TREC research addresses complex transportation problems by drawing on multiple disciplines, including engineering, planning, economics and design, from across the Portland State University campus. Use the search box at right to search for a specific project.

Research Highlights

Unsupervised Approach to Investigate Urban Traffic Crashes Based on Crash Unit, Crash Severity, and Manner of Collision

Farzin Maniei Stephen Mattingly
Both crash frequency analysis (CFA) and real-time crash prediction models (RTCPMs) typically divide a highway into segments with a constant length for data aggregation. Despite the significant impact of the segment length in several previous traffic safety studies, no standard approach exists for determining a recommended segment length for crash data aggregation. This research investigates the impact of fragment size (segment length) on traffic crash data aggregation and establishes a… Read More

Evaluating Efforts to Improve the Equity of Bike Share Systems

Nathan McNeil John MacArthur , Jennifer Dill , Joe Broach
BREAKING BARRIERS TO BIKE SHARE: Insights on Equity. Public bike share systems have rapidly expanded across the United States in recent years. However, there is evidence that significant portions of the population are underrepresented among bike share users, including people of color, along with lower-income, female, older adults and less-educated groups. Lack of bike share stations in neighborhoods with people of color and/or lower incomes is one factor, but does not completely explain the… Read More