Accuracy Standards for FSUTMS Transit Model Validation
Model validation is an important step in travel demand modeling. It serves to ensure that the results from calibrated models are consistent with those observed in the field. In the Florida Standard Urban Transportation Model Structure (FSUTMS) highway modeling arena, various consistency checks for the validation of the distribution and assignment models are suggested for highway network. They include:
- the comparison of the gravity model trip length outputs with those from the trip survey data from which the model was calibrated;
- the comparison of predicted link volumes with ground counts at screenlines, cordons, and/or cutlines; and
- the comparison between the derived statistics from the subject model with those from case studies of other areas with similar characteristics.
Statistics such as systemwide vehicle-mile-traveled (VMT), vehicle-hour-traveled (VHT), link volume by facility type, area type, facility size (in term of number of lanes), and volume group Root Mean Square Error (RMSE) are major criteria for validation. However, for transit modeling, little or no accuracy standards have been defined for validating transit assignments. The main objective of this project is to develop accuracy standards for validating transit assignment results. Specifically, this project will
- review literature related to validation of transit assignment,
- obtain and process APC and checker's data from select transit agencies, and
- develop accuracy standards for transit model validation.