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Mixed Multinomial Logit Analysis Of Bicyclist Injury Severity In Single Motor Vehicle Crashes Based On Intersection And Non Intersection Locations
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Book Synopsis Mixed Multinomial Logit Analysis of Bicyclist Injury-severity in Single Motor Vehicle Crashes Based on Intersection and Non Intersection Locations by : Darren N. Moore
Download or read book Mixed Multinomial Logit Analysis of Bicyclist Injury-severity in Single Motor Vehicle Crashes Based on Intersection and Non Intersection Locations written by Darren N. Moore and published by . This book was released on 2009 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Standard multinomial (MNL) and mixed multinomial logit (MMNL) models are used to estimate the degree of influence bicyclist, driver, motor vehicle, crash geometry, roadway geometry and environmental characteristics have on bicyclist injury-severity, classified as property damage only, possible, non-incapacitating or severe. This study is based on 10,579 crash observations in the State of Ohio from 2002-2008. A log-likelihood ratio test is used to divide the bicycle/motor vehicle crashes into intersection and non-intersection location crashes. These models are used as base models for intersection and non-intersection MMNL models. Many variables are significant in both intersection and non-intersection location models. But six variables influenced bicyclist injury-severity at intersection locations but not non-intersection locations. Four variables influenced bicyclist injury-severity at non-intersection locations but not intersection locations. Some interesting finding are at intersection locations, the likelihood for a severe bicyclist injury increases by 31% if the bicyclist is not wearing a helmet, 99% if the motorist is under the influence of alcohol, 144% if the motor vehicle is a van, 59% if the motor vehicle front strikes the side of the bicycle, and 337% if the crash occurs on a horizontal curve with a grade. Non-intersection locations show the likelihood for a severe bicyclist injury increases by 608% if the bicyclist is under the influence of drugs, 194% if the motorist is under the influence of alcohol, 91% if the motor vehicle front strikes the side of the bicycle and 122% if motor vehicle is a heavy-duty truck."--Abstract.
Book Synopsis Analysis of Factors Affecting Crash Severity of Pedestrian and Bicycle Crashes Involving Vehicles at Intersections by : Abdulaziz Hebni Alshehri
Download or read book Analysis of Factors Affecting Crash Severity of Pedestrian and Bicycle Crashes Involving Vehicles at Intersections written by Abdulaziz Hebni Alshehri and published by . This book was released on 2017 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vulnerable road users (VRUs) such as pedestrians and bicyclists, also known as non-motorists, are vulnerable due to lack of protection in traffic. They are even more vulnerable at intersections due to increased exposure and conflicts with motor vehicles whose paths have to cross each other. The main objective of this thesis study was to determine factors that contribute significantly to the crash severity of intersection-related crashes involving motor vehicles and the vulnerable road users. When a motor vehicle crashes with a non-motorist road user, the non-motorist road user sustains the higher injury levels. Based on the objectives of this study, a three-year crash database from January 2013 to December 2015 acquired from the Ohio Department of Public Safety was utilized for this analysis. The logistic stepwise selection procedure was applied to estimate statistically significant predictor variables that contribute to increasing bicyclist and pedestrian-related crash severity levels. The logistic regression model identified five statistically significant predictor variables out of fourteen independent variables considered in the current research. The predictors that increase the crash severity of crashes involving VRUs who collide with vehicles at intersections are pedestrian-related, road contour, gender, light condition, and unit in error. The other factors that are usually significant such as posted speed limits, alcohol-related, gender, age, etc., were not significant in the current study. However, speed-related was not tested in the current study due to lack of enough cases where speeding was reported as contributing factor in the data set used.
Book Synopsis Safety Data, Analysis, and Evaluation by :
Download or read book Safety Data, Analysis, and Evaluation written by and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "TRB?s Transportation Research Record: Journal of the Transportation Research Board, No. 2514, explores 19 papers related to safety data, analysis, and evaluation in the transportation sector, including: Exploring Driver Error at Intersections: Key Contributors and Solutions; Level of Service of Safety Revisited; Longitudinal Analysis of Rural Interstate Fatalities in Relation to Speed Limit Policies; Predicting Crashes on Expressway Ramps with Real-Time Traffic and Weather Data; Multilevel Logistic Regression Modeling for Crash Mapping in Metropolitan Areas; Simulated Traffic Conflicts: Do They Accurately Represent Field-Measured Conflicts?; Assessing Safety Improvements to Pedestrian Crossings Using Automated Conflict Analysis; Understanding Factors Affecting Frequency of Traffic Conflicts Between Electric Bicycles and Motorized Vehicles at Signalized Intersections; Comparative Analysis of Injury Severity Resulting from Pedestrian?Motor Vehicle and Bicycle?Motor Vehicle Crashes on Roadways in Alabama; Validation of Crash Modification Factors Derived from Cross-Sectional Studies with Regression Models; Fault Determination for Crashes in Vermont: Implications of Distance from Home; Crash Patterns at Signalized Intersections; Analyses of Multiyear Statewide Secondary Crash Data and Automatic Crash Report Reviewing; Assessment of Pedestrian Risk at Crossings with Kinematic?Probabilistic Model; Predicting Driver Injury Severity in Single-Vehicle and Two-Vehicle Crashes with Boosted Regression Trees; Effects of Geodemographic Profiles of Drivers on Their Injury Severity from Traffic Crashes Using Multilevel Mixed-Effects Ordered Logit Model; Copula-Based Joint Model of Injury Severity and Vehicle Damage in Two-Vehicle Crashes; Identifying Optimal High-Risk Driver Segments for Safety Messaging: Geodemographic Modeling Approach; Evaluation of Signalized-Intersection Crash Screening Methods Based on Distance from Intersection."--Publisher's description.
Book Synopsis Analysis of Shared Micromobility Related Crashes by : Enock Mwambeleko
Download or read book Analysis of Shared Micromobility Related Crashes written by Enock Mwambeleko and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: United States cities have adopted shared micromobility systems to mitigate problems facing the transportation industry. The State of Florida has at least 13 established shared micromobility systems. Identifying the factors influencing the injury severity is critical for improving the safe operations of micromobility devices. This study investigates the leading factors affecting the injury severity for micromobility related crashes in Florida. The study investigates 463 crashes involving e-scooters or e-bikes between 2018 and 2022 in Florida, extracted by the Text-Mining approach from the SignalFour Analytics database. Analyses consisted of exploratory data analysis to discover trends and patterns. First, using the Pedestrian and Bicycle Crash Analysis Tool (PBCAT) to assess the crash types based on the motorist and non-motorist maneuvers. It then presents the descriptive analysis of the explanatory factors. The relationship between crash severity and other explanatory factors was modeled using Ordered Logistic Regression (OLR) to identify the significant factors. Then the Bayesian Network (BN) model was used to determine the interdependency between the variables. PBCAT results concluded that e-scooters riders are more vulnerable when crossing the intersection from the right-hand side of the motorist. At the same time, for e-bikes, most crashes occur on the travel/bike lane when the rider is traveling parallel to the vehicle. OLR suggested the shoulder type, AADT, driver's action, sidewalk width, NM age, gender and maneuver, time of the day, crash location and the type of control device as the most significant factors affecting the severity of micromobility crashes. Finally, The BN model result suggests the highest likelihood of fatal/severe injury is associated with the non-motorist (NM) crossing the signal-controlled intersection with the driver failing to yield the right of way. In roadway segment crashes, the highest likelihood is when the motorist is moving straight on a roadway with three or more lanes with curbed shoulders. Finally, the study suggests recommendations to mitigate the injury severity of micromobility crashes.
Book Synopsis Analysis of Risk Factors Associated with Fatal Intersection Crashes Involving Older Drivers in the Midwest by : Abdulaziz Hebni Alshehri
Download or read book Analysis of Risk Factors Associated with Fatal Intersection Crashes Involving Older Drivers in the Midwest written by Abdulaziz Hebni Alshehri and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Motor vehicles are the primary source of transportation in the United States. While this is true for any age group, the older population tend to rely more heavily on automobiles because of easy access and availability, compared to public transportation even when it is available. Older drivers aged 65 years and older are more vulnerable to fatal crashes due to cognitive impairments and frailty. When older drivers are involved in crashes, they sustain higher injury severities compared to younger drivers. One location where older driver experience higher crash risk is intersection, due to the complexity of the situation involving multiple tasks and movements. The objectives of this study were to determine risk factors associated with intersection-related crashes involving older drivers in the Midwestern states and to provide countermeasure ideas to improve safety. Five-year fatal crash data from 2014 to 2018 from the Fatality Analysis Reporting System (FARS) database were utilized, and statistical analysis was carried out to identify characteristics of fatal crashes involving older drivers and risk factors associated with intersection crashes among this age group. Three separate binary logistic regression models were developed to identify statistically significant predictor variables. First model represents older drivers who are involved in fatal single-vehicle crashes. Second model represents fatal multi-vehicle crashes involving at least one older driver, whereas the third model represents fatal single-vehicle crashes involving drivers younger than 65 years for comparison purposes. The dependent variable is whether a fatal crash occurs at an intersection location or not. Many independent variables that include various crash, driver, vehicle, and environmental factors were considered. By considering a 95 percent confidence level, odds ratios were estimated and used to identify relative risk factors of fatal intersection crashes. Analysis showed that controlled intersections, two-way undivided highways, and roads with posted speed limits less than 55 mph increased the risk of fatal single-vehicle and multi-vehicle crashes for older drivers. Fatal single-vehicle crashes were especially prevalent for these drivers. Factors such as urban roadways, driver age older than 75 years, nighttime driving, and speeding increased the risk of single-vehicle fatal intersection crashes, while turning movements and intersecting paths, straight and level roadways, two-lanes highway, and violation of roadway rules increased the risk of multi-vehicle fatal intersection crashes for older drivers. Single-vehicle fatal intersection crash analysis also showed that controlled intersections, two-way undivided highways, roads with posted speed limits less than 55 mph, urban roadways, speeding, nighttime driving, and fixed objects increased the risk of intersection-related fatal single-vehicle crashes, especially for older drivers. However, factors such as straight and level roadways, impaired driving, driver obesity, and the operation of recreation vehicles, buses, or motorcycles increased the risk of single-vehicle fatal intersection crashes for drivers in other age categories. Based on model results, countermeasure ideas to improve the safety of older drivers at intersections as well as other road users were identified. Among suggested ideas, improving intersections designs to accommodate older driver needs is recommended, such as implementing roundabouts when it is appropriate, reach minimum of 75-degree skew angel at intersection, providing protected left turn signals, flashing yellow arrow, restricted crossing U-turn, median U-turn, using rumble stripes along the side of roadway and median, providing transverse rumble strips (TRS) at intersections, improving roadway lighting, signs and markings at intersections and interchanges, implementing roadway diet, enhancing roadway signs and retroreflective delineation, providing cable, guardrail, or concrete barriers, implementing continuous raised-curb medians, enhancing lane drop marking on interchanges, providing acceleration and deceleration lane for merging and diverging locations, providing fixed or portable changeable message signs, enhancing high friction surface treatments on risk prone locations, increasing contrast markings on concrete pavement. Beside the engineering countermeasures, using newer vehicles that equipped with many safety features is advisable to enhance older and other drivers' safety. In addition, older driver license renewal may be modified to be required yearly to overcome early signs of fatigue or cognitive decline to reduce fatal crash risks and enhance safety. Therefore, the results and suggested countermeasures can provide guidance to improve safety of older drivers and other road users.
Download or read book Co-Clustering written by Gérard Govaert and published by John Wiley & Sons. This book was released on 2013-12-11 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cluster or co-cluster analyses are important tools in a variety of scientific areas. The introduction of this book presents a state of the art of already well-established, as well as more recent methods of co-clustering. The authors mainly deal with the two-mode partitioning under different approaches, but pay particular attention to a probabilistic approach. Chapter 1 concerns clustering in general and the model-based clustering in particular. The authors briefly review the classical clustering methods and focus on the mixture model. They present and discuss the use of different mixtures adapted to different types of data. The algorithms used are described and related works with different classical methods are presented and commented upon. This chapter is useful in tackling the problem of co-clustering under the mixture approach. Chapter 2 is devoted to the latent block model proposed in the mixture approach context. The authors discuss this model in detail and present its interest regarding co-clustering. Various algorithms are presented in a general context. Chapter 3 focuses on binary and categorical data. It presents, in detail, the appropriated latent block mixture models. Variants of these models and algorithms are presented and illustrated using examples. Chapter 4 focuses on contingency data. Mutual information, phi-squared and model-based co-clustering are studied. Models, algorithms and connections among different approaches are described and illustrated. Chapter 5 presents the case of continuous data. In the same way, the different approaches used in the previous chapters are extended to this situation. Contents 1. Cluster Analysis. 2. Model-Based Co-Clustering. 3. Co-Clustering of Binary and Categorical Data. 4. Co-Clustering of Contingency Tables. 5. Co-Clustering of Continuous Data. About the Authors Gérard Govaert is Professor at the University of Technology of Compiègne, France. He is also a member of the CNRS Laboratory Heudiasyc (Heuristic and diagnostic of complex systems). His research interests include latent structure modeling, model selection, model-based cluster analysis, block clustering and statistical pattern recognition. He is one of the authors of the MIXMOD (MIXtureMODelling) software. Mohamed Nadif is Professor at the University of Paris-Descartes, France, where he is a member of LIPADE (Paris Descartes computer science laboratory) in the Mathematics and Computer Science department. His research interests include machine learning, data mining, model-based cluster analysis, co-clustering, factorization and data analysis. Cluster Analysis is an important tool in a variety of scientific areas. Chapter 1 briefly presents a state of the art of already well-established as well more recent methods. The hierarchical, partitioning and fuzzy approaches will be discussed amongst others. The authors review the difficulty of these classical methods in tackling the high dimensionality, sparsity and scalability. Chapter 2 discusses the interests of coclustering, presenting different approaches and defining a co-cluster. The authors focus on co-clustering as a simultaneous clustering and discuss the cases of binary, continuous and co-occurrence data. The criteria and algorithms are described and illustrated on simulated and real data. Chapter 3 considers co-clustering as a model-based co-clustering. A latent block model is defined for different kinds of data. The estimation of parameters and co-clustering is tackled under two approaches: maximum likelihood and classification maximum likelihood. Hard and soft algorithms are described and applied on simulated and real data. Chapter 4 considers co-clustering as a matrix approximation. The trifactorization approach is considered and algorithms based on update rules are described. Links with numerical and probabilistic approaches are established. A combination of algorithms are proposed and evaluated on simulated and real data. Chapter 5 considers a co-clustering or bi-clustering as the search for coherent co-clusters in biological terms or the extraction of co-clusters under conditions. Classical algorithms will be described and evaluated on simulated and real data. Different indices to evaluate the quality of coclusters are noted and used in numerical experiments.
Book Synopsis An Introduction to Traffic Flow Theory by : Lily Elefteriadou
Download or read book An Introduction to Traffic Flow Theory written by Lily Elefteriadou and published by Springer Science & Business Media. This book was released on 2013-11-19 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: This text provides a comprehensive and concise treatment of the topic of traffic flow theory and includes several topics relevant to today’s highway transportation system. It provides the fundamental principles of traffic flow theory as well as applications of those principles for evaluating specific types of facilities (freeways, intersections, etc.). Newer concepts of Intelligent transportation systems (ITS) and their potential impact on traffic flow are discussed. State-of-the-art in traffic flow research and microscopic traffic analysis and traffic simulation have significantly advanced and are also discussed in this text. Real world examples and useful problem sets complement each chapter. This textbook is meant for use in advanced undergraduate/graduate level courses in traffic flow theory with prerequisites including two semesters of calculus, statistics, and an introductory course in transportation. The text would also be of interest to transportation professionals as a refresher in traffic flow theory, or as a reference. Students and engineers of diverse backgrounds will find this text accessible and applicable to today’s traffic issues.
Book Synopsis Fatality Analysis Reporting System by :
Download or read book Fatality Analysis Reporting System written by and published by . This book was released on 2007 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Methods to Reduce Traffic Crashes Involving Deer by : James H. Hedlund
Download or read book Methods to Reduce Traffic Crashes Involving Deer written by James H. Hedlund and published by DIANE Publishing. This book was released on 2008-04 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: More than 1.5 million traffic crashes involving deer occur each year in the U.S. These crashes produce $1.1 billion in vehicle damage & 150 fatalities annually. Deer-related crashes are increasing as both deer populations & vehicular travel increase. Many methods have been used in attempts to reduce deer crashes, often with little scientific foundation & limited evaluation. This paper summarizes the methods & reviews the evidence of their effectiveness & the situations in which each may be useful. The only widely accepted method with evidence of effectiveness is well-designed & maintained fencing, with underpasses or overpasses as appropriate. Other methods using advanced technology require substantial additional research & evaluation.
Book Synopsis Statistical Methods by : National Research Council (U.S.). Transportation Research Board
Download or read book Statistical Methods written by National Research Council (U.S.). Transportation Research Board and published by . This book was released on 2005 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Transportation Research Record contains 28 papers dealing with statistical methods in highway safety research; highway safety data, analysis, and evaluation; occupant protection; and systematic reviews and meta-analysis. The papers address such topics as risk and crash prediction models, crashes on freeways and at signalized intersections, multivehicle crash prediction, speed and safety, red light running crashes, freeway lane closures, ramp design, accident exposure, rumble strip benefits, collisions with median trees, intersection safety, accident reconstruction, safety effects of speed limit changes, geometric design and head-on crashes, deer-vehicle crashes, sport utility vehicle rollover, vehicle occupancy and crash risk, a logit model for studying injury severity, abdominal injuries in rail passengers, healthy transport policies, and meta-analysis.
Book Synopsis General Estimates System 1989. A Review of Information on Police-reported Traffic Crashes in the United States by :
Download or read book General Estimates System 1989. A Review of Information on Police-reported Traffic Crashes in the United States written by and published by . This book was released on 1991 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Statewide System for Analysis of Pedestrian and Bicycle Accidents by : Elizabeth L. Linder
Download or read book Statewide System for Analysis of Pedestrian and Bicycle Accidents written by Elizabeth L. Linder and published by . This book was released on 1975 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Statistical and Econometric Methods for Transportation Data Analysis by : Simon Washington
Download or read book Statistical and Econometric Methods for Transportation Data Analysis written by Simon Washington and published by CRC Press. This book was released on 2020-01-30 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book's website (with databases and other support materials) can be accessed here. Praise for the Second Edition: The second edition introduces an especially broad set of statistical methods ... As a lecturer in both transportation and marketing research, I find this book an excellent textbook for advanced undergraduate, Master’s and Ph.D. students, covering topics from simple descriptive statistics to complex Bayesian models. ... It is one of the few books that cover an extensive set of statistical methods needed for data analysis in transportation. The book offers a wealth of examples from the transportation field. —The American Statistician Statistical and Econometric Methods for Transportation Data Analysis, Third Edition offers an expansion over the first and second editions in response to the recent methodological advancements in the fields of econometrics and statistics and to provide an increasing range of examples and corresponding data sets. It describes and illustrates some of the statistical and econometric tools commonly used in transportation data analysis. It provides a wide breadth of examples and case studies, covering applications in various aspects of transportation planning, engineering, safety, and economics. Ample analytical rigor is provided in each chapter so that fundamental concepts and principles are clear and numerous references are provided for those seeking additional technical details and applications. New to the Third Edition Updated references and improved examples throughout. New sections on random parameters linear regression and ordered probability models including the hierarchical ordered probit model. A new section on random parameters models with heterogeneity in the means and variances of parameter estimates. Multiple new sections on correlated random parameters and correlated grouped random parameters in probit, logit and hazard-based models. A new section discussing the practical aspects of random parameters model estimation. A new chapter on Latent Class Models. A new chapter on Bivariate and Multivariate Dependent Variable Models. Statistical and Econometric Methods for Transportation Data Analysis, Third Edition can serve as a textbook for advanced undergraduate, Masters, and Ph.D. students in transportation-related disciplines including engineering, economics, urban and regional planning, and sociology. The book also serves as a technical reference for researchers and practitioners wishing to examine and understand a broad range of statistical and econometric tools required to study transportation problems.
Book Synopsis A Mixed Generalized Ordered Response Model for Examining Pedestrian and Bicyclist Injury Severity Level in Traffic Crashes by : Naveen Eluru
Download or read book A Mixed Generalized Ordered Response Model for Examining Pedestrian and Bicyclist Injury Severity Level in Traffic Crashes written by Naveen Eluru and published by . This book was released on 2007 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Global Status Report on Road Safety by :
Download or read book Global Status Report on Road Safety written by and published by . This book was released on 2009 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately 1.3 million people die each year on the world's roads, and between 20 and 50 million sustain non-fatal injuries. The Global status report on road safety is the first broad assessment of the road safety situation in 178 countries, using data drawn from a standardized survey. The results show that road traffic injuries remain an important public health problem, particularly for low-income and middle-income countries. Pedestrians, cyclists and motorcyclists make up almost half of those killed on the roads, highlighting the need for these road users to be given more attention in road safety programmes. The results suggest that in many countries road safety laws need to be made more comprehensive while enforcement should be strengthened. The Global status report on road safety results clearly show that significantly more action is needed to make the world's roads safer. [Ed.]
Book Synopsis A Novel Approach to Modeling and Predicting Crash Frequency at Rural Intersections by Crash Type and Injury Severity Level by : Jun Deng (Writer on transportation)
Download or read book A Novel Approach to Modeling and Predicting Crash Frequency at Rural Intersections by Crash Type and Injury Severity Level written by Jun Deng (Writer on transportation) and published by . This book was released on 2013 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Safety at intersections is of significant interest to transportation professionals due to the large number of possible conflicts that occur at those locations. In particular, rural intersections have been recognized as one of the most hazardous locations on roads. However, most models of crash frequency at rural intersections, and road segments in general, do not differentiate between crash type (such as angle, rear-end or sideswipe) and injury severity (such as fatal injury, non-fatal injury, possible injury or property damage only). Thus, there is a need to be able to identify the differential impacts of intersection-specific and other variables on crash types and severity levels. This thesis builds upon the work of Bhat et al., (2013b) to formulate and apply a novel approach for the joint modeling of crash frequency and combinations of crash type and injury severity. The proposed framework explicitly links a count data model (to model crash frequency) with a discrete choice model (to model combinations of crash type and injury severity), and uses a multinomial probit kernel for the discrete choice model and introduces unobserved heterogeneity in both the crash frequency model and the discrete choice model, while also accommodates excess of zeros. The results show that the type of traffic control and the number of entering roads are the most important determinants of crash counts and crash type/injury severity, and the results from our analysis underscore the value of our proposed model for data fit purposes as well as to accurately estimate variable effects.
Book Synopsis Analysis of Driver Injury Severity by : Ahmad Khorashadi
Download or read book Analysis of Driver Injury Severity written by Ahmad Khorashadi and published by . This book was released on 2003 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt:
