Download or read book Modeling Intersection Crash Counts and Traffic Volume written by Hans C. Joksch and published by . This book was released on 1998 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling Intersection Crash Counts and Traffic Volume written by Hans C. Joksch, Lidia P. Kostyniuk and published by . This book was released on 1997 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.

Download or read book Highway and Traffic Safety written by National Research Council (U.S.). Transportation Research Board and published by . This book was released on 2000 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Transportation Research Record contains the following papers: Method for identifying factors contributing to driver-injury severity in traffic crashes (Chen, WH and Jovanis, PP); Crash- and injury-outcome multipliers (Kim, K); Guidelines for identification of hazardous highway curves (Persaud, B, Retting, RA and Lyon, C); Tools to identify safety issues for a corridor safety-improvement program (Breyer, JP); Prediction of risk of wet-pavement accidents : fuzzy logic model (Xiao, J, Kulakowski, BT and El-Gindy, M); Analysis of accident-reduction factors on California state highways (Hanley, KE, Gibby, AR and Ferrara, T); Injury effects of rollovers and events sequence in single-vehicle crashes (Krull, KA, Khattack, AJ and Council, FM); Analytical modeling of driver-guidance schemes with flow variability considerations (Kaysi, I and Ail, NH); Evaluating the effectiveness of Norway's speak out! road safety campaign : The logic of causal inference in road safety evaluation studies (Elvik, R); Effect of speed, flow, and geometric characteristics on crash frequency for two-lane highways (Garber, NJ and Ehrhart, AA); Development of a relational accident database management system for Mexican federal roads (Mendoza, A, Uribe, A, Gil, GZ and Mayoral, E); Estimating traffic accident rates while accounting for traffic-volume estimation error : a Gibbs sampling approach (Davis, GA); Accident prediction models with and without trend : application of the generalized estimating equations procedure (Lord, D and Persaud, BN); Examination of methods that adjust observed traffic volumes on a network (Kikuchi, S, Miljkovic, D and van Zuylen, HJ); Day-to-day travel-time trends and travel-time prediction form loop-detector data (Kwon, JK, Coifman, B and Bickel, P); Heuristic vehicle classification using inductive signatures on freeways (Sun, C and Ritchie, SG).

Download or read book Crash Experience Warrant for Traffic Signals written by Hugh W. McGee and published by Transportation Research Board. This book was released on 2003 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Statistical Models of At grade Intersection Accidents written by K. M. Bauer and published by . This book was released on 1996 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research was to develop statistical models of the relationship between traffic accidents and highway geometric elements for at-grade intersections. These models also incorporated the effect of traffic control features and traffic volumes on intersection accidents. The data base used to develop the models was obtained from the California Department of Transportation. Field data were also collected for a sample of urban, four-leg, signalized intersections to provide data on additional geometric design variables and turning-movement counts that were not available from existing highway agency files.

Download or read book Statistical Methods and Modeling and Safety Data Analysis and Evaluation written by National Research Council (U.S.). Transportation Research Board and published by . This book was released on 2003 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Covers empirical approaches to outlier detection in intelligent transportation systems data, modeling of traffic crash-flow relationships for intersections, profiling of high-frequency accident locations by use of association rules, analysis of rollovers and injuries with sport utility vehicles, and automated accident detection at intersections via digital audio signal processing.

Download or read book Development of a Safety Evaluation Procedure for Identifying High risk Signalized Intersections in the Virginia Department of Transportation s Northern Virginia District written by Young-Jun Kweon and published by . This book was released on 2007 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research was undertaken to develop an evaluation procedure to identify high-risk four-legged signalized intersections in VDOT's Northern Virginia district by traffic movements and times of day. By using the developed procedure, traffic engineers are expected to be able to identify signalized intersections where the traffic crash occurrences under different traffic conditions for different times of day are more frequent than would normally be expected. Using generalized linear models such as negative binomial models, one safety performance function was estimated for each of nine crash population reference groups formed by three traffic crash patterns (crash patterns 1, 4, and 6) and four times of day (A.M. peak, mid day, P.M. peak, and evening off peak). Crash pattern 1 is a same-direction crash (rear-end, sideswipe or angle crash) that occurs after exiting the intersection; crash pattern 4 is a right-angle crash between two adjacent straight-through vehicle movements in the intersection; and crash pattern 6 is an angle or head-on or opposite sideswipe crash between a straight-through vehicle movement and an opposing left-turn vehicle movement in the intersection. The procedure developed in this study is based on the empirical Bayes (EB) method. Additional data do not need to be collected in order to use the EB procedure because all the data required for applying the EB procedure should be obtainable from VDOT's crash database and from Synchro input data that are already available to traffic engineers for traffic signal phase plans. Thus, the EB procedure is cost-effective and readily applicable. For easy application of the EB procedure, an EB spreadsheet was developed using Microsoft Excel, and a users' guide was prepared. These are available from the author upon request.

Download or read book A Methodology for Exploring the Relationship Between Intersection Form Factors and Traffic Crashes Using Geographically Weighted Regression written by Reginald Pierre-Jean and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Crashes at intersections are a prominent and problematic traffic safety issue. Crashes at intersections have been studied using global linear regression and before-and-after analytical methods. The Intersection form factors measured are; intersection Legs, traffic signals, traffic calming devices, corners preset, curbs present, sidewalks, percent slope, bridge intersection, park intersection, lane width, number of lanes, and traffic volume. Geographically Weighted Regression (GWR) is novel methodological approach in intersection analysis that models the relationships of these form factors to crash rates within a spatial context. GWR proves to be a more accurate modeling method overall than global linear regression. In addition to higher model performance that GWR exhibits, GWR shows the strength and variation in relationships along the data distribution for each observation. GWR also produces a visual representation of the relationships this allows for greater interpretation of the explanatory variables. In future GWR models with higher specification will produce crash rate prediction layers that will help aid in crash intersection analysis.

Download or read book Validation of Accident Models for Intersections written by Simon Washington and published by . This book was released on 2005 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the results of validation and calibration of motor vehicle crash models for rural intersections. Both the validation and recalibration activities were conducted in pursuit of one overriding research objective, which was to make marginal improvements to an existing set of statistical models for predicting crashes at two and four lane intersections, with the primary intent to be used in the Interactive Highway Safety Design Module (IHSDM). The five types of intersection models for which conclusions are drawn and recommendations are made are: Three-legged stop controlled intersections of two-lane roads; four-legged stop controlled intersections of two-lane roads; three-legged stop controlled intersections with two lanes on minor and four lanes on major road; and four-legged stop controlled intersections with two lanes on minor and four lanes on major road, and signalized intersections of two-lane roads.

Download or read book Crash Models for Rural Intersections written by Andrew Vogt and published by . This book was released on 1999 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of the Relation Between Number of Accidents and Traffic Volume at Divided Highway Intersections written by John W. McDonald and published by . This book was released on 1952 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Joint Modeling of Traffic Related Crashes written by Tammam Nashad and published by . This book was released on 2016 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study contributes to safety literature on transportation safety by employing copula based models for count frequency analysis at a macro-level. Most studies in the transportation safety area identify a single count variable (such as vehicular, pedestrian or bicycle crash counts) for a spatial unit and study the impact of exogenous variables. While the traditional count models perform adequately in the presence of a single count variable, it is necessary to modify these approaches to examine multiple dependent variables for each study unit. To that extent, the current research effort contributes to literature by developing two multivariate models based on copula methodology. First, a copula based bivariate negative binomial model for pedestrian and bicyclist crash frequency analysis is developed. Second, a multivariate negative binomial model for crashes involving non-motorized road users, passenger cars, vans, light trucks and heavy trucks is proposed. The proposed approaches also accommodate for potential heterogeneity (across zones) in the dependency structure. The formulated models are estimated using traffic crash count data at the Statewide Traffic Analysis Zone (STAZ) level for the state of Florida for the years 2010 through 2012. The STAZ level variables considered in our analysis include exposure measures, socio-economic characteristics, road network characteristics and land use attributes. A policy analysis is also conducted along with a representation of hotspot identification to illustrate the applicability of the proposed model for planning purposes. The development of such spatial profiles will allow planners to identify high risk zones for screening and treatment purposes.

Download or read book Safety Performance Functions for Intersections on Highways Maintained by the Virginia Department of Transportation written by Nicholas J. Garber and published by . This book was released on 2010 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, significant effort and money have been invested through research and implemented safety projects to enhance highway safety in Virginia. However, there is still substantial room for improvement in both crash frequency and severity. As there are limits in the available funds for safety improvements, it is crucial that allocated resources for safety improvement be spent at highway locations that will result in the maximum safety benefits. In addition, intersection crashes play a significant role in the safety conditions in Virginia. For example, crashes at intersections in Virginia for the period 2003 through 2007 account for 43.8% of all crashes and 26% of fatal crashes. Therefore, identifying intersections for safety improvements that will give the highest potential for crash reduction when appropriate safety countermeasures are implemented will have a significant impact on the overall safety performance of roads in Virginia. The Federal Highway Administration (FHWA) has developed a procedure for identifying highway locations that have the highest potential for crash reduction (ITT Corporation, 2008). A critical component of this method is the use of safety performance functions (SPFs) to determine the potential for crash reductions at a location. An SPF is a mathematical relationship (model) between frequency of crashes by severity and the most significant causal factors on a specific highway. Although the SafetyAnalyst User's Manual presents several SPFs for intersections, these were developed using data from Minnesota. FHWA also suggested that if feasible, each state should develop its own SPFs based on crash and traffic volume data from the state, as the SPFs that are based on Minnesota data may not adequately represent the crash characteristics in all states. SPFs for intersections in Virginia were developed using the annual average daily traffic as the most significant causal factor, emulating the SPFs currently suggested by SafetyAnalyst. The SPFs were developed for both total crashes and combined fatal plus injury crashes through generalized linear modeling using a negative binomial distribution. Models were also developed for urban and rural intersections separately, and in order to account for the different topographies in Virginia, SPFs were also developed for three regions: Northern, Western, and Eastern. This report covers Phases I and II of the study, which includes urban and rural intersections maintained by VDOT. Statistical comparisons of the models based on Minnesota data with those based on the Virginia data showed that the specific models developed for Virginia fit the Virginia crash data better. The report recommends that VDOT's Traffic Engineering Division use the SPFs developed for Virginia and the specific regional SPFs suggested in this report to prioritize the locations in need of safety improvement.

Download or read book Analysis and Modeling of Relationships Between Accidents and the Geometric and Traffic Characteristics of the Interstate System written by United States. Public Roads Bureau and published by . This book was released on 1969 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Principal findings of this study were that geometrics alone account for only a small portion of the variance in accidents and that no relationship could be established between fatalities and the geometrics studied. The geometrics studied include several types of interchanges, paved shoulders, sight distance, delineators, surface types, and other variables. Mathematical models were developed which can provide estimates of the average number of accidents on a particular type of highway or interchange, using the appropriate variables.

Download or read book Intersection Safety Issue Briefs written by and published by . This book was released on 2004 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling Traffic Accidents at Signalized Intersections in the City of Norfolk VA written by Sharad K. Maheshwari and published by . This book was released on 2010 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This study was an attempt to apply a proactive approach using traffic pattern and signalized intersection characteristics to predict accident rates at signalized intersections in a city's arterial network. An earlier analysis of accident data at selected intersections within the City of Norfolk indicated that in addition to traffic volume, other controllable factors contributed to traffic accidents at specific intersections. These factors included area topography, lane patterns, type of road signs, turning lanes, etc. It is also known that administrative factors such as signal types, signal polic[i]es, road closures, etc., and maintenance factors such as road conditions, condition of the signals, condition of road signs, etc. also impact road accidents. / The objective of this study was to relate these variables to accident rate and delineate variables that are statistically more significant for accident rate. Data on several topographical variables was collected in the City of Norfolk. These variables included number of lanes, turn lanes, pedestrian crossing, restricted lanes, etc. A linear regression model was used to establish relationship between these variables and the accident rate. The resulting regression model explained 60% of the variability. It also showed that four topographical variables are more important than other variables. Those variables included number of lanes, number of turn lanes, presence of median and presence of permanent hazard like railway crossing. However, validation of model showed higher than expected variation. The model developed, in this study, overestimates the accident rate by 33% thus, limiting its practical application."--Executive summary (p. 1).