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…
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The use and influence of health indicators in transportation decision-making
Kelly Rodgers
As a social determinant of health, transportation significantly contributes to well-being through several pathways. Researchers and practitioners have called for health indicators as one way to integrate public health concerns into transportation decision-making. However, it is unclear how indicators are used and what their impact is on policy. This case study of five cities explored how health-related indicators are being used in municipal transportation plans, whether they are…
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