — so that the results on a dashboard stop being a black box.
Sources
- Scoring parameters are typical MATSim values (illustrative); see Horni, Nagel & Axhausen (2016), ch. 3
- Horni, A., Nagel, K. & Axhausen, K. W. (eds.) (2016): The Multi-Agent Transport Simulation MATSim. Ubiquity Press
What you see
- 00.0Plans → simulation → scoring → replanning
- 02.0Plan memory fills
- 06.0Average score rises
- 14.0Innovation off, last 20 %
- 17.0Converged
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