Structural equation modelling of potential risk factors for pedestrian accidents in rural and urban roads

Senior Americans' perceptions, attitudes, and safety concerns toward Autonomous Vehicles (AVs)

INTRODUCTION

Autonomous vehicles (AVs) are considered a promising solution to improve seniors' safety and mobility. However, to transition to fully automated transportation, especially among seniors, it is vital to assess their perception and attitude toward AVs. This paper investigates seniors' perceptions and attitudes to a wide range of AV options from the perspective of pedestrians and users in general, as well as during and after the COVID-19 pandemic. Underlying this objective is to examine older pedestrians' safety perceptions and behaviors at crosswalks in the presence of AVs.

METHOD

A national survey collected data from a sample of 1,000 senior Americans. Using Principal Component Analysis (PCA) and Cluster Analysis, three clusters of seniors were identified with different demographic characteristics, perceptions, and attitudes toward AVs.

RESULTS

PCA findings revealed that "risky pedestrian crossing behavior," "cautious pedestrian crossing behavior in the presence of AVs," "positive perception and attitude toward shared AVs," and "demographic characteristics" were the main components explaining most of the variation within the data, respectively. The PCA factor scores were used in the cluster analysis, which resulted in the identification of three distinctive groups of seniors. Cluster one included individuals with lower demographic scores and a negative perception and attitude toward AVs from the perspective of users and pedestrians. Clusters two and three included individuals with higher demographic scores. Cluster two included individuals with a positive perception toward shared AVs from the user perspective, but a negative attitude toward pedestrian-AV interaction. Cluster three included those with a negative perception toward shared AVs but a somewhat positive attitude toward pedestrian-AV interaction. The findings of this study provide valuable insights to transportation authorities, AV manufacturers, and researchers regarding older American's perception and attitude toward AVs as well as their willingness to pay and use Advanced Vehicle Technologies.

Road safety assessment and risks prioritization using an integrated SWARA and MARCOS approach under spherical fuzzy environment

There are a lot of elements that make road safety assessment situations unpredictable and hard to understand. This could put people's lives in danger, hurt the mental health of a society, and cause permanent financial and human losses. Due to the ambiguity and uncertainty of the risk assessment process, a multi-criteria decision-making technique for dealing with complex systems that involves choosing one of many options is an important strategy of assessing road safety. In this study, an integrated stepwise weight assessment ratio analysis (SWARA) with measurement of alternatives and ranking according to compromise solution (MARCOS) approach under a spherical fuzzy (SF) set was considered. Then, the proposed methodology was applied to develop the approach of failure mode and effect analysis (FMEA) for rural roads in Cosenza, southern Italy. Also, the results of modified FMEA by SF-SWARA-MARCOS were compared with the results of conventional FMEA. The risk score results demonstrated that the source of risk (human) plays a significant role in crashes compared to other sources of risk. The two risks, including landslides and floods, had the lowest values among the factors affecting rural road safety in Calabria, respectively. The correlation between scenario outcomes and main ranking orders in weight values was also investigated. This study was done in line with the goals of sustainable development and the goal of sustainable mobility, which was to find risks and lower the number of accidents on the road. As a result, it is thus essential to reconsider laws and measures necessary to reduce human risks on the regional road network of Calabria to improve road safety.

Investigating speed-safety association: Considering the unobserved heterogeneity and human factors mediation effects

The relationship between mean speed and crash likelihood is unclear in the literature. The contradictory findings can be attributed to the masking effects of the confounding variables in this association. Moreover, the unobserved heterogeneity has almost been criticized as a reason behind the current inconclusive results. This research provides an effort to develop a model that analyzes the mean speed-crash frequency relationship by crash severity and type. Also, the confounding and mediation effects of the environment, driver, and traffic-related attributes have been considered. To this end, the loop detector and crash data were aggregated daily for rural multilane highways of Tehran province, Iran, covering two years, 2020-2021. The partial least squares path modeling (PLS-PM) was employed for crash causal analysis along with the finite mixture partial least squares (FIMIX-PLS) segmentation to account for potential unobserved heterogeneity between observations. The mean speed was negatively and positively associated with the frequency of property damage-only (PDO) and severe accidents, respectively. Moreover, driver-related variables, including tailgating, distracted driving, and speeding, played key mediation roles in associating traffic and environmental factors with the crash risk. The higher the mean speed and the lower the traffic volume, the higher odds of distracted driving. Distracted driving was, in turn, associated with the higher vulnerable road users (VRU) accidents and single-vehicle accidents, triggering a higher frequency of severe accidents. Moreover, lower mean speed and higher traffic volume were positively correlated with the percentage of tailgating violations, which, in turn, predicted multi-vehicle accidents as the main predictor of PDO crash frequency. In conclusion, the mean speed effects on the crash risk are entirely different for each crash type through distinct crash mechanisms. Hence, the distinct distribution of crash types in different datasets might have led to current inconsistent results in the literature.

Structural equation modeling of pedestrian behavior at footbridges in Ghana

This study was undertaken to fill the information gap by exploring pedestrian behavior at footbridges in the Greater Accra and Kumasi Metropolitan areas of Ghana. Further, the study modelled the behavior of 69,840 pedestrians at the footbridges using Structural Equation Modeling (SEM). Pedestrians were observed as users and non-users of seven selected footbridges in the morning (7:00 am-9:00 am), afternoon (11:00 am-1:00 pm), and evening (3:00 pm-5:00 pm) periods for seven consecutive days (Monday to Sunday). Selected footbridges were characterized by traffic generators as schools, shopping malls, bus stops, office complexes, and restaurants in different matrices. The results showed that 30.7% of the observed pedestrians did not use the footbridges, males and young pedestrians were more likely not to use the footbridges as opposed to females and the elderly with more than half of observed pedestrians carrying luggage or load. Footbridge users were more likely to talk and hold phones than non-users and the elderly were more likely to run and ride compared to young pedestrians. Officials of the National Road Safety Authority should carry out effective public education on pedestrian safety targeting males and young pedestrians to encourage the use of pedestrian footbridges.

An integrated text mining, literature review, and meta-analysis approach to investigate pedestrian violation behaviours

The goal of this study is to provide an overview of previous research that investigated pedestrian violation behaviour, with a focus on identifying the contributing factors of such behaviour, its impact on pedestrian safety, the mitigation strategies, the limitations of current studies, and the future research directions. To that end, the Latent Dirichlet Allocation (LDA) text mining method was applied to extract a comprehensive list of studies that were conducted during the past 21 years related to pedestrian violation behaviours. Using the extracted studies, a multi-sectional literature review was developed to provide a comprehensive understanding of the different aspects related to pedestrian violations. Afterward, a meta-analysis was undertaken, using the studies that reported quantitative results, in order to obtain the average impact of the different contributing factors on the frequency of pedestrian violations. The study found that pedestrian violations are one of the hazardous behaviours that contribute to both the frequency and severity of pedestrian-vehicle collisions. According to the literature, the waiting time at the curbside, traffic volume, walking speed, pedestrian distraction, the presence of bus stops and schools, and the presence of on-street parking are among the key factors that increase the likelihood of pedestrian violations. The study has also reviewed a wide range of strategies that can be used to mitigate violations and reduce the safety consequences of such behaviour, including simple engineering-based countermeasures, enforcement, solutions that rely on advanced in-vehicle technologies, and infrastructure connectivity features, educational programs, and public campaigns.

Proactive pedestrian safety evaluation at urban road network level, an experience in Kolkata City, India

In developing nations, road traffic crashes involving pedestrians have become a foremost worry. Presently, most of the road safety assessment projects and selection of interventions are still restricted to traditional methods that depend on historical crash data. However, in low and middle-income countries such as India, the availability, reliability, and accuracy of crash data are uncertain. Alternatively, Post Encroachment Time (PET) has added attention as a proximal indicator to examine pedestrian-vehicular potential crashes and address pedestrian risk under mixed traffic conditions. Hence, it will be meaningful to examine if the PET is a good substitute for pedestrian-vehicular crashes and if so, what built environment and pedestrian-level factors influence PET. In this background, the present study establishes a mathematical association between the average PET value of the urban road network level and actual crashes. Afterward, multiple linear regression models are developed to study the impact of the built environment, traffic parameters, and pedestrian-level attributes on PET. The outcomes indicate that vehicle speed, lack of enforcement, absence of traffic signal (for traffic as well as pedestrians), land use type, slum population, inadequate sight distance, pedestrian's state of crossing, and pedestrian's risky crossing behaviour substantially affect the average PET at road network-level.

Analyzing traffic violations among motorcyclists using structural equation modeling

In developing countries, the motorcycle is one of the main modes of transportation, especially in the downtown area. Motorcyclists' safety is a common issue since they have more vulnerability for severe crashes. Thus, it is necessary to decrease the probability of encountering high-risk situations. The main reason for motorcycle crashes is human errors in the form of traffic violations. This article aims to identify the role of seven factors on traffic violations, including motorcyclist characteristics, road conditions, environmental circumstances, riding skills, cycling statuses, motorcycle age and previous negative experiences such as fines and accidents. The structural equation modeling was applied to evaluate the impact of these factors pertinent to motorcyclists' crashes. To assess these factors, 600 motorcyclists have been interviewed in Kerman, Iran. The results indicated that motorcyclists' characteristics are the most effective factor in violation commitment. Since most motorcyclists are young, with low income and education, it is necessary to pay more attention to their training and education before giving a cycling license. In addition, those with more previous crashes and violations are more susceptible to committing violations. This relates to the lack of enough control and enforcement in developing cities; also, it shows that the current traffic fines are not deterrent enough. Finally, considering the results of this research can help to minimize traffic violations among motorcyclists, which is a step towards safer roads.

Safety Climate and Productivity Improvement of Construction Workplaces Through 6S System: Mixed-Method Analysis of 5S and Safety Integration

The purpose of this study is to develop a framework for integrating essential safety practices (visualization, job safety analysis, and plan-do-check-act) into 5S steps and validate it. First, 18 interviews with a snowball sample of construction workers, safety representatives, supervisors, site and project managers were conducted. A grounded theory method was utilized to code the interview data. The results revealed that studied construction companies implement a systematic safety-based methodology to minimize construction work injuries. Second, to validate the proposed framework, a pre- and post-test study was applied. The case and control groups (26 participants) answered a 6S questionnaire before the 6S system and one month after it. The results revealed that safety climate and productivity significantly increased for the case group but reduced for the control group during time.