A Tiered Approach to Validating the Integrated Florida Statewide Model

The Florida Department of Transportation (FDOT) began developing a statewide travel forecasting model in the 1980s. The current model is integrated to simulate interactions between passenger vehicles and freight trucks. The Integrated Florida Statewide Model uses a 4000-zone structure. The transportation network includes MPO model network links and major rural roadways. Intermodal terminals, major seaports and rail yards are identified. The National Highway Planning Network is used to assign truck trips from outside Florida. This paper focuses on validation processes used for the base year 2000 Florida Statewide Model. In response to production needs dictated by legislative directives, validation was divided into three phases: systemwide, districtwide, and corridor-level. Systemwide validation focused on achieving reasonable results on a statewide basis and providing an operational model for use in preliminary corridor study analyses in conjunction with available urban and regional models. The districtwide validation phase emphasizes improved model validity for each of FDOT's seven geographic districts and includes adjustment of parameters specific to each of these regions. Statistical comparisons are made against district regional models and the resulting validation will enhance the simulation of cross district travel movements. Finally, the corridor-level validation is most like an urban area model validation with a focus on a set of specific proposed statewide corridors with more stringent accuracy checks on the surrounding network and zonal data to improve model accuracy. This tiered approach to model validation allows for timely delivery of product for agency use, with a continued focus on model refinement.