2013 Session: 439

• Creating Realistic Scenarios for Conducting Virtual Road Safety Audits
  Abstract: With the increasing popularity of driving simulators, an opportunity appears for introducing the technology into the road design process through the process of a virtual road safety audits (VRSA) which focus on adding a human behavior component to the traditional road safety audit process by exposing subjects to a proposed/existing design in a driving simulator. Through the VRSA process, a better understanding of how a design influences the performance of road users can be obtained. Furthermore, by adding the behavioral component to the design process safer roads can be built and the likelihood of expensive reconstructions can be reduced since potential human behavior-related problems can be identified before construction.Although a framework for conducting VRSA is presented the paper is focused on the guidelines developed by the authors to bring scenario representing real life designs to a driving simulator. Among the reasons for focusing on the scenario creation aspect of the procedure is that despite all the benefit of a VRSA, a major roadblock to the process is the requirement of creating driving simulator scenarios representing a realistic road design. Streamlined methods for the creation of realistic scenarios are presented. The processes described rely on custom software, existing engineering design tools, and open source 3d modeling software to create scenarios that cannot be created using the authoring tools typically distributed by driving simulator manufacturers. The authors also decided to explore the feasibility of using LIDAR data for scenario creation and present the resulting produce for a sample road segment.
  Authors: Santiago-Chaparro, Kelvin Roberto; DeAmico, Michael; Bill, Andrea R.; Chitturi, Madhav V.; Noyce, David A.
  Authors: Santiago-Chaparro, Kelvin Roberto; DeAmico, Michael; Bill, Andrea R.; Chitturi, Madhav V.; Noyce, David A.
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-0051
• Assessing Mobility and Safety Impacts of Variable Speed Limit Control Strategy
  Abstract: With the recent advancement in intelligent transportation system, variable speed limit (VSL) has been identified as a potential active traffic management strategy to improve freeway mobility and safety. A number of heuristic VSL strategies have been proposed and evaluated for mobility and safety impact in the literature. The current study proposed and evaluated the safety and mobility impacts of a model predictive VSL control strategy. The proposed VSL strategy performs traffic state prediction using second order traffic flow model and provides a speed that optimizes corridor operational performances. A sensitivity analysis of the VSL update frequency and the safety constraint of the VSL strategy were performed to recommend the best scenario in terms of both safety and mobility. A stretch of Whitemud Drive, an urban freeway corridor in the City of Edmonton, Canada was selected as the study area. The proposed VSL strategy was implemented in the micro simulation platform using a special purpose software module. A real-time collision prediction model was developed for the same study area using matched case-control logistic regression technique to estimate the collision probability for each scenario. The result revealed that the proposed VSL control strategy has the potential to improve both the safety and mobility by approximately 50 and 30 percent, respectively. A VSL update frequency of 5-minutes and a maximum speed difference of 10 km/h between successive time steps yielded the best performances. This finding can be useful for field implementation of the VSL control.
  Authors: Islam, Md. Tazul; Hadiuzzaman, Md.; Fang, Jie; Qiu, Tony Z.; El-Basyouny, Karim
  Authors: Islam, Md. Tazul; Hadiuzzaman, Md.; Fang, Jie; Qiu, Tony Z.; El-Basyouny, Karim
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-0495
• Car Drivers’ Acceptance of ISA Policy Measures
  Abstract: In this paper, car drivers’ acceptability of ISA policy measures is examined by reporting the results of a stated choice experiment conducted in the Netherlands. It is examined to what extent acceptability of mandatory ISA, voluntary ISA with purchase subsidy and voluntary ISA with yearly tax cut varies when targeted at different groups (speed offenders, professional drivers and all drivers) and ISA types (warning ISA and restrictive ISA). The results indicate that acceptability especially varies with the target groups. Mandatory ISA for speed offenders is the policy measure with the highest acceptability among car drivers, while it has the low acceptability when all drivers are targeted. On the other hand, acceptability of mandatory and voluntary ISA options does not differ much between warning and restrictive ISA, although warning ISA increases acceptability if targeted at professional drivers and all drivers, whereas restrictive ISA does for speed offenders. With respect to the two voluntary ISA options, the results indicate that car drivers prefer purchase subsidy above yearly tax cuts. Finally, not much evidence for heterogeneity in acceptability is found although the results indicate that acceptability of ISA policy measures is consistently higher for females and for the older age groups, which is in line with earlier research. Overall, the results suggest that mandatory ISA for speed offenders is acceptable for about two-thirds of the car drivers and may therefore be considered by politicians as an instrument for safer roads.
  Authors: Molin, Eric; van den Bos, Gertjan
  Authors: Molin, Eric; van den Bos, Gertjan
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-0665
• Do Public-Private Partnerships Improve Road Safety? Case of Toll Concessions in Spain
  Abstract: This paper focuses on the implementation of safety based incentives in Public Private Partnerships (PPPs). The aim of this paper is twofold. First, to evaluate whether PPPs lead to an improvement in road safety, when compared with other infrastructure management systems. Second, is to analyze whether the incentives to improve road safety in PPP contracts in Spain have been effective at improving safety performance. To this end, negative binomial regression models have been applied using information from the Spanish high-capacity network covering years 2007-2009. The results showed that even though road safety is highly influenced by variables that are not manageable by the private concessionaire such as the average annual daily traffic, the implementation of safety incentives in PPPs has a positive influence in the reduction of accidents.
  Authors: Rangel, Thais; Vassallo, José Manuel
  Authors: Rangel, Thais; Vassallo, José Manuel
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-0361
• Americans’ Crash Histories and Opinions on Safety Policy
  Abstract: This study examines the impact of driving experience and habits, citation histories, vehicle ownership, and demographics of over 1,000 Americans on their crash risk and safety policy opinions. Model results suggest that increased driver crash probability and decreased support for crash countermeasures correlate with criminal history and high tolerance for risk, both of which are more prevalent among men than women. Non-injury crash involvement (after controlling years of driving, as exposure metrics) appears more common for those with busy lifestyles: those with higher education and more household vehicles. Support for crash safety policies appears largely independent of a person’s (and his/her family’s) crash history, but linked to gender, marital status, and education levels. Women and lower income households are more likely to support safety policies, while those with higher educational obtainment are generally less likely. Finally, results suggest that unfamiliarity may be a key (but surmountable) barrier to introduction technology-based safety policies like speed limiters.).
  Authors: Chen, T. Donna; Kockelman, Kara
  Authors: Chen, T. Donna; Kockelman, Kara
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-1257
• Comparative Analysis of Latin New Car Assessment Program to Global NCAP
  Abstract: The New Car Assessment Program (NCAP) in Latin America and the Caribbean (LAC) began its service in 2010. However, it had only individual test and evaluation protocols to assess adult and child occupant protection performance through an offset frontal crash test without any total scoring and rating scheme. This was the reason why the star ratings in the Euro NCAP and other NCAPs could not be directly compared with the star ratings in the Latin NCAP. In this paper, the relationships among the offset frontal test results and the final star ratings in the global NCAPs—the Euro NCAP, Korean NCAP and Japan NCAP—are evaluated. After that, the relationship is compared to the offset frontal test results of the Latin NCAP. Through this process, this paper focused on estimating the final safety levels of the tested cars in the Latin NCAP. By finding out a linear relationship between the offset frontal test results and the final scores in the global NCAPs through a regression analysis, we tried to estimate the final safety levels of the 18 cars of the Latin NCAP. Consequently, we could conclude that the cars which had been used in Latin NCAP test were not as safe in general as those cars used in other NCAPs.
  Authors: Lee, Seongkwan Mark; Diez Roux, Esteban
  Authors: Lee, Seongkwan Mark; Diez Roux, Esteban
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-1397
• Applying 4E Mitigation Measures to Reduce Rural Roadway Departure Crashes: Holistic Approach
  Abstract: Crashes on two-lane rural roadways involve a disproportionately high number of fatal (K) and serious injury (A) type crashes. Many actions to date have reduced crash severity. As road design guides have evolved, they have incorporated changes that address safety needs. Advanced vehicle designs have incorporated features that protect the occupants. Regulations have addressed risky driver behavior. In order to mitigate rural roadway departure issues, the 4E (engineering, education, enforcement and emergency response) approach has recently been accepted by the United States highway transportation agencies. The need to include non-engineering mitigation measures along with engineering mitigation, such as improved roadway and roadside design and maintenance practices, have positive impacts on rural roadway departure crashes. Improved vehicle designs have positive effects on severity. Improved emergency response has positive effect on survival rate. Education and enforcement efforts have a potentially positive effect on driver behavior. “Moving Ahead for Progress in the 21st Century Act” or “MAP-21” emphasizes on application of 4E approach.This paper presents a data driven model for optimizing allocation of 4E resources at a program level, and also for optimizing an effective combination of 4E mitigation measures at the project level to address rural roadway departure crash issues. The purpose of this paper is to promote a holistic analytical approach by coordinating the use of 4Es and to identify the need for future research to support and validate the proposed optimization approach.Keywords: rural roads; roadway departure; engineering; education; enforcement; emergency response; 4E; holistic approach
  Authors: Kar, Kohinoor; Weeks, Richard Sherman; Satti, Krishna
  Authors: Kar, Kohinoor; Weeks, Richard Sherman; Satti, Krishna
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-1819
• Transportation Safety Planning: Spatial Analysis Approach
  Abstract: In the past decade, considerable efforts have been made to explore various safety conscious planning approaches to form the next-generation planning method, i.e. Transportation Safety Planning (TSP). This study proposes a spatial analysis approach for TSP, with four phases, i.e. Data preparation, Examination of Modifiable Areal Unit Problem (MAUP), Regionalization for Traffic Safety Analysis Zone (TSAZ), and Development of TSP-Prediction Model (TSP-PM). To illustrate the approach, we present a preliminary analysis using Hillsborough County data of Florida (2005-2007). Based on the existing TAZ delineations, we re-regionalized the whole county with zone numbers at an incremental step-size of 50, resulting in 14 zoning schemes. In the regionalization, a multivariate combination of key factors was used as the regionalization criteria, i.e. severe crashes, total road length and total trip production with weights 0.5, 0.25 and 0.25, which respectively reflect the level of safety, transportation facilities, and trips as a major concern at the planning level. Accompanied with a univariate MAUP examination, a total of 64 exploratory TSP-PMs were developed based on the 14 new zoning schemes and three major categories of factors, i.e. intersection density, road length with different speed limit, and trip generation factors. Results showed that as the number of zones increases, the safety interpretation power by transportation system factors decreases while the spatial autocorrelation increases. To the contrary, better model-fitting performance is associated with larger number of zones. Therefore, rational selection of zoning schemes would have to depend on detailed requirements for specific usage of zoning partitions. This research effort is expected to achieve a substantial step toward a new generation of spatial decision support system for TSP practice.
  Authors: Huang, Helai; Xu, Pengpeng; Abdel-Aty, Mohamed A.
  Authors: Huang, Helai; Xu, Pengpeng; Abdel-Aty, Mohamed A.
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-1855
• Road Safety Management: Sight Distance for At-Grade Intersections
  Abstract: The authors of the present paper have long been engaged in developing a Decision Support System (DSS) for road safety management allowing to determine which safety countermeasures on a road network are more effective in reducing the social costs of crashes given a fixed budget for interventions. This paper deals with real speed and rural roads hazard and defines in a better way the components of the driving environments (Scenarios) used in the DSS procedure until now [1, 2]. Attention has been focused to the “Sight Distance “ scenario component which carries out in the at grade intersections. Speed surveys deployed in several years over 11 roads distributed in Tuscany, Campania and Calabria Italian regions and traffic police reports relating to crashes that occurred in nine years on three roads of Campania have been used. Sight distance at intersections has been measured with a laser rangefinder following a standard procedure. In the road network under study scenarios characterized by road type, lighting conditions, presence of water on the pavement, curvature 1/R and sight distance if the scenario happens in at grade intersections have been identified. For each of them hazard has been estimated through the relationship between the vehicles involved in crashes and those passed along the scenario in different environmental conditions. Once defined scenario hazard, the next steps provided for by the system until the definition and choice of interventions are discussed and generalized using only a partial application to scenarios involving curves.
  Authors: de Riso di Carpinone, Vittorio; Grossi, Rodolfo
  Authors: de Riso di Carpinone, Vittorio; Grossi, Rodolfo
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2005
• Evaluating Effectiveness of States' Toward-Zero-Deaths Programs
  Abstract: Since 2001 approximately 30 U.S. states have adopted programs to reduce traffic fatalities to zero with names such as Vision Zero, Target Zero, or Toward Zero Deaths (TZD). TZD is now being promoted as a national strategy by a coalition of transportation and safety groups. Successful TZD programs have five characteristics: 1) an ambitious goal of eliminating traffic fatalities and serious injuries; 2) high levels of inter-agency cooperation in pursuit of the TZD goal among state departments of transportation, public safety, health, and other relevant agencies; 3) a comprehensive strategy addressing all 4 E’s – engineering enforcement, education, and EMS elements of traffic safety; 4) a performance-based, data-driven system of targeting resources and strategies where they will have the greatest impact in reducing traffic fatalities; and 5) policy leadership from relevant entities, including the Governor, the state legislature, and the heads of state agencies. While many of the state TZD programs are relatively new and emerging, four state programs have been around long enough to have enough years of crash data to evaluate the impacts of the programs – Minnesota, Idaho, Utah and Washington. Statistical tests on these four programs support the conclusion that implementing TZD programs accelerates the reduction of fatality rates. The acceleration rate varies from state to state, taking time for a new program to gain its full effect. Although each state has different degrees of temporal effect of its TZD program, the average effect is more and more apparent over time.
  Authors: Munnich, Lee W.; Douma, Frank; Qin, Xiao; Thorpe, J. David; Wang, Kai
  Authors: Munnich, Lee W.; Douma, Frank; Qin, Xiao; Thorpe, J. David; Wang, Kai
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2102
• Benchmarking Road Safety of U.S. States: Frontier Approach
  Abstract: Traffic crashes are still one of the leading causes of death worldwide, although tremendous efforts have focused on their reduction including governmental policies and private organization services. In the United States, federal and state governments strive to establish successful policy initiatives towards the goal of reducing crash frequency and severity. In 2008, the number of traffic fatalities reached its lowest level since 1961 (Traffic Safety Annual Assessment Highlights, 2010). Even though this considerable decrease can be interpreted as a positive sign, which supports ongoing projects, other characteristics of the safety problem are not identified. While some characteristics are discussed in annual crash reports, it is still difficult to construe the reduction in fatalities as a “success”. In this study, a Data Envelopment Analysis (DEA) based benchmarking approach was developed to assess the relative efficiency of individual states toward decreasing traffic fatalities based upon a proposed road safety score. The period considered, 2008, was due to data availability for the seven inputs and four outputs identified. According to the results, 28 states were found to be inefficient and the road safety scores ranged between 0.6 and 1. In addition, safety belt usage, road condition and highway safety expenditures were observed as the most sensitive safety performance indicators (SPIs) to road safety performance.
  Authors: Egilmez, Gokhan; McAvoy, Deborah
  Authors: Egilmez, Gokhan; McAvoy, Deborah
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2122
• Analysis of Residence Characteristics of Drivers, Pedestrians, and Bicyclists Involved in Traffic Crashes
  Abstract: In this study, we investigate the demographic, socioeconomic and travel characteristics of residential areas of the drivers involved in crashes. The main objective of this study is to find out the relationship between crashes and the characteristics of the origin rather than the location of traffic crashes.Various zonal factors based on the postal code (ZIP code) area of drivers' residence were used in the study. ZIP codes were obtained from police crash reports of the year of 2002 and corresponding demographic, socioeconomic and travel characteristics were collected from Census 2000. Five negative binomial (NB) models were estimated for the number of crashes by ZIP area of at-fault drivers (total and severe crashes) DUI drivers, and pedestrians and bicyclists) who were involved in traffic crashes. GIS analyses were also conducted to find out the residence area with many drivers involved in crashes.We found that the demographic and socioeconomic factors such as age, ethnicity, major commuting mode, average travel time to work, household income, occupation, number of households in urban area, and median year of structure built in the area of the residence are associated with the number of traffic crashes.The findings from the study implied that several demographic and socioeconomic as well as travel characteristics of residence zones also contribute to the crash occurrence. Even in the planning phase, we can forecast not only the number of future trips but also the number of crashes with the models in this study. From operational perspective, the results from the study can be used to identify zones with higher potential of at-fault drivers or victims of traffic crashes, thus we can concentrate on these zones for safety treatments including education or stricter enforcement.
  Authors: Lee, Jaeyoung; Abdel-Aty, Mohamed A.; Choi, Keechoo; Siddiqui, Chowdhury Kawsar Arefin
  Authors: Lee, Jaeyoung; Abdel-Aty, Mohamed A.; Choi, Keechoo; Siddiqui, Chowdhury Kawsar Arefin
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2228
• Analysis of Risk Factors Affecting Size and Severity of Traffic Crashes in Riyadh, Saudi Arabia
  Abstract: Recently, growing concern has been shifting towards traffic safety in the kingdom of Saudi Arabia (KSA). KSA has a unique situation regarding traffic safety problems. KSA can be classified as one of the developed countries in terms of the magnitude and quality of the road network available and compatible with international standards. However, it can also be considered as one of the developing countries as the rate of increase in the number of road crashes in the KSA is substantial compared with the relevant figures of other developing countries and other countries of the Gulf region and hence, more research efforts are still needed. This paper aims at better examining the nature and causes of fatal and serious traffic crashes in KSA so that remedies and/or future studies could be suggested. For this purpose, data from 11545 reported fatal and injury traffic crashes that have occurred in Riyadh (the capital of KSA), during the period 2004-2011, were used in the analysis. A Logistic regression model was estimated and the results revealed that crash reason (over-speeding), damages in public property, day of the week, crash location (non-intersection location), and point of collision (head-on) were the significant variables affecting the binary target variable (fatal and non-fatal crashes).In addition, the Structural Equation modeling approach was developed to identify and quantify the impacts of significant variables influencing crash size (e.g., no. of injuries, no. of vehicles involved in the crash), one of the important indices that measure the level of safety of transportation facilities. The results showed that road factor was the most significant factor affecting the size of crash followed by the driver and environment factors. Moreover, a comparison between the characteristics of the Saudi severe crashes and a sample of US severe crashes (as an example of a developed country) are also provided and discussed. The results highlight the need for country specific countermeasures to safety problems.
  Authors: Hassan, Hany M.; Dimitriou, Loukas; Abdel-Aty, Mohamed A.; Al-Ghamdi, Ali Saeed
  Authors: Hassan, Hany M.; Dimitriou, Loukas; Abdel-Aty, Mohamed A.; Al-Ghamdi, Ali Saeed
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2333
• Road Safety Development in Europe: A Decade of Changes (2001-2010)
  Abstract: To evaluate the road safety development in Europe over the last decade, this study presents a new way for measuring the road safety performance change over time, which is to use the technique of data envelopment analysis (DEA) and the Malmquist productivity index. In doing so, we can not only focus on the evolution of road safety final outcomes within a given period, but also take the changes of exposure in the same period into account. In the application, the DEA-based Malmquist productivity index (DEA-MI) has proven valuable as a benchmarking tool for measuring the extent to which the EU countries have improved their road safety performance over the period 2001-2010, and it has derived more objective and insightful results than the ones based on the traditional indicator which only measures the percentage change in road fatalities. The results show considerable road safety progress in most of the Member States during these ten years, and the fatality risk on Europe¡¯s roads instead of the number of road fatalities has actually been reduced by approximately half. However, the situation differed considerably from country to country. The decomposition of the DEA-MI into efficiency change and technical change further reveals that the bulk of the improvement during the last decade was attained through the adoption of productivity-enhancing new technologies throughout the road transport sector in Europe, rather than through the relatively underperforming countries catching up with those best-performing ones.
  Authors: Shen, Yongjun; Hermans, Elke; Brijs, Tom; Wets, Geert
  Authors: Shen, Yongjun; Hermans, Elke; Brijs, Tom; Wets, Geert
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3037
• Modeling and Examining Alcohol-Impaired Driver Behavior and Characteristics for Intersection-Related Crash Severities in New Mexico
  Abstract: Nationally, approximately one third of all motor vehicle crash fatalities involve alcohol-impaired driving. According to the National Highway Traffic Safety Administration (NHTSA), alcohol-impaired motor vehicle crashes cost more than an estimated $37 billion annually. Alcohol impaired driver behavioral activities and demographic characteristics are needed for composing effective countermeasures and developing proper policies against traffic crashes and reducing related costs. This study focuses on the impacts of alcohol impaired driver behavior and characteristics on traffic crash severities at intersections in New Mexico. Statistical analyses were conducted to identify the most significant alcohol impaired driver behavioral activities and demographic characteristics and time periods of driving. The transportation econometric models, multinomial Logit regression models, were developed to analyze crash severities for regular drivers and alcohol impaired drivers using the data collected from the State of New Mexico from 2010 to 2011. The research findings provide a better understanding of traffic alcohol-related accident causes in New Mexico that will help transportation agencies and decision makers find cost-effective solutions for reducing the severity of crashes to improve safety and enhance policy development. Key words: Crash severity, alcohol impaired drivers, discrete choice model, and traffic safety
  Authors: Aluengeh, Davis; Zhang, Guohui
  Authors: Aluengeh, Davis; Zhang, Guohui
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2901
• Examining Fatal Crash Reductions by First Harmful Events Since Introduction of Federal Highway Safety Improvement Program
  Abstract: Although the federal highway safety improvement program (HSIP) has been shown to be associated with the reduction of fatal crashes since 2006, the reasons for these reductions remain largely unknown. This paper examines the reduction of fatal crashes in terms of different types of first harmful events that have potential to provide insight into crash causes and prevention strategies. In this study, fatal crashes were broken down into four types: overturn, collision with motor-vehicle in transport, fixed-object, and collision with non-motorist. Crash data were collected from the Fatal Accident Reporting System (FARS) from 2001 to 2009. Fixed-effects and mixed-effects Poisson models were utilized to estimate the magnitudes of fatal crash reduction by first harmful events for each state. It was found that fatal crashes due to collision with non-motorists and motor vehicles in transport have been reduced by 10 and 5.3 percent, respectively, as compared to the 2001 to 2005 average. Fatal crashes due to overturn and collision with fixed-object were found to decrease in some states but remain unchanged or increase in other states. Nevertheless, the number of national fixed-object and overturn fatal crashes has been reduced by 3 and 0.7 percent, respectively, as a whole. This study also investigated possibilities that could be associated with the magnitudes of the reductions, for instance, the different traffic laws among states, and found that although different safety improvement projects were implemented for targeting different types of crashes, these improvements are also very likely to be beneficial to other crash types. This is referred to as spillover effects. Nationally, fatal crashes have been driven down since the introduction of the HSIP due to the reduction of fatal crashes due to collision with non-motorists and motor vehicles in transport, and partly because of the spillover effects.
  Authors: Wu, Kun-Feng; Pietrucha, Martin T.; Himes, Scott C.
  Authors: Wu, Kun-Feng; Pietrucha, Martin T.; Himes, Scott C.
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-4105
• Driving Simulator-Based Investigations on Impacts of Various Blood Alcohol Concentrations on Driver Behavior
  Abstract: Drinking and driving is a chronic, severe safety problem in the United States, especially for young drivers. A Blood Alcohol Concentration (BAC) of 0.08 or more has been widely used as a measurement to identify alcohol-impaired drivers and analyze their behavior by traffic safety researchers, practitioners, and enforcement agencies. However, previous studies have indicated that drivers can be adversely affected at BACs as low as 0.02, and significant research efforts are needed to identify specific alcohol impacts on driver behaviors at BACs of less than 0.08. This research aims to investigate driver behavior and its safety implications with BACs between 0.00 and 0.08. As a risk-free, cost-effective means, a driving simulator was used in this study. Since drinking and driving is a significant concern for young drivers, licensed drivers between the ages of 21 and 25 were used in the study. Drivers were asked to consume low levels of alcohol and drive through a course in the driving simulator at various BACs. The research results indicate that young drivers are prone to risky behaviors, especially speeding, at low levels of alcohol impairment. They tend to focus on objects to their right, increasing the possibility of head on collisions. The research findings identify significant factors to distinguish alcohol-impaired drivers at low levels of alcohol intoxication and enhance our current understanding of driver impairment cues at low BAC levels. As more states lower their BAC limit for underage drinking drivers, the research methodology and results are of practical importance and can be generalized to detect drivers impaired at low alcohol levels.
  Authors: Metro, Kristal; Zhang, Guohui
  Authors: Metro, Kristal; Zhang, Guohui
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3406
• Genetically Optimized Fuzzy Resource Allocation Model for Improving Road Safety in Interurban Highway Networks
  Abstract: In the current study, optimal strategies of budget allocation for network safety improvement are identified by formulating and solving a possibilistic combinatorial programming problem for a pre-defined set of safety ¡black¢ spots. Specifically, a resource allocation programming problem is constructed, aiming on selecting the locations subset such as to maximize total network safety performance. By adopting the proposed optimization framework, infrastructure management decision-making process is further supported by incorporating experts¢ knowledge/judgment within an optimization mechanism, adding to the robustness and realism of the resulted optimal interventions schedule. The proposed possibilistic problem setup is tackled by suitable transformations of a hybrid stochastic approximation optimization routine, namely, Genetic Algorithm. Computational results from the proposed framework implementation onto a part of realistic highways network are exhibiting the ability of an optimization framework to maximize the invested capital performance (by utilizing almost 30% of the total capital required for upgrading all ¡black¢ spots, a reduction of nearly 73% of the total accidents cost is eliminated). Finally evidences are provided on the role of uncertainty in budgetary managerial decisions. In particular, for the dataset used, a difference of 6% has been identified (in favour of the confidence of the invested capital performance in reducing casualties) in the composition of the selected locations, an element of significant importance for realistic applications.
  Authors: Dimitriou, Loukas; Abdel-Aty, Mohamed A.
  Authors: Dimitriou, Loukas; Abdel-Aty, Mohamed A.
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3646
• Developing Safety Management Tools for State Departments of Transportation
  Abstract: Two different safety management tools had been recently developed for the California Department of Transportation (Caltrans): one is the Continuous Risk Profile (CRP) approach which is a network screening procedure, and the other is the California Safety Analyst (CASA) which is a web-based application designed to assist state safety engineers in conducting safety investigations and documenting their findings. This paper provides a qualitative description of these two tools and also summarizes feedback from over 100 Caltrans safety engineers who attended the demonstration of the web-based application. Findings from empirical analysis and the survey revealed that CRP can significantly reduce the false positive rate and that CASA can greatly improve the efficiency of traffic safety investigations. However, there still remain misunderstandings about the relationship among CRP, other methods explained in Highway Safety Manual, and different safety management tools. These misunderstandings impose challenges for the deployment of CRP and CASA in California and these challenges are also discussed in the paper.
  Authors: Chung, Koohong; Grembek, Offer; Lee, Jinwoo
  Authors: Chung, Koohong; Grembek, Offer; Lee, Jinwoo
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3936
• Do Lower-Income Areas Have More Pedestrian Casualties?
  Abstract: Pedestrian and motor vehicle casualties are analyzed with geo-coded data for the State of New Jersey with the objective of determining how the income of an area may be associated with casualties. We develop a maximum-likelihood negative binomial model to examine how various spatially defined variables, including road, income, and vehicle ownership, may be associated with casualties using census block-group level data. Due to suspected spatial correlation in the data we also employ a conditional autoregressive Bayesian model using Markov Chain Monte Carlo simulation, implemented with Crimestat software. Results suggest that spatial correlation is an issue as some variables are not statistically significant in the spatial model. On the substantive question of how income may affect casualties, we find that both pedestrian and motor vehicle casualties are greater in lower income block groups. Both are also associated with less household vehicle ownership, which is not surprising for pedestrian casualties, but is a surprising result for motor vehicle casualties. Controls for various road categories provide expected relationships. Individual level data is further examined to determine relationships between the location of a crash victim and their residence zip code.
  Authors: Noland, Robert B.; Klein, Nicholas J.; Tulach, Nicholas K
  Authors: Noland, Robert B.; Klein, Nicholas J.; Tulach, Nicholas K
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-4604
• Analysis Framework for Evaluation of Traffic Compliance Measures
  Abstract: Agencies and practitioners are often testing new and innovative strategies for improving driver compliance with traffic regulations. However, in evaluating these strategies, researchers often rely on simple before-and-after methods that suffer from several flaws and can result in misleading results and an inaccurate assessment of a strategy’s effectiveness. This paper examines these flaws, proposes a framework that avoids or corrects for them, and then uses it to analyze the effectiveness of a common strategy: using larger signage. The framework described in this paper can be applied to a wide range of driver compliance situations, such as yielding at pedestrian crossings, speed limit obedience, and proper anticipation of roadway features such as speed humps or intersections.
  Authors: Campbell, Robert; Skabardonis, Alexander
  Authors: Campbell, Robert; Skabardonis, Alexander
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-5316
• Quasi-Experimental Study of Traffic Calming Measures in New York City
  Abstract: This paper provides a large-scale, rigorous evaluation of traffic calming projects in the U.S. The study area is New York City, which treated 391 streets with speed tables between 1996 and 2003. Based on crash frequencies for 5 years before treatment and 5 years after, for both treated streets and well-matched comparison streets, there is no evidence that New York City’s ambitious traffic calming program has led to a reduction in total crashes, pedestrian crashes, or injury crashes. This is in contrast to earlier, less carefully controlled evaluations that have reported significant reductions in crashes with traffic calming.
  Authors: Ewing, Reid; Chen, Li; Chen, Cynthia
  Authors: Ewing, Reid; Chen, Li; Chen, Cynthia
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2242
  Practice-Ready: Yes
• Do Road Safety Communication Campaigns Work? How to Assess the Impact of a National Fatigue Campaign onDriving Behavior
  Abstract: Road safety communication campaigns are considered as an efficient strategy to approach the wide audience, aiming at the reduction of the number and severity of road crashes, by influencing road users’ behavior. Though, despite the large number of campaigns that been designed and implemented in the last years, a rather low proportion of them has been formally evaluated. Towards this direction, the objective of this paper is to present the evaluation design and implementation for the effectiveness on driving behavior of a national road safety communication campaign on fatigue, targeting primarily professional drivers, and, secondarily, all other drivers. The definition of the objectives of the campaign were addressed through the Health Belief Model, and included the increase of the awareness of the severity of driving while fatigued and the relative proposal of effective countermeasures. The measurement variables of the evaluation design, also addressed by the Health Belief Model, were knowledge, behavioral beliefs, risk comprehension, behavioral intentions, past behavior and self-reported behavior. The evaluation was based on a non-experimental design, since, it was not feasible to use control group(s), as the whole population was exposed to the campaign, and data was collected, within a face-to-face questionnaire survey, conducted, before, during and after the campaign implementation. Process and outcome evaluations were conducted for the assessment of the impact of the campaign on driving behavior, and results showed that the audience was reached at a mean rate of 13%, with the distribution of the campaign leaflets, working as the most effective media channel (70%). In addition, a statistically significant increase was observed in the proportion of respondents that were aware of the causes and effects of fatigue while driving, and similar results were indicated when testing behavioral beliefs, risk comprehension, behavioral intentions and past behavior. The main message of the campaign reached both the primary and secondary target groups, and was validated by the increase of the percentage of the professional drivers and all other drivers, self-reporting that they stop and rest for 15 minutes in the during and after phases, compared to the before phase.
  Authors: Nathanail, Eftihia G.; Adamos, Giannis; Kapetanopoulou, Paraskevi
  Authors: Nathanail, Eftihia G.; Adamos, Giannis; Kapetanopoulou, Paraskevi
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-4152
  Practice-Ready: Yes
• Comparison Between Traditional Methods and Empirical Bayes with Safety Performance Function Method for Identifying High Crash-Risk Intersections
  Abstract: Identifying high crash-risk locations, called hot-spots, is a most important step to improve roadway safety and the Empirical Bayes (EB) coupled with the safety performance function (SPF) is regarded as the state of practice in identifying such locations. To apply the EB-SPF method, however, requires considerable resources in preparing data and statistical expertise. Consequently, many highway agencies still rely on traditional methods such as crash frequency and crash rate in identifying locations for potential safety improvement without knowing the extent of accuracy of such methods.This study examined four traditional identification methods widely used to understand the extent of accuracy of the four methods in identifying potential locations for safety improvement as compared to the EB-SPF method and to suggest the best method among the four: crash frequency, crash rate, rate-quality control, and equivalent property damage only (EPDO). This study was limited to 4-leg intersections with either signal or 2-way stop and 2004-2008 data were collected at 1,670 such intersections. The study found that the crash frequency method performed the best among the four in correct identification of top 1 percent unsafe intersections yet tends to flag intersections falsely being at top hot-spots and the rate-quality control method performed the best for the top 5 and 10 percent unsafe intersections. The findings are expected to help highway agencies continuing use of the traditional methods choose the best so that scarce resources available for safety improvement would be invested effectively.
  Authors: Lim, In-Kyu; Kweon, Young-Jun
  Authors: Lim, In-Kyu; Kweon, Young-Jun
  Year: 2013
  Document Type: Paper
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-4035
  Practice-Ready: Yes
• Creating Realistic Scenarios for Conducting Virtual Road Safety Audits
  Authors: Santiago-Chaparro, Kelvin
  Authors: Santiago-Chaparro, Kelvin
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-0051
• Americans' Crash Histories and Opinions on Safety Policy
  Authors: Kockelman, Kara
  Authors: Kockelman, Kara
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-1257
• Evaluating Effectiveness of States' Toward-Zero-Deaths Programs
  Authors: Qin, Xiao
  Authors: Qin, Xiao
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2102
• Analysis of Residence Characteristics of Drivers, Pedestrians, and Bicyclists Involved in Traffic Crashes
  Authors: Lee, Jaeyoung
  Authors: Lee, Jaeyoung
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2228
• Analysis of Risk Factors Affecting Size and Severity of Traffic Crashes in Riyadh, Saudi Arabia
  Authors: Hassan, Hany
  Authors: Hassan, Hany
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2333
• Modeling and Examining Alcohol-Impaired Driver Behavior and Characteristics for Intersection-Related Crash Severities in New Mexico
  Authors: Aluengeh, Davis
  Authors: Aluengeh, Davis
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-2901
• Road Safety Development in Europe: A Decade of Changes (2001-2010)
  Authors: Shen, Yongjun
  Authors: Shen, Yongjun
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3037
• Road Safety Development in Europe: A Decade of Changes (2001-2010)
  Authors: Hermans, Elke
  Authors: Hermans, Elke
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3037
• Driving Simulator-Based Investigations on Impacts of Various Blood Alcohol Concentrations on Driver Behavior
  Authors: Metro, Kristal
  Authors: Metro, Kristal
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3406
• Developing Safety Management Tools for State Departments of Transportation
  Authors: Chung, Koohong
  Authors: Chung, Koohong
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-3936
• Comparison Between Traditional Methods and Empirical Bayes with Safety Performance Function Method for Identifying High Crash-Risk Intersections
  Authors: Lim, In-Kyu
  Authors: Lim, In-Kyu
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-4035
• Examining Fatal Crash Reductions by First Harmful Events Since Introduction of Federal Highway Safety Improvement Program
  Authors: Wu, Kun-Feng
  Authors: Wu, Kun-Feng
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-4105
• Do Lower-Income Areas Have More Pedestrian Casualties?
  Authors: Noland, Robert
  Authors: Noland, Robert
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-4604
• Analysis Framework for Evaluation of Traffic Compliance Measures
  Authors: Campbell, Robert
  Authors: Campbell, Robert
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-5316
• Do Public-Private Partnerships Improve Road Safety? Case of Toll Concessions in Spain
  Authors: Rangel, Thais
  Authors: Rangel, Thais
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-0361
• Assessing Mobility and Safety Impacts of Variable Speed Limit Control Strategy
  Authors: El-Basyouny, Karim
  Authors: El-Basyouny, Karim
  Year: 2013
  Document Type: Presentation; Poster
  Subject: Safety and Human Factors
  Session: 439
  Paper Number: 13-0495