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
Using Time-Series Analysis to Precisely Identify and Rank Road Hotspots
Alexander Lee Wei Lin
Over the past decades, many ranking methods have been proposed. However, results vary from method to method, and one of the issues behind ranking is the element of subjectivity. One approach to resolve these issues is the use of combined models. One of the combined models is the Enhanced Empirical Bayesian (EB) method that incorporates the use of the similarity measure based on the Proportion Discordance Ratio (PDR). This model is developed to assess and objectively quantify similarity among…
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Multimodal Trip Generation, Vehicle Ownership and Use: Characterizing The Travel Patterns of Residents of Multifamily Housing
Kelly Clifton
Many cities are reconsidering their reliance on ITE’s Trip Generation Manual, now in its 10th edition. Kelly Clifton and co-investigator Kristina Currans of the University of Arizona examine the advantages and limitations of ITE’s land use taxonomy for multifamily residences. They find that the land use categories aiming to capture intensity of development for residential land uses (high-rise apartments, for example) do not appear to capture any more variation in the vehicle or person trip…
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