Measuring Pedestrian Exposure and Risk at High-Risk Intersections
Shaunna Burbidge, Avenue ConsultantsShow Abstract
This research aims to increase the understanding of conflicts between pedestrians and vehicles during crossings by identifying reckless pedestrian and driver behaviors that may contribute to an increased risk of conflicts or crashes. Existing research has focused on conditions present just prior to or during a crash but has nearly ignored the significant number of interactions between pedestrians and vehicles that do not end in a crash. These near miss incidents or conflicts may provide significant insight into what travel behaviors or conditions precipitate a crash. Observations of 2,062 individual pedestrian crossings at eight high-risk intersections along Utah’s urban core are analyzed here. Data was collected using both video footage from Department of Transportation Traffic Operations Cameras and on-site observations. All crossings were coded based on pedestrian demographics, crossing behaviors, interactions or conflicts with vehicles and driver behavior. Results suggest that a significant number of conflicts occur when a vehicle is turning right or when a vehicle stops in a crosswalk. Additionally, distracted pedestrians, people who walk slowly, and those walking alone are significantly more likely to be involved in a conflict with a vehicle.
Is the Safety in Numbers Effect Still Observed in Areas with Low Pedestrian Activities?: A Case Study from Central Florida
Jaeyoung Lee, Central South UniversityShow Abstract
Mohamed Abdel-Aty, University of Central Florida
Pengpeng Xu, University of Hong Kong
Yaobang Gong, University of Central Florida
Active modes of transportation (i.e., walking and cycling) have been promoted as they are sustainable and improve public health. However, pedestrians and bicyclists are more exposed to traffic fatalities and injuries, and their higher crash risk has prevented people to choose such active modes. In the previous studies, the safety-in-numbers (SIN) effect have been found, which is a phenomenon that when the number of pedestrians or cyclists increase, their crash rates decrease. The previous studies used data from highly populated areas. It is questionable that the SIN is still valid in areas with a low population density and small number of pedestrians. Thus, this study aims at analyzing pedestrian crashes in a suburban area in Central Florida and exploring if the SIN effect is also observed. We employ a Bayesian random-parameter Poisson-lognormal model. The results show that the SIN effects were found only at 32 intersections out of 219. The intersections with the SIN have relatively larger pedestrian activities whereas those without the SIN have extremely small pedestrian activities. It implies that just encouraging walking might result in serious pedestrian safety issues in a suburban area without sufficient pedestrian activities. Therefore, on one hand, it is required to encourage more people to walk. On the other hand, it is also required to establish and implement an effective plan to minimize traffic crashes involving pedestrians, especially in areas with small number of pedestrians.
Modeling Violation Counts of Pedestrians and Cyclists on the Brooklyn Bridge Promenade
Lai Zheng, Harbin Institute of TechnologyShow Abstract
Tarek Sayed, University of British Columbia
Mohamed Hussein, McMaster University
The Brooklyn Bridge Promenade is a typical non-motorized shared space with a centerline marking to separate pedestrians and cyclists. Violations that involve pedestrians and cyclists crossing the centerline to an undesignated path may lead to unexpected interactions and even collisions. This study aims at modelling violations of pedestrians and cyclists at an aggregate level and investigating the contributing factors to the violation frequency. Specifically, violation counts of 5-minute intervals are predicted as a function of traffic flow and other geometry-related variables, using the univariate Poisson log-normal model. In order to account for possible temporal correlation in the time series counts as well as the mode correlation between the two types of violations, fixed-over-time-effects models and multivariate models are further developed. A mixed procedure is introduced to the multivariate model to allow different covariate sets for pedestrian and bicycle violations. The model comparison results show that introducing the fixed-over-time-effects makes no substantial difference from the standard models, while the multivariate models outperform the univariate models. Results also show that variables such as pedestrian/cyclist count, width of path, length of path have significant influence on at least one type of violations (pedestrian or bicycle violation), while the influence of directional distribution and speed-related variables are insignificant. An interesting finding is that, some common variables such as cyclist count and the width of cyclist path, have significantly opposite effects on violations of pedestrians and cyclists.
Diagnostic Analysis of the Effects of Weather Condition on Pedestrian Crash Severity
Xiaoqi Zhai, Central South UniversityShow Abstract
Huang Helai, Central South University
N.N. Sze, The Hong Kong Polytechnic Universtiy
Kai Kwong HON, Aviation Weather Services Branch, Hong Kong Observatory, Tsim Sha Tsui, Hong Kong
Pedestrians are vulnerable to severe injury and mortality in the road crashes. Numerous studies have attempted to identify factors contributing to the crashes and injury risks of pedestrians. As an active transport mode, walking behavior is sensitive to the changes in weather condition. However, it is not common that comprehensive real-time weather data be available for road safety analysis. In this study, high resolution weather data in the terms of temporal and spatial distribution were integrated with the crash data, using the Geographical Information System (GIS) approach. Then, a mixed logit model was established to measure the association between pedestrian crash severity and possible risk factors. Also, the interaction effects by weather condition on the association were considered to examine the pedestrians’ and drivers’ risk behavior under adverse weather condition. Results indicated that high temperature and presence of rain were associated with higher likelihood of Killed and Severe Injury (KSI) crashes. Also, high temperature and presence of rain could moderate the effects of convicted driver and pedestrian behaviors on crash severity. Results were indicative to real-time traffic control and management measures that could enhance the pedestrian safety, and therefore promote the walkability in the long run.
Louisiana Pedestrian Crash Analysis with Multi-Nomial Logit Model and Bayesian Network
Ming Sun, University of Louisiana, LafayetteShow Abstract
Xiaoduan Sun, University of Louisiana at Lafayette
Donghui Shan, CCCC First Highway Consultants Co., Ltd
Destiny Armstrong, University of Louisiana, Lafayette
Subasish Das, Texas A&M Transportation Institute
Pedestrians are the most vulnerable users of highway transportation system. While encouraging “Green Transportation”, a concerning fact emerges in the United States: pedestrian deaths are climbing faster than motorist fatalities, reaching nearly 6,000 in 2016 - the highest in more than two decades. In Louisiana, pedestrian fatalities reached 110 in 2015, nearly 15% of total traffic fatalities. In the same year, Louisiana pedestrian fatality rate (pedestrian fatalities per 100,000 population) is 2.18, higher than the U.S. average of 1.67. This paper presents an analysis of Louisiana pedestrian crashes from 2006 to 2015 with the multinomial logit and Bayesian networks models to explore the potential relationship between pedestrian injury severity and a host of factors including pedestrian behavior, demographics, and built environment. The MNL model is utilized to identify the significant factors, and the BN model is structured to reveal probabilistic dependence between pedestrian crash severity and explanatory variables. The results indicate that fatal and severe crashes are closely linked to pedestrians’ alcohol or drugs involvement and older age. The probability of having a fatal or severe injury crash is much higher for pedestrian traveling on roadways away from intersection area (i.e., crossing street or walking along or against roadway). The likelihood of pedestrian crashes resulting in fatality or severe injury increases 49% by walking on unlighted roadways with a speed limit higher than 60 mph at night. The findings of this study show some unique characteristics of pedestrian crashes in Louisiana, which can be useful in selecting the targeted countermeasures.
Proactive Approach for Pedestrian Safety Evaluation Using Choice Model for Unprotected Mid-Block Crossings Under Mixed Traffic Conditions
Avinash Chaudhari, Research ScholarShow Abstract
Jiten Shah, IITRAM
Shriniwas Arkatkar, Sardar Vallabhbhai National Institute of Technology, Surat
Gaurang Joshi, Sardar Vallabhbhai National Institute of Technology
Manoranjan Parida, Indian Institute of Technology, Roorkee
Mid-block crosswalks act as imaginary bridge between adjoining activities based on a particular land-use type on both side of the road. At unprotected mid-block pedestrian crossing, the chance of conflict is high particularly under heterogeneous traffic conditions during crossing. This paper investigates pedestrians’ safety at mid-block street crossing in Western and Northern part of India at nine different urban locations. The pedestrian safety can be evaluated by proactive methods. Proactive method is a cost-effective and less time consuming technique as compared to the historic crash data analysis. A binary logistic regression model was developed to examine the effect of various factors on the PSM values as well as predicting the probability to avoid conﬂict with an approaching vehicle and parameters of pedestrians’ decisions. From the study, it is observed that pedestrian behavioural characteristics such as rolling behaviour and roadway characteristics signiﬁcantly reduce the PSM values. From the elastic analysis, it was found that the vehicle gap, vehicle speed, pedestrian speed, concentration on vehicle gap, platoon size has positive effect whereas, rolling behaviour, pedestrian age, land use has negative effect. Further, from the sensitivity analysis, it was found that the pedestrian safety decreases with increase in vehicle speed, number of lanes and rolling behaviour. The probability of avoiding collision with approaching vehicle was decreases with respect to the type of vehicle although, it increases with increase in vehicular gap. The results of the present paper may be useful to design pedestrian facility and suggest appropriate remedial measures to improve pedestrian safety.
Pedestrian Injury Severity Versus Vehicle Impact Speed: Uncertainty Quantification and Calibration to Local Conditions
Gary Davis, University of Minnesota, Twin CitiesShow Abstract
Christopher Cheong, University of Minnesota, Twin Cities
This paper describes a method for fitting predictive models relating vehicle impact speeds to pedestrian injuries, where results from a national sample are calibrated to reflect local injury statistics. Three methodological issues identified in the literature: outcome-based sampling, uncertainty regarding estimated impact speeds, and uncertainty quantification, are addressed by (i) implementing Bayesian inference using Markov Chain Monte Carlo sampling and (ii) applying multiple imputation to conditional maximum likelihood estimation. The methods are illustrated using crash data from the Pedestrian Crash Data Study coupled with an exogenous sample of pedestrian crashes from Minnesota’s Twin Cities. The two approaches produced similar results and, given a reliable characterization of impact speed uncertainty, either approach can be applied in any jurisdiction having an exogenous sample of pedestrian crash severities.
The Challenge of Safe and Active Transportation: Examination of Pedestrian and Bicycle Crashes in the Austin District
Ipek Sener, Texas A&M Transportation InstituteShow Abstract
Kyuhyun Lee, Korea Land and Housing Corporation
Joan Hudson, Texas A&M Transportation Institute
Michael Martin, Texas A&M Transportation Institute
Boya Dai, Texas A&M Transportation Institute
Motivating the use of nonmotorized modes of transportation is a never-ending goal at the intersection of public health and transportation given its numerous benefits to individuals and communities. However, with such growth comes an undesirably increased exposure of pedestrians and bicyclists to conflicts with motor vehicles. About 4,000 fatal and serious injury crashes involving a motor vehicle and a pedestrian or bicyclist occurred between 2007 and 2014 in the Texas Department of Transportation (TxDOT) Austin District. This study contributed to this field of research by developing a detailed understanding of crashes involving pedestrians and bicyclists in the Austin District of TxDOT. Four crash frequency and severity models were developed for pedestrians and bicyclists in the district using the crashes ending in fatality (K), incapacitating injury (A), and non-incapacitating injury (B) during the eight-year period, aggregated at the block-group level. The crash frequency and severity models identified the factors associated with the frequency of KAB crashes and the presence of severe crashes (KA). The models showed the important role of different variables in crash frequency and severity, including motor vehicle traffic and commute characteristics, land use attributes, infrastructure identifiers, population and demographic characteristics, and household and housing unit characteristics. Using the model results, areas of concern with the greatest potential for safety improvements were identified based on a methodology adapted from the Federal Highway Administration. The results of this study can be used to develop proactive countermeasures and targeted safety improvement interventions that reduce crash frequency and severity for nonmotorized users.
From Temporary to Permanent: A Way to Enhance Road Safety in Indian Cities: Evidence from Mumbai
Dhawal Ashar, World Resources InstituteShow Abstract
Roads in the last century were designed for movement of vehicles and goods. This automobile dependency came with a set of negative externalities including air pollution, congestion, greenhouse gas emissions and traffic crashes. Around 1.3 million people lose their lives in road traffic crashes every year and that the road safety problem is now an epidemic is no surprise too. However, this trend is only on the rise. And when it comes to urban areas, over 50% of road traffic fatalities are pedestrians, followed by motorcyclists and bicyclists. Mumbai, with a population of 12.44 million is no exception to this. Crash data from Mumbai confirms that 51% of fatalities in road traffic crashes are of pedestrians, while the mode share states that 51% trips are walk trips. Therefore, road safety in the urban context is perhaps more a design issue, than enforcement or education. While road design prioritizes movement of vehicles, it also maintains a minimum sidewalk width in the cross section. This, however, does not mean clear and better walking conditions, as is evident by the severely high number of pedestrian crashes. This paper documents the process of safe street design and implementation in Mumbai and the role of different actors in the process. It narrates, with evidence, a disruptive approach to introduce principles of safe streets design in the city and draws learnings from temporary transformations on major high-risk intersection in Mumbai city. Keywords: Transportation planning, tactical urbanism, temporary measures, long term change, road safety
Empirical Analysis of the Impact of Vehicle Type on Injury Severity In-Vehicle–Pedestrian Crashes
Steven Stapleton, Michigan State UniversityShow Abstract
Timothy Gates, Michigan State University
Pedestrian fatalities continue to be a large problem in the United States, with pedestrian fatalities increasing every year, and increasing at a more rapid pace than motor vehicle crashes. While some attribute these increases with distracted driving, alcohol, or lighting conditions, these factors have not changed in recent years. On the other hand, media reports have begun attributing this increase to the increasing proportion of SUVs on the road. This study sought to evaluate that hypothesis by evaluating crash severity probability based on the proportion of vehicle registrations per county per year by vehicle type, as well as with the proportion of observed vehicles collected from annual safety belt surveys. Ordered logit regression was performed, finding that as SUVs increase as a proportion of both registered and observed vehicles increase, pedestrian crashes are likely to be more severe.
Impact Speed and Probability of Pedestrian Fatality: A Systematic Review and Meta-Analysis
Qinaat Hussain, Transportation Research Institute (IMOB) UhasseltShow Abstract
Hanqin Feng, School of Mathematics and Statistics UNSW
Raphael Grzebieta, Transport and Road Safety (TARS) Research
Tom Brijs, Universiteit Hasselt
Jake Olivier, University of New South Wales
Background: Pedestrians struck in motorised vehicle crashes constitute the largest group of traffic fatalities worldwide. Excessive speed is the primary contributory factor in such crashes. The relationship between impact speed and the risk of a pedestrian fatality has generated much debate concerning what should be a safe maximum speed limit for vehicles in high pedestrian active areas. Methods: Four electronic databases (MEDLINE, EMBASE, COMPENDEX, SCOPUS) were searched to identify relevant studies. Records were assessed, and data retrieved independently by two authors in adherence with the PRISMA statement. The included studies reported data on pedestrian fatalities from motorised vehicle crashes with known impact speed. Summary odds ratios (OR) were obtained using meta-regression models. Time trends and publication bias were assessed. Results: Fifty-five studies were identified for a full-text assessment, 27 met inclusion criteria, and 20 were included in a meta-analysis. The analyses found that when the impact speed increases by 1km/h, the odds of a pedestrian fatality increases on average by 11% (OR=1.11, 95%CI: 1.10-1.12). The risk of a fatality reaches 5% at an impact speed of 28km/h, 10% at 36km/h, 50% at 57km/h, 75% at 67km/h and 90% at 78km/h. Evidence of Publication bias and time trend bias among included studies were found. Conclusions: The results of the meta-analysis support setting speed limits of 30 to 40 km/h for high pedestrian active areas. These speed limits are commonly used by best practice countries that have the lowest road fataility rates and that practice a Safe System Approach to road safety.
Self-Reported Pedestrian Mid-Block Crossing Behavior: Effects of Gender, Age, and Region
Muhammad Abdullah, University of Management and TechnologyShow Abstract
Takashi Oguchi, The University of Tokyo
Charitha Dias, Qatar Universiy
This study explores unobservable factors which describe pedestrian mid-block crossing behavior. A mid-block is a location away from intersections where pedestrians cross in the absence of a crosswalk. An online questionnaire was developed that included 24 (5-point Likert type) items about pedestrian behaviors, mobility patterns, preferences, perceptions and attitudes along with demographic questions. 220 respondents (139 men and 81 women) from various developing and developed countries between the ages of 18 and 59 answered the questionnaire. Exploratory factor analysis produced four factors: risk-taking, wrong perception, walking for pleasure and walking pattern. Risk-taking and wrong perception had good internal reliability while walking for pleasure and walking pattern were not internally consistent. The effects of demographic variables on the factor scores were investigated. Men declared more risk-taking behavior as compared to women. Pedestrians in the age group 18-29 declared more risk-taking behavior as compared to the ones in the age group 30-39. Interestingly, region had no significant impact on risk-taking behavior. A weak correlation was discovered between signal violations and risk-taking behavior at mid-block. The results of the study provide better understanding of mid-block crossing behavior and can be helpful in planning and design of pedestrian crossing facilities at mid-block.
Evaluation of Visibility and Effects of a Road Surface Projection System for Uncontrolled Crosswalks Based on Driving Simulation
Ko Takahashi, Toyohashi University of TechnologyShow Abstract
Kojiro Matsuo, Toyohashi University of Technology
Genta Yonekawa, Toyohashi University of Technology
Yoshihiro Terakura, Kictec. Co. Ltd.
Nao Sugiki, Toyohashi University of Technology
In Japan, since almost 70% of the pedestrian fatalities occur at night, it is very important to reduce the vehicle-pedestrian crashes at night. One way to reduce these serious crashes will be the improvements of the visibility of the road markings at night to encourage drivers to pay attention. Recently, crosswalk alert systems (CAS) which highlight an uncontrolled crosswalk when pedestrians are present have been implemented. This paper aims to verify the effectiveness of CAS with a road surface projection system (RSP-CAS) that projects pictograms and/or characters onto a road surface only when pedestrians are waiting to cross at an uncontrolled crosswalk. Firstly, through a driving simulator experiment, we compared the driver response to a normal road marking and that to an RSP-CAS. As a result, we could see the slight difference of the increase in the average stop rate for yielding the right-of-way to pedestrians between the normal road marking group and the RSP-CAS group. Next, we conducted an experiment and surveyed subjects for evaluating the visibility and the impact on forward attention of 23 projection patterns, as well as one normal road marking. The results showed that the patterns characters arranged in the lateral direction and the pictograms which are simple and instantaneously easy to understand had higher visibility and high impact on forward attention.
Investigating Secondary Interactions: Are Drivers Paying Attention to Pedestrians When Exiting Non-Signalized Intersections?
Ting Fu, University of WaterlooShow Abstract
Weichao Hu, McGill University
Nicolas Saunier, Ecole Polytechnique de Montreal
Luis Miranda-Moreno, McGill University
Most studies investigating pedestrian-vehicle interactions at non-signalized intersections have focused on interactions at the crosswalk on the same approach the vehicle is coming from, which are called primary interactions in this study. However, secondary interactions, defined as interactions between vehicles exiting the intersection and crossing pedestrians, have not been studied by themselves; these interactions can be dangerous due to driver’s unclear knowledge of right-of-way, acceleration attempts to recover the speed, and the complex situation the driver faces in the intersection. This paper’s goal is to highlight the safety issue of secondary pedestrian-vehicle interactions at non-signalized intersections. For that purpose, a case study involving ten all-way stop intersections from Montreal, Canada, was conducted by collecting video data. Different measures are used in the study: from the interaction analysis (behavior measures based on a Distance-Velocity model), average crossing speed analysis and vehicle approaching behaviour analysis (approaching speed and acceleration). Primary and secondary interactions are analyzed and compared. Results show that secondary interactions are more dangerous compared to primary interactions. Among the three secondary interaction types, secondary through interactions are the most dangerous.
The Impact of Movement Speed on Pedestrians’ Obstacle Avoidance
Abdullah Noor Alhawsawi, University of MelbourneShow Abstract
Majid Sarvi, University of Melbourne
Milad Haghani, University of Melbourne
Abbas Rajabifard, University of Melbourne
Computer-based simulations of pedestrian crowds have become an attractive field for scientific research. Computer-based simulations provide improved results that help enhance evacuation plans and reduce risk. Movement of individuals is affected by interactions with other people and the physical environment. The interaction between people around the physical environment is a matter of concern in crowd dynamics and requires further study investigating human factors to support the reliability of pedestrian simulation models. This paper studies the effect of speed on the ways pedestrians respond to obstacle avoidance. This research completed an experiment in which a group of people were instructed to perform obstacle avoidance tasks at two levels of speed—normal and high—by using different density levels and obstacle to investigate their crowd behaviour. The participants’ trajectories were extracted from video recordings to determine the effect of speed on the movement direction (x) axis and the lateral diversion (y) axis. The results revealed that different obstacle sizes did not affect the participants moving at normal speed but did affect the participants in the high-speed experiments. The results of these experiments could be used to enhance the current pedestrian simulation models.
Exposure to Pedestrian Crash Based on Household Survey Data: Safety Effect of Trip Purpose
Junbiao SU, Hong Kong Polytechnic UniversityShow Abstract
N.N. Sze, The Hong Kong Polytechnic Universtiy
Lu Bai, Southeast University
Pedestrian are vulnerable to severe injury and mortality in the road crashes. Better understanding the essence of pedestrian-vehicle crash is important to the development of safety countermeasures and improvement of social well-being. It is necessary to measure the exposure for the quantification of pedestrian crash risk. The primary goal of this study is to explore the exposure to pedestrian crash at the zonal level and identify the factors which affected the frequency of pedestrian crash at the zonal level. Walking trip frequency and trip time were applied to represent the exposure to pedestrian crash. Data were collected from the official database in Hong Kong during the period from 2011 to 2015. Three random-parameter negative binormial regression models in which the exposure was represented by aggregate walking trip frequency, the walking frequency by purpose and the walking frequency by purpose, respectively, were compared. It was found that the model in which the exposure was represented by the walking frequency by purpose provided the best goodness-of-fit. The factors which significantly affected the frequency of pedestrian crash at the zonal level included the walking trip frequency of different trip purposes, the number of non-signalized intersections, the number of zebra crossings, the proportions of children and elderly people, the propotions of people with degree, the proportions of the household with more than three members and road density. The findings of this study can help traffic engineers take effective traffic management measures to inprove pedestrian safety at the zonal level.
Pedestrian Red Light Running in Costa Rica: Exploring Factors Affecting Mid-Block Crossing Behavior
Enoc Araya-Porras, SediCon A.S.Show Abstract
Andrey Mora-Calderón, Constructora Hernán Solís S.R.L
Jonathan Aguero-Valverde, University of Costa Rica
Pedestrians are the most vulnerable road users and analyzing their behavior is necessary to provide infrastructure facilities that improve their mobility and safety. Mid-block pedestrian crossings are structures that facilitate the mobility of pedestrians, safeguarding them from vehicular traffic; however, illegal crossing by pedestrians is an everyday occurrence and represents a risk to their safety. The objective of this study is to evaluate the relationship between different human and road factors and the decision to illegally cross a signalized mid-block crossing. Several factors human factors such as age, gender, waiting time in traffic light, use of the pushbutton and individual or group crossing, as well as road characteristics such as the time of each traffic light phase, length of crossing, and vehicular volume were analyzed. To collect information about these variables this paper records a one-hour video in six selected crosswalks within the Montes de Oca County in Costa Rica. A total of 1,707 crossings were recorded, 10.6% of which corresponded to instances of illegal crossing. After applying a logit model this research found that traffic flow, red traffic light time, waiting time, vehicle illegal crossing and group crossings reduced the probability of violations by pedestrians. On the other hand, minimum traffic light time and crossing length increased the possibility of pedestrian illegal crossings. This study concluded that the traffic light cycle is an important variable that must be rigorously analyzed in order to ensure pedestrian's compliance with traffic lights; which will improve the safety of the pedestrian mid-block crossings.
A Pedestrian Crash Prediction Model for Urban Signalized Intersections Case Study: The City of Isfahan
Bahador Ghadirifaraz, Sharif University of TechnologyShow Abstract
Mohammad Nader Fotoohi, Isfahan Municipality
Manouchehr Vaziri, Sharif University of Technology
Ehsan Beheshtitabar, Old Dominion University
In this paper, in order to develop and validate a model of vehicle-pedestrian prediction crashes at urban intersections, data are gathered and extracted for 212 crashes at 55 signalized intersections of the city of Isfahan for four years period (2013-2016). While the total number of crashes within 50 m of each intersection was considered as the dependent variable, road network characteristics, land use characteristics, demographic and socio-economic characteristics within 400 m of each the intersection were considered as explanatory variables. The correlation test was performed to diagnose a possible multi-collinearity between variables t to eliminate variables which were correlated to each other. To model the frequency prediction of pedestrian crashes, a generalized linear model based on the negative binomial distribution was developed and validated. The results indicates that the number of legs, the average number of lanes at the intersection, total residing people, and land use characteristics within 400 m of the intersection type have a positive impacts on the number of pedestrian crashes. Conversely, the number of pedestrian crashes decrease with an increase in the pedestrian volume, the presence of safe pedestrian marked crosswalks, and public transport stops. Moreover, in addition to predicting the number of pedestrian crashes, this study can be useful since it provides insights for a better transportation policy-making and planning as well as engineering improvements to minimize pedestrian crashes in the city of Isfahan.
Modeling Transition States of Drivers During Yielding Right-of-Way at Signalized Mid-Block Crosswalks Using Hazard-Based Multi-State Model
Boniphace Kutela, University of Nevada, Las VegasShow Abstract
Hualiang Teng, University of Nevada, Las Vegas
This study presents an analysis of transition states during drivers’ yielding right-of-way to pedestrians at signalized midblock crosswalks. The study utilizes data from twenty signalized midblock crosswalks located in Las Vegas, Nevada, equipped with Traffic Control Signals (TCSs), Pedestrians Hybrid Beacons (PHBs), Circular Flashing Beacons (CFBs), Circular Rapid Flashing Beacons (CRFBs), and Rectangular Rapid Flashing Beacons (RRFBs). It applies both descriptive analysis and multistate models to explore the variations in transition durations and factors associated with the transition states of drivers’ yielding right-of-way, namely non-yield, multiple-threat, and full yield. The study found that the RRFBs are the signal types that have a high frequency of multiple-threat state. The duration to reach full yield varies between zero and 318 seconds; non-yield to multiple-threats duration varies between one and 105 seconds; while multiple-threat to full yield duration varies between one and 38 seconds. The multistate model results show that only signal type factor has a clear pattern. For this factor, the RRFBs showed low hazard ratios for all three transitions when compared to CFBs and CRFBs. In various ways, the states’ transition durations were also associated with number of cross stages, number of lanes, vehicle density, incoming vehicle speeds, Annual Average Daily Traffic (AADT), and number of pedestrians crossing, as well as their crossing positions. The developed model can be used by engineers and planners to evaluate factors affecting the effectiveness of the crosswalk treatments.