Author: Bridget Scheyd RobicheauxPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Analysis of Data Selection and Inclusion for Highway Safety Manual Model Calibration
Author: Bridget Scheyd RobicheauxPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Calibration of Highway Safety Manual Prediction Models for Freeway Segments, Speed-change Lanes, Ramp Segments, and Crossroad Ramp Terminals in Kansas
Author: Imalka Chiranthi MataragePublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Crash prediction models in the Highway Safety Manual (HSM) are used to quantify the safety experience of existing and new roadways. Safety performance functions (SPFs) or crash prediction models are statistical formulas developed on limited data from a few selected states, Kansas not being one of those states. Therefore, the HSM recommends calibration of HSM-default SPFs, or development of local SPFs, to enhance accuracy of predicted crash frequency. This dissertation demonstrates the HSM calibration procedure and its' quality assessment for freeway segments, speed-change lanes, ramp segments, and crossroad ramp terminals in Kansas. The study used three years of recent crash data, the most recent geometric data, and HSM-recommended sample sizes for all facilities considered for the calibration. The HSM methodology overpredicted all fatal and injury (FI) crashes and underpredicted all property damage only (PDO) crashes for freeway segments. The HSM methodology consistently underpredicted both FI and PDO crashes for both entrance- and exit-related speed-change lanes. The HSM methodology overpredicted all FI crashes, underpredicted multiple vehicle PDO crashes, and overpredicted single vehicle PDO crashes for entrance ramp segments. In the case of exit ramp segments, the HSM methodology underpredicted all multiple vehicle crashes and overpredicted all single vehicle crashes. The HSM methodology overpredicted all FI crashes and underpredicted all PDO crashes for both signal- and stop-controlled crossroad ramp terminals. Cumulative residual plots and coefficient of variation were used to evaluate the quality of calibrated HSM-default SPFs. Results of calibration quality assessment indicated that estimated calibration factors were satisfactory for all freeway and ramp facilities considered in this study. However, for further accuracy and comparison purposes, calibration functions were developed to improve the fit to local data. Calibration functions were better fitted compared to calibrated HSM-default SPFs for freeway and ramp facilities in Kansas. Challenges faced, how those challenges were addressed, and data collection techniques used in this study are discussed. In summary, estimated calibration factors and developed calibration functions of this study would greatly improve making accurate decisions related to freeway and ramp safety in Kansas.
Roadside Design Guide
Author: American Association of State Highway and Transportation Officials. Task Force for Roadside SafetyPublisher:
ISBN:
Category : Roads
Languages : en
Pages : 560
Book Description
Updated and Regional Calibration Factors for Highway Safety Manual Crash Prediction Models (2016-2019)
Author: Taha SaleemPublisher:
ISBN:
Category : Traffic accidents
Languages : en
Pages : 59
Book Description
Regression Analysis of Count Data
Author: Adrian Colin CameronPublisher: Cambridge University Press
ISBN: 1107014166
Category : Business & Economics
Languages : en
Pages : 597
Book Description
This book provides the most comprehensive and up-to-date account of regression methods to explain the frequency of events.
Macro-Level Analysis of Safety Planning and Crash Prediction Models
Author: Publisher:
ISBN: 9780309705721
Category : Traffic accidents
Languages : en
Pages : 0
Book Description
The Highway Safety Manual (HSM) is a tool that helps transportation agencies make data-driven decisions about safety. It includes methods for quantifying safety performance and predicting crash frequencies. The HSM is currently being updated to include macro-level crash prediction models, which can be used to assess safety trends at a regional or national level. NCHRP Web-Only Document 348: Macro-Level Analysis of Safety Planning and Crash Prediction Models: A Guide, from TRB's National Cooperative Highway Research Program, provides guidance on how to use a spreadsheet tool developed during this project. The document is supplemental to NCHRP Research Report 1044: Development and Application of Quantitative Macro-Level Safety Prediction Models.
Roundabouts
Author: Lee August RodegerdtsPublisher: Transportation Research Board
ISBN: 0309155118
Category : Technology & Engineering
Languages : en
Pages : 407
Book Description
TRB's National Cooperative Highway Research Program (NCHRP) Report 672: Roundabouts: An Informational Guide - Second Edition explores the planning, design, construction, maintenance, and operation of roundabouts. The report also addresses issues that may be useful in helping to explain the trade-offs associated with roundabouts. This report updates the U.S. Federal Highway Administration's Roundabouts: An Informational Guide, based on experience gained in the United States since that guide was published in 2000.
The Art of Regression Modeling in Road Safety
Author: Ezra HauerPublisher: Springer
ISBN: 9783319354460
Category : Technology & Engineering
Languages : en
Pages : 0
Book Description
This unique book explains how to fashion useful regression models from commonly available data to erect models essential for evidence-based road safety management and research. Composed from techniques and best practices presented over many years of lectures and workshops, The Art of Regression Modeling in Road Safety illustrates that fruitful modeling cannot be done without substantive knowledge about the modeled phenomenon. Class-tested in courses and workshops across North America, the book is ideal for professionals, researchers, university professors, and graduate students with an interest in, or responsibilities related to, road safety. This book also: · Presents for the first time a powerful analytical tool for road safety researchers and practitioners · Includes problems and solutions in each chapter as well as data and spreadsheets for running models and PowerPoint presentation slides · Features pedagogy well-suited for graduate courses and workshops including problems, solutions, and PowerPoint presentations · Equips readers to perform all analyses on a spreadsheet without requiring mastery of complex and costly software · Emphasizes understanding without esoteric mathematics · Makes assumptions visible and explains their role and consequences
Statistical Methods in Highway Safety Analysis
Author: Bhagwant Naraine PersaudPublisher:
ISBN:
Category : Transportation
Languages : en
Pages : 88
Book Description
TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 295: Statistical Methods in Highway Safety Analysis focus on the type of safety analysis required to support traditional engineering functions, such as the identification of hazardous locations and the development and evaluation of countermeasures. Analyses related specifically to driver and vehicle safety are not covered, but some statistical methods used in these areas are of relevance and are summarized where appropriate.
Author: