On-Time Reliability Impacts of Advanced Traveler Information Services (ATIS): Washington, DC Case Study

Internet-based Advanced Traveler Information Services (ATIS) provide the urban traveler with estimated travel times based on current roadway congestion. Survey research indicates that the vast majority of current ATIS users are satisfied consumers who feel they save time by utilizing these services on a regular basis. However, in numerous field experiments and simulation studies, ATIS users experience little or no actual reduction in their in-vehicle travel time. This report describes an innovative analytical method (the simulated yoked study), which applies dynamic programming techniques to archives of observed roadway congestion to quantify the impact of regular ATIS utilization by urban commuters. A simulated yoked study comprises efficient modeling of paired driving trials between travelers with or without ATIS, conducted across regional urban networks and over months or years of archived data. In-vehicle travel time, as well as on-time reliability measures, are tracked for each simulated yoked trial participant. Using results from a large-scale case study in the Washington, DC area we show that even though over time ATIS users realize only marginally reduced in-vehicle travel time, they do realize substantial time management benefits from improved on-time reliability and trip predictability.