Comparison of Fixed Targets Utilized by State Agencies and the Use of Varying Targets in the Calibration of Traffic Simulation Models




microsimulation, Traffic simulation, Traffic Modeling, Calibration guidelines, Calibration targets, Traffic Operation


Several state departments of transportation have developed simulation guidelines with a strong emphasis on model calibration. These guidelines generally specify fixed targets for each performance measure used in the calibration. However, only a few studies exist that explain the rationale behind and the justification for selecting these calibration targets. In 2019, the Federal Highway Administration (FHWA) released an update to its traffic simulation development methodology, with the concept of calibration targets that vary by segment, time period, and simulated operational scenario depending on the day-to-day variations in the calibrated measure values. As transportation agencies consider the possibility of adopting the FHWA calibration methodology, questions are being raised by the simulation community on how different are the values of the varying targets calculated using the FHWA methodology compared to the existing fixed targets that have been used in the industry for a long time. The purpose of this study is to compare the results from the use of varying calibration targets, as proposed in the methodology of the 2019 guidance, with the fixed targets in the state DOT guidance.


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