Denver Regional Council of Governments Focus Activity-Based Travel Model

1. Denver Regional Council of Governments Focus Activity-Based Travel Model Triangle Regional Model Peer Review Suzanne Childress 11/2011

2. Focus Travel model • Tour-Based Model developed similar to Sacramento and San Francisco models • Called Focus because you get to bring details into focus (some of them are kind of ugly  ) • Includes walk and bike modes • Models Trips from X,Y coordinate to X,Y coordinate (point to point) • 2832 zones for assignment • Current population 2.9 million 2035 Forecast population around 4 million

3. Policy Tool (Why?) • Built to answer policy questions like transit oriented development, biking, walking • Also built to have greater sensitivity to input variables such as response to an aging population It has succeeded on both these fronts: Has been used for transit-oriented development and bike/pedestrian project evaluation Has been used for Regional Transportation Plan (RTP) runs twice

4. Example Sensitivity

5. Example Output:VMT per Person

6. Example Output: Walk Mode Share

7. Computing (Why not?) • Single Iteration Run Time: approximately 20 hours on a : • 32 processor server; 64 GB Ram; 64-bit; 400 GB Hard Drive • Have an additional 3 TB Storage Drive for storage only • Full speed feedback 3 days • One model run with all files included (mainly matrices) is about 60 GB • The code has a lot of room for optimization • Programmed in C# and GISDK, multi-threaded • Uses a SQL-Server database platform

8. Model Status • We’re getting the model ready for FTA New Starts and wider community roll-out. • Model has not been run outside of DRCOG at full scale: Major issue: computing requirements Major issue: we’re not updating our trip-based model • We are building an UrbanSim land use model now. • University of Arizona is building a Dynus-T model for us now.

9. Model Status • Will be in continuous improvement mode (as we were with trip-based model) -commercial vehicle modeling -currently improving modeling drive to transit egress -working on value of time and number of paths built by value of time -examining observed highway speeds compared to modeled; considering changes to free flow time -working on toll assignment

10. External, Commerical, and Airport Modeling • Relies on the trip-based platform. • Still have to run regular trip generation, distribution, mode choice for these trips. • Requires merging of trip-based and tour-based model results at the end.

11. Focus Model Flow: Stage 1 FEEDBACK

12. Focus Model Flow: 28 Steps Outside The Speed Feedback Loop: Run Once- STAGE 1 GISDK called from C#: GISDK Preprocess Java: 3. Population Synthesizer C# 4. PopSyn Output Processor 5. Size Sum Variable Calculator STAGE 2 GISDK called from C#: For DIA, I-E, E-E and Commercial Trips 1. DRCOG Multi-Period Highway Preprocess 2. DRCOG Multi-Period Transit Preprocess 3. DRCOG Transit Preprocess 4. Trip Generation 5. Highway and Transit Skimming 6. Trip Distribution 7. Mode Choice STAGE 3 C# Regular Trips 8. Regular Work Location Choice 19 . Tour Main Mode Choice 9. Regular School Location Choice 20. Tour Time of Day Choice 10. Auto Availability 21. Intermediate Stop Generation 11. Aggregate Logsum Generation 22. Trip Time of Day Simulation 12.Daily Activity Pattern 23. Trip Time Copier 13. Exact Number of Tours 24. Intermediate Stop Location 14.Work Tour Destination Type 25. Trip Mode Choice 15.Work-Based Subtour Generation 26. Trip Time of Day Choice 16. Tour Time of Day Simulation 27. Write Trips to TransCAD 17. Tour Primary Destination Choice 18. Tour Priority Assignment STAGE 4 GISDK called from C#: 28. Highway and Transit Assignment

13. For More Information More info: http://www.drcog.org/index.cfm?page=FocusTechnicalResources

14. Data (Maybe a why or a why not?) • Why: the model SHOULD be based on good, detailed data in the first place • Why not: time, money, and complicated management • Household Survey once every ten years • Initial Model: Used EXCEL energy data from building electrical hook-ups for point level data • Initial data collection took about one year in total: reached across agency • Now: we are developing a clean dataset of all buildings in the region for use in the travel and land use models: A major undertaking with several interns

15. Data Collection and Management • Had a big spreadsheet of data items assigned to people with a list of locations of the data and dates needed • Data is in continuous need for update and cleaning • Computing set up: One big storage drive (3 TB), One server for operations

16. Data Collection and Management • At DRCOG, we are always trying to integrate and centralize our data. It works to some degree but it’s truly a struggle. • GIS team has a database of all commonly used layers; travel model data is often derived from this and other data • Ideally, there would be a regional data catalog

17. Place Data

18. Data Stored in SQL Server

19. Managerial Details • DRCOG’s team: 1 Modeling Manager, 2 Senior Modelers, 2 Junior Modelers (budget including everything about 650K/yr) • 2 Land Use Economists • Substantial assistance from IT, GIS, and planning in development and application • When developing Focus, the senior modelers were devoted about 80% of the time to development, 20% to application issues; the junior modelers were 20% to development, 80% to application. • Requirements for modelers at DRCOG: programming skills, math through Calculus

20. Division of Labor • Developed about 50% in-house and 50% by Cambridge Systematics, Mark Bradley, John Bowman, and Parsons • Three models estimated in-house: regular work location, school location, and auto ownership • Code base for logit models written in-house Database structure developed in-house; database entirely filled in-house; All Models calibrated in house

21. Consultant Costs and Responsibilities • Approximately $1.25 million total development cost for Focus (excluding in-house costs) • Designed model structure • Estimated most models • Churned out code when design was in place with on-going assistance from DRCOG staff on the modeling side and database side

22. New Model Survey Costs • Total approximately: $1.2 million for Denver only or about $120,000 per year, over ten year period • New Travel Survey Completed in 2010- of the entire Front Range including Denver, Fort Collins, Pueblo, and Colorado Springs 12,000 Household Surveys 400 GPS Cordon Survey Commercial Total cost: $2.3 million Household Part is complete. Still cleaning and working on expansion weights.

23. Project Timeline • Winter 2006 – Summer 2010 • 2006: data gathering, model theoretical design • 2007-2008: model estimation, code and database framework creation • 2008-2010: code writing and implementation once basic design was in place, component completed about a rate of one per two- weeks.

24. Model Development Hard to Easy • Hardest: Writing our own code base in-house • Medium: Compiling needed data • Easier: Estimating models

25. Lessons Learned • Would definitely do this again. There’s just so much more room to improve behavioral realism. It’s more fun! • Estimate and calibrate as many models as possible to retain in-house knowledge • Use a database structure behind your model inputs and outputs for easy input and output creation • Don’t write your own model code from scratch. Use someone else’s. • Sufficient documentation and organization is essential and difficult.

26. Lessons Learned • If you are going to build a new next generation land use model, built it first. (It feeds the travel model). • Transition period will occur between models. • You will need a big storage drive – sooner rather than later.

27. Questions before recommendation • What are the math and programming skills of the modeling team? • Could the agency tolerate higher costs and longer run times in return for more outputs?