The first generation of the AMBAG regional travel demand model was developed in the 1990's using MinUTP. The model did not have a detailed transportation network and lacked a sophisticated mode choice model. The model base year was 1990 and forecast year was 2020.
A fully integrated 4-step trip-based model was developed during the period from 2002-2004. This model was built using the TransCAD software platform and included detailed transportation and transit networks and a nested logit mode choice mode. The model was calibrated using 2000 California households travel survey results, screenline traffic count data and Highway Performance Monitoring System (HPMS) VMT data. Transit functionality was not developed due to lack of transit boarding data and other constraints. The model area was also expanded to include Santa Clara County. This model had a 2000 base year and a 2030 forecast horizon and was used for the development of AMBAG's 2005 Metropolitan Transportation Plan (MTP) among other local and DOT projects.
The most current version of the AMBAG regional travel demand model (updated in 2009-2010) was implemented in the TransCAD 5.0 software platform and moved to a 2005 base year and 2035 forecast horizon and included updates to the trip generation and trip distribution components.
The model update also included an updated mode choice model, added a transit assignment process and incorporated an Excel based '5D' post-processing tool to evaluate the impact of various smart growth, mixed land use strategies on vehicle trip and VMT reduction ('5Ds' stand for Density, Diversity, Design, Destination and Distance from Transit). This version of the model was used to develop AMBAG's 2010 MTP and was the subject of this peer review.
