Vehicle Probe Data Primer

The Vehicle Probe Data Primer includes the following sections:

1. Data availability – Vehicle probe data vendors offer numeric and visualization products for speed, origin-destination, and vehicle trajectory. Real-time, minute-by-minute, speed and travel time data are available along with historic average speeds for freeway and arterial road segments.
2. Data use – There are a variety of vehicle probe data uses, including real-time monitoring of traffic, winter weather operations, traffic incident detection, back of queue detection, and evacuation and event management. Agencies use archived data for a variety of critical transportation agency functions, including performance management, planning, investment and programming decisions, and research.
3. Data management – Vehicle probe data and other emerging data sources create new data management challenges for transportation agencies. To handle the enormous amount of data produced from these technologies requires agencies to transition from traditional to more modern, flexible, and scalable data management practices.
4. Data quality – One of the most common concerns transportation agencies have with the use of vehicle probe data is the quality of the data. Each vehicle probe data vendor has its proprietary approach to collecting, managing, and processing the data, making data source and integration a black box. Agencies have addressed this challenge by performing data quality and validity assessments to evaluate the quality of the data, mainly as it relates to travel speed and time.
5. Data integration – Integrating vehicle probe data with other programmatic and enterprise data provides an opportunity to enhance operations and decision-making by using both real-time and archived data; however, integrating vehicle probe data is one of the most significant deterrents to its use by state DOTs 1 . To be useful, probe vehicle data must be conflated temporally and spatially to a roadway network, which can be a challenge.
6. Agency vehicle probe data applications – This section presents vehicle probe data applications from four agencies, including Indiana DOT, Colorado DOT, Tennessee DOT, and the District of Columbia DOT.
7. Future of vehicle probe data – Vehicle probe data will become available at greater geographic fidelity and data quality as vendors ingest greater volumes of data from connected vehicles. The evolution of vehicle probe data means continued integration of new data sources (e.g., connected vehicle data) and the provision of analytics services for greater precision and accuracy of speed, trip, and path data.

• 1Pack, Michael L.; Nikola Ivanov; MLP LLC. NCHRP Synthesis 561: Use of Probe and Cellular GPS Data by State Departments of Transportation; Transportation Research Board, 2021.