1. Comparing Aggregate Trip- Based and Disaggregate Tour-Based Travel Demand Models: Columbus Highway Results

2. Research Project Overview Research led by University of Texas-Austin with AECOM, John Bowman, Mark Bradley & Ram Pendyala Main objective: examine the performance of the trip-based and tour-based frameworks for Columbus in the context of a before-and-after project analysis

3. Major Tasks Update trip-based model to resolve differences in estimation datasets, TOD, geographic coverage and other areas Develop 1990, 2000 and 2005 scenarios (including socio-economic data, networks, traffic counts, etc.) Compare models’ regional-level results to Census (1990, 2000), Household Interview Survey (1999), ACS (2005) Decide on study projects Compare models’ project level-results

4. Brief Model Comparison Trip-Based ModelTour-Based Model Unit of TravelTripTour Travel AggregationZonal-levelPerson-level Estimation Datasets Generation Distribution Mode Choice 1999 HIS 1993 COTA On-Board 1999 HIS 1993 COTA On-Board + 1999 HIS Geographic Coverage 1877 zones across 7 counties Time-of-Day Fidelity Generation Distribution Mode Choice Assignment Daily Peak/off-peak 4 time periods 1-hour blocks 4 time periods Base Year(s)2000, 2005

5. Validation - VMT

6. Validation - % RMSE

7. Model-to-Model Comparisons Trip distance by trip purpose Delta volume bandwidth plots –∆ volume = Tour model – Trip model

8. Comparison of Trip Length by Purpose 8

9. Delta Volume Bandwidth Plot 1990 9

10. Delta Volume Bandwidth Plot 2000 10

11. Delta Volume Bandwidth Plot 2005 11

12. Regional-Level Results Vehicle ownership –Tour model performs better in Franklin County –Trip model performs better in other counties Work flows –Both models generally perform the same, except for inter-county movements where the tour model generally performs better Average work travel time –Both models generally perform the same

13. Findings from the Report Need to investigate why tour-based model systematically under- performs in vehicle ownership outside Franklin County Overall there are few major differences between the two models (slight overall edge to tour-based model?) It is difficult to make disaggregate model comparisons when the models have different units of travel –Translating units leads to inconsistencies at a disaggregate level, making the tour-based model’s full range of potential benefits difficult to compare to trip-based models More comparisons between trip- and tour-based models are needed to verify these findings

14. Project-Level Analysis Polaris – IR 71/ SR 750 Polaris Parkway –Large retail and employment growth –Interchange and other roadway improvements Rome-Hilliard – IR 70/IR 270 –Large land-use development –No roadway improvements Spring-Sandusky – downtown Columbus –No major land-use changes –Major roadway improvements Control area – IR 71 in southwest Columbus –No major land-use changes or roadway improvements

15. All Study Areas Spring-Sandusky Study Area Polaris Study Area Hilliard-Rome Study Area Control Area

16. Polaris - 1988

17. Polaris - 2008

18. Spring-Sandusky Study Area

19. 19

20. 20

21. Hilliard-Rome Study Area

22. 22

23. 23

24. Control Area

25. Volume to Counts Polaris – 1990 Red – Overassigned Blue - Underassigned Trip Tour

26. Volume to Counts Polaris – 2000 Red – Overassigned Blue - Underassigned Trip Tour

27. Volume to Counts Polaris – 2005 Red – Overassigned Blue - Underassigned Trip Tour

28. Volume to Counts SSI – 1990 Red – Overassigned Blue - Underassigned Trip Tour

29. Volume to Counts SSI – 2000 Red – Overassigned Blue - Underassigned Trip Tour

30. Volume to Counts SSI – 2005 Red – Overassigned Blue - Underassigned Trip Tour

31. Volume to Counts Rome Hilliard – 1990 Red – Overassigned Blue - Underassigned Trip Tour

32. Volume to Counts Rome Hilliard – 2000 Red – Overassigned Blue - Underassigned Trip Tour

33. Volume to Counts Rome Hilliard – 2005 Red – Overassigned Blue - Underassigned Trip Tour

34. Volume to Counts Control Area – 1990 Red – Overassigned Blue - Underassigned TripTour

35. Volume to Counts Control Area – 2000 Red – Overassigned Blue - Underassigned Trip Tour

36. Volume to Counts Control Area – 2005 Red – Overassigned Blue - Underassigned Trip Tour

37. Design Forecasts Add 1 more “model” –Fratared a matrix of 1s to the Trip Ends from the Tour model

38. Volume/Counts and Forecasts Polaris

39. Volume/Counts and Forecasts Spring-Sandusky Interchange

40. Volume/Counts and Forecasts Rome-Hilliard

41. Volume/Counts and Forecasts Control Area

42. Speed Comparison

43. Conclusions With an aggregate assignment, there isn’t much difference between the demand models for your run-of-the-mill project traffic forecasts. Biggest difference is in what questions your model can answer Develop a model that answers questions that are being asked in your region. –Use your crystal ball to determine what questions are likely to be asked over the next 20 years.

44. Contacts Greg Giaimo – ODOT – 614-752-5738 greg.giaimo@dot.state.oh.us Rebekah Anderson – ODOT – 614-752-5735 rebekah.anderson@dot.state.oh.us Zhuojun Jiang – MORPC – 614-233-4147 Chandra Bhat – UT at Austin bhat@mail.utexas.edu Dave Schmitt – AECOM David.Schmitt@aecom.com