National Institute for Transportation and Communities

PRESENTATION ARCHIVE

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OVERVIEW

This webinar will demonstrate the tremendous value of GPS trajectory data in understanding statewide travel patterns and measuring performance. First, Dr. Markovic (U of Utah) will conduct visual exploration of GPS trajectories that capture about 3% of all the trips in Utah. He will briefly discuss the problem of scaling GPS trajectories to the population, and then focus on the use of scaled trajectories in computing origin-destination matrices, vehicle-hours delays, vehicle-miles traveled, and trip-based performance measures. Second, Dr. Franz (CATT Lab) will demonstrate a suite of visual analytics that enables transportation agencies to easily explore terabytes of GPS trajectory data. He will demonstrate different tools and share the experience of 5 state DOTs that are currently using CATT Lab's trajectory data suite.

KEY LEARNING OUTCOMES

• Trajectory data represents the most complete vehicle-probe data and provides unprecedented opportunity for transportation system analysis.
• Transportation agencies can easily leverage visual analytics to obtain insights in statewide traffic patterns and...

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This paper uses econometric techniques to examine the determinants of vehicle miles traveled (VMT) in a panel study using data from a cross section of 87 U.S. urban areas over the period 1982-2009. We use standard OLS regression as well as two-stage least squares techniques to examine the impact of factors such as population density, lane-miles per capita, per capita income, real fuel cost, transit mileage, and various industry mix variables on VMT. We use a distributed lag model to estimate the long run elasticity of various factors on VMT driven.

Preliminary empirical results show the demand for VMT in urban areas is positively and significantly impacted by lane miles, personal income, and the percent of employment in the construction. Fuel price, transit use and population density are all found to be negatively related to VMT per capita. Consistent with results from earlier studies, we find the long run price elasticity of demand for VMT per capita is approximately five times larger than the short run elasticity.

Holding all factors constant, per capita VMT is found to differ significantly by region with VMT being higher the more western and the larger the population size of an urban area. Finally, we find that the industry mix or the urban area also has a significant impact on driving.

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New FHWA VMT Forecasts and Implications for Local Planning

or

Post-Apocalyptic Zombies Ate Oregon’s Post-Recession, ATR Regression

Where: Room 204 of the Distance Learning Center Wing of the Urban Center at PSU

A summary of FHWA’s new national traffic trends assessment will be presented, including discussion of varied factors influencing forward-thinking forecasts. Examples of Oregon statewide vehicle miles travelled (VMT) and historic traffic trends from ATR stations in the Portland urban region and greater Willamette Valley will be highlighted. VMT, population and income data will be noted with implications on local transportation planning.

Andrew is an associate with David Evans & Associates, Inc., with over 28 years of experience in multimodal transportation planning with emphasis on sustainable community and Complete Street policy and plan development. He focuses on developing multimodal transportation plans with context-sensitive street standards and policies that implement enhanced bicycle and pedestrian use and circulation. His area of expertise includes measured pedestrian-access-to-transit connectivity, the implementation of...

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Topic: Airsage cell phone data and its application in travel modeling
Summary: As part of the initial phase of development for the Idaho Statewide Travel Demand Model, Parsons Brinckerhoff developed a base year auto and truck trip matrix using AirSage cell phone OD data, a statewide network in Cube, traffic counts, and origin-destination matrix estimation (ODME) procedures. To begin, the 4000+ statewide zone system was aggregated into a 700 super zone system for collecting the cell phone OD data. Next, the cell phone data was collected for the month of September 2013 for the following market segments: Average weekday resident HBW, HBO, NHB, and visitor NHB trips. The cell phone trips were then disaggregated to zones using each zone’s share of super zone population and employment. These initial trip matrices were assigned to the daily statewide network using free flow travel time for route impedance and iteratively adjusted to minimize the difference between the estimated link volumes and traffic counts by user class.

This iterative trip matrix balancing procedure, also known as ODME, converged nicely by user class and facility type and produced reasonable flows. The resulting trip matrix trip length frequencies matched fairly well with the...