Model Calibration - Partial Automation

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Develop software to automatically run the model, compare select sub-model results to expected values, and intelligently automatically adjust alternative specific constants based on the differences. For example, run trip mode choice, summarize trips by mode, compare trips by mode to the surveyed trips by mode, and adjust the mode specific constants based on the log of the difference ratio * a dampening factor. Repeat the procedure until difference is minimized and respect min and max adjustment constraints. This has been done before for simpler trip-based models and could be done for ABMs. This feature needs to be used with caution and would require design related to how to specify tracked and expected outputs for each sub-model.

May also want to consider Automated Calibration Pilot. Calibrating an activity-based model is challenging, as the number of parameters is large and the observed data is often scarce. In Version 1.6, the Consortium will begin experimenting with automated calibration procedures via one or more pilot demonstrations. The Consortium expects to continue improving the automated calibration procedures in subsequent ActivitySim releases.