Reports and Documents

The following documents complement the User’s Guide, which can be referred to for further information:

• SANDAG ABM2+ Service Bureau Enhancements Final Report (2022) - The Service Bureau at SANDAG runs model scenarios for alternatives analysis in support of Traffic Impact Studies and General/Community Plan Updates. The enhancements will allow member agencies to provide growth forecasts from general plans or data provided by developers and convert these forecasts to the socioeconomic data required by ABM2+.
• SANDAG Crossborder Model (CBM) Report (2022) - describes the updated crossborder model(CBM) built on a 2019 crossborder survey. The updated CBM is the first model, built on ActivitySim, in SANDAG's modeling suite designed for 2025 Regional Plan.
• SANDAG ABM2+ Traffic Assignment (2020) - describes the traffic assignment as implemented using the Emme Modeler Tool, the generalized cost to determine the shortest path, the vehicle delay function by roadway type, and the convergence criteria test.
• SANDAG ABM2+ Convergence Test (2020) - describes the work undertaken to understand the impact of convergence criteria on Activity Based Model (ABM2+) traffic assignment and performance.
• SANDAG ABM2+ Enhancements to support 2021 RTP (2020) - describes the work undertaken to enhance the San Diego Association of Governments (SANDAG) activity-based model functionality for application to the Five Big Moves planning effort. Describes the enhancements in terms of impacts on model structure, explanatory variables, and sensitivities. The document also describes the re-calibration of the model to represent existing TNC and e-scooter demand.
• SANDAG ABM2+ Sensitivity Testing Report (2020) - describes a series of sensitivity tests to demonstrate the effects of various inputs on vehicle miles traveled (VMT), mode share, trip length, and transit boardings using Activity Based Model (ABM2+). The work was performed in response to the Final Sustainable Communities Strategy Program and Evaluation Guidelines issued by the California Air Resources Board (CARB) and to examine the responsiveness of ABM2+ to potential SANDAG 2021 Regional Plan strategies.
• SANDAG Special Destination Calibration (2018) - This report describes the work performed to calibrate and validate special generators in the SANDAG activity-based model. Special generators refers to beaches, hospitals, major shopping centers, parks, casinos, and other key recreation sites.
• SANDAG ABM2 Model Update (2018) - describes changes and enhancements made to prepare a new model system ABM2. The travel model was updated based upon 2016/2017 household travel survey data and 2015 transit on-board survey data, and the base-year of the model was updated to 2016. The document describes model changes and enhancements completed , the data used to re-calibrate and validate the revised model, and the process and results of model calibration and validation.
• Cross Border Xpress (CBX) Model Report (2018) - describes the Cross Border Xpress (CBX) model. Cross Border Xpress is a bridge exclusively for Tijuana International Airport passengers who cross the border between United States and Mexico.
• SANDAG Travel Model in Emme User Guide (2018) - describes the model as implemented using the Emme modeling framework and components (assignment and demand modeling tools). Integrated with disaggregate demand model components (CT-RAMP family of AB models). The report also provides “how-to” instructions for master run model operation and the operation of the components implemented within the Emme framework.
• San Diego Regional Transportation Study Technical Appendix (2017) - describes the questionnaire used for the 2017 household travel survey (HTS) and the adjustments made to the data that was collected.
• San Diego Regional Transportation Study Technical Report (2017) - describes the household travel survey (HTS) data that was collected to update, improve, and maintain the SANDAG travel demand forecast models. The innovative methods used to produce the high-quality and higher-quantity dataset, when compared to similar previous studies in the region, is also explored.
• Pricing and Travel Time Reliability Improvements Report (2016) - describes the pricing and travel time reliability improvements that are fully integrated in ABM2 and ABM2+. This project was funded by a SHRP2 C04 grant.
• Activity-Based Model and Commercial Vehicle Model Validation Report (2016) - describes the goodness-of-fit of each model component to observed data for the base year (2008) and the process of adjusting parameters to better match observed data. Since then, the base year has been changed to 2010, to 2012, and to 2016 to reflect changes in 2010 Census and San Diego Forward, the new SANDAG RTP. Additional calibration and validation reports for base year 2010,2012, and 2016 are also available as additions to the 2008 calibration and validation report.
• Active Transportation Improvements Report (2015) - describes the bike and pedestrian modeling improvements that are fully integrated in ABM.
• Activity-Based Travel Model Estimation Report (2015) - describes the estimation results for each model component, with more details on the formulation of each model and the interpretation of the parameter values.
• Commercial Vehicle Model (CVM) Report (2014) - describes the tour-based commercial vehicle model that is integrated in ABM2 and ABM2+ as a special market model.
• External Heavy Duty Truck Model (2013) - describes the external heavy duty truck model that is integrated in ABM2 and ABM2+ as a special market model. This model is an aggregate model built on top of FHWA's Freight Analysis Framework data (FAF). The software has been converted from Java to Python in 2018. The data sources has been updated from FAF2 to FAF4 in 2018.
• Activity-Based Travel Model Specifications Report (2012) - describes the structure of the resident and special market models (with the exception of the heavy truck model), the mathematical form of each model component, and the variables considered.