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This paper firstly show that 2 Dimensional Intelligent Driver Model (Jiang et al., 2014) is not able to replicate the synchronized traffic flow. Then we propose an improved model by considering the difference between the driving behaviors at high speeds and that at low speeds, which is in the framework of three-phase traffic theory. Simulations show that the improved model can reproduce the phase transition from synchronized flow to wide moving jams, the spatiotemporal patterns of traffic flow induced by traffic bottleneck, and the concave growth pattern of traffic oscillations (i.e. the standard deviation of the velocities of vehicles increases in a concave/linear way along the platoon). Validating results show that the empirical time series of traffic speed obtained from Floating Car Data can be well simulated as well. [ABSTRACT FROM AUTHOR]

The growing proportion of older drivers in the population plays an increasingly relevant role in road traffic that is currently awaiting the introduction of automated vehicles. In this study, it was investigated how older drivers (⩾60 years) compared to younger drivers (⩽28 years) perform in a critical traffic event when driving highly automated. Conditions of the take-over situation were manipulated by adding a verbal non-driving task (20 questions task) and by variation of traffic density. Two age groups consisting of 36 younger and 36 older drivers drove either with or without a non-driving task on a six-lane highway. They encountered three situations with either no, medium or high traffic density where they had to regain vehicle control and evade an obstacle on the road. Older drivers reacted as fast as younger drivers, however, they differed in their modus operandi as they braked more often and more strongly and maintained a higher time-to-collision (TTC). Deterioration of take-over time and quality caused by increased traffic density and engagement in a non-driving task was on the same level for both age groups. Independent of the traffic density, there was a learning effect for both younger and older drivers in a way that the take-over time decreased, minimum TTC increased and maximum lateral acceleration decreased between the first and the last situation of the experiment. Results highlight that older drivers are able to solve critical traffic events as well as younger drivers, yet their modus operandi differs. Nevertheless, both age groups adapt to the experience of take-over situations in the same way. [ABSTRACT FROM AUTHOR]

Variable speed limits (VSL) are used more commonly around the globe lately. Although on a macroscopic level positive effects of VSLs have been reported, the caveat is that the impact of VSLs is very sensitive to the level of driver compliance. Thus far it is unknown whether all individual drivers are actually able to notice when a speed limit changes into another speed limit; a prerequisite for purposeful speed limit compliance in the first place. To simulate regular driving conditions, twenty-four participants were familiarised with a particular route by driving the same route in a driving simulator nineteen times on five separate days. Part of the route consisted of a motorway where VSL signs were regularly displayed above every driving lane. At drive nineteen, speed limits changed from 80 km/h to 100 km/h on four out of eight consecutive signs. After passing all signs, one expects 6.25% of the participants still to be unaware that the speed limit had increased (based on chance), while the results showed most participants had failed to notice the speed limit change (58.3%). Instead, they saw what they expected to see: a speed limit of 80 km/h. If the speed change had been vice versa, in other words from 100 km/h to 80 km/h, this would immediately result in speed offences, though not deliberately at all. [ABSTRACT FROM AUTHOR]

The effects of imagery-induced distraction on hazard perception and eye movements were investigated in 2 simulated driving experiments. Experiment 1: sixty participants viewed and responded to 2 driving films containing hazards. Group 1 completed the task without distraction; group 2 completed a concurrent imagery inducing telephone task; group 3 completed a non imagery inducing telephone task. Experiment 2: eye-tracking data were collected from forty-six participants while they reacted to hazards presented in 16 films of driving scenes. 8 films contained hazards presented in either central or peripheral vision and 8 contained no hazards. Half of the participants performed a concurrent imagery-inducing task. Compared to undistracted participants, dual-taskers were slower to respond to hazards; detected fewer hazards; committed more “looked but failed to see” errors; and demonstrated “visual tunnelling”. Telephone conversations may interfere with driving performance because the two tasks compete for similar processing resources, due to the imagery-evoking aspects of phone use. [ABSTRACT FROM AUTHOR]

Research has paid little attention to driving and road safety in the ultraorthodox communities in Israel, in which perceptions on such issues display unique cultural characteristics, and may have long-term effects on traffic safety. This study attempts to gain insight into the attitudes and behaviors of the ultraorthodox young men road users in Israel with regard to driving and road safety, using a qualitative research method based on 42 face-to-face in-depth interviews with men from different ultraorthodox circles in different stages of life. The analysis reveals that the stringent cultural norms strongly influence road behavior, far beyond what is known about young novice drivers and their peers in general. For example, owning a license by young, single ultraorthodox students is seen as an offense against the ultraorthodox establishment compared to driving without a license, which is considered a one-time lapse. The findings indicate that unique cultural phenomena such as concealing the process of licensing, unlicensed driving and road interactions create a dangerous effect extending beyond the ultraorthodox neighborhoods. They also imply that road safety can be interpreted differently in diverse cultures, a fact which should be considered while planning safety intervention strategies. [ABSTRACT FROM AUTHOR]

Background The overrepresentation of young drivers in road crashes, injuries and fatalities around the world has resulted in a breadth of injury prevention efforts including education, enforcement, engineering, and exposure control. Despite multifaceted intervention, the young driver problem remains a challenge for injury prevention researchers, practitioners and policy-makers. The intractable nature of young driver crash risks suggests that a deeper understanding of their car use – that is, the purpose of their driving – is required to inform the design of more effective young driver countermeasures. Aims This research examined the driving purpose reported by young drivers, including the relationship with self-reported risky driving behaviours including offences. Methods Young drivers with a Learner or Provisional licence participated in three online surveys ( N 1 = 656, 17–20 years; N 2 = 1051, 17–20 years; N 3 = 351, 17–21 years) as part of a larger state-wide project in Queensland, Australia. Results A driving purpose scale was developed (the PsychoSocial Purpose Driving Scale, PSPDS), revealing that young drivers drove for psychosocial reasons such as for a sense of freedom and to feel independent. Drivers who reported the greatest psychosocial purpose for driving were more likely to be male and to report more risky driving behaviours such as speeding. Drivers who deliberately avoided on-road police presence and reported a prior driving-related offence had significantly greater PSPDS scores, and higher reporting of psychosocial driving purposes was found over time as drivers transitioned from the supervised Learner licence phase to the independent Provisional (intermediate) licence phase. Discussion and conclusions The psychosocial needs met by driving suggest that effective intervention to prevent young driver injury requires further consideration of their driving purpose. Enforcement, education, and engineering efforts which consider the psychosocial purpose of the driving are likely to be more efficacious than those which presently do not. Road safety countermeasures could reduce the young driver’s exposure to risk through such mechanisms as encouraging the use of public transport. [ABSTRACT FROM AUTHOR]

Driver cognitions about aggressive driving of others are potentially important to the development of evidence-based interventions. Previous research has suggested that perceptions that other drivers are intentionally aggressive may influence recipient driver anger and subsequent aggressive responses. Accordingly, recent research on aggressive driving has attempted to distinguish between intentional and unintentional motives in relation to problem driving behaviours. This study assessed driver cognitive responses to common potentially provocative hypothetical driving scenarios to explore the role of attributions in driver aggression. A convenience sample of 315 general drivers 16–64 yrs ( M = 34) completed a survey measuring trait aggression (Aggression Questionnaire AQ), driving anger (Driving Anger Scale, DAS), and a proxy measure of aggressive driving behaviour (Australian Propensity for Angry Driving AusPADS). Purpose designed items asked for drivers’ ‘most likely’ thought in response to AusPADS scenarios. Response options were equivalent to causal attributions about the other driver. Patterns in endorsements of attribution responses to the scenarios suggested that drivers tended to adopt a particular perception of the driving of others regardless of the depicted circumstances: a driving attributional style. No gender or age differences were found for attributional style. Significant differences were detected between attributional styles for driving anger and endorsement of aggressive responses to driving situations. Drivers who attributed the on-road event to the other being an incompetent or dangerous driver had significantly higher driving anger scores and endorsed significantly more aggressive driving responses than those drivers who attributed other driver’s behaviour to mistakes. In contrast, drivers who gave others the ‘benefit of the doubt’ endorsed significantly less aggressive driving responses than either of these other two groups, suggesting that this style is protective. [ABSTRACT FROM AUTHOR]

Hazard perception (HP) is a driving skill and is described as drivers' ability to 'read' the road and anticipate hazardous events. Typically, exploring differences in HP abilities between experienced and young-inexperienced drivers involves a paradigm in which drivers observe short traffic-scene movies and press a response button each time they identify a hazard. The time measured from when the hazard is detectable up to when the driver pressed the response button is labeled response time. While some studies revealed that experienced drivers detect hazards faster than less experienced drivers, other studies did not report any differences. The current study suggests a possible explanation for this apparent contradiction by arguing that the way response time data are analyzed differs across studies and may lead to different conclusions. Specifically, it is argued that common practices fail to manage cases where a participant did not respond to a hazard, usually by replacing it with the mean response time or any other central tendency parameter. The current study proposes survival analysis as a more suitable methodology for analyzing response time in the HP realm. Survival analysis was compared to other commonly used methods on the basis of their ability to estimate the actual distribution from where response time data were generated. Both simulation of pre-defined distributions and real-world data revealed that commonly used methods underestimate the real distribution whereas survival analysis technique accurately estimates its values. The implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

It has long been presumed that drivers' perceptions of risk play an important role in guiding on-road behaviour. The answer to how accurately drivers perceive the momentary risk of a driving situation, however, is unknown. This research compared drivers' perceptions of the momentary risk for a range of roads to the objective risk associated with those roads. Videos of rural roads, filmed from the drivers' perspective, were presented to 69 participants seated in a driving simulator while they indicated the momentary levels of risk they were experiencing by moving a risk meter mounted on the steering wheel. Estimates of the objective levels of risk for the roads were calculated using road protection scores from the KiwiRAP database (part of the International Road Assessment Programme). Subsequently, the participants also provided risk estimates for still photos taken from the videos. Another group of 10 participants viewed the videos and photos while their eye movements and fixations were recorded. In a third experiment, 14 participants drove a subset of the roads in a car while providing risk ratings at selected points of interest. Results showed a high degree of consistency across the different methods. Certain road situations were rated as being riskier than the objective risk, and perhaps more importantly, the risk of other situations was significantly under-rated. Horizontal curves and narrow lanes were associated with over-rated risk estimates, while intersections and roadside hazards such as narrow road shoulders, power poles and ditches were significantly under-rated. Analysis of eye movements indicated that drivers did not fixate these features and that the spread of fixations, pupil size and eye blinks were significantly correlated with the risk ratings. An analysis of the road design elements at 77 locations in the video revealed five road characteristics that predicted nearly 80% of the variance in drivers' risk perceptions; horizontal curvature, lane and shoulder width, gradient, and the presence of median barriers. [ABSTRACT FROM AUTHOR]

Highlights: [•] Complex response irrelevant stimuli, frequently encountered in traffic can influence responses via hands and via foot pedals. [•] Reactivation of former responses also affects performance in situations that require response restraint. [•] The effect of response retrieval affects responses in driving situations. [Copyright &y& Elsevier]

Highlights: [•] We studied driver glance behaviour with intermittent and continuous eco-driving advice. [•] The research platform was a high-fidelity truck simulator with linear motion. [•] Continuous displays lead to a steadily increased glance frequency and duration. [•] Intermittent displays lead to high glance activity when information is presented. [•] Drivers consider the traffic demands before looking at an intermittent display. [Copyright &y& Elsevier]

Highlights: [•] Systematic manipulation of dynamic traffic complexity in a driving simulator study. [•] Workload fluctuations were assessed using subjective and performance measures. [•] Driver workload varies linearly with traffic flow up to moderate levels. [•] Presence of lane changes in surrounding influence workload and driving performance. [Copyright &y& Elsevier]

Highlights: [•] A new driver assistance system is realized by a Markov Decision Process. [•] Its warning and intervention strategies are estimated from human behavior traces. [•] A human driver is modeled by the composition of Dynamic Bayesian Networks. [•] The action-relevant percepts of the model are estimated from human behavior traces. [•] The model is able to reproduce the longitudinal driving behavior of human drivers. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate the benefits of text and symbolic displays in highway signs relative to their familiarity on their comprehension speed and accuracy. Background: A recent study that evaluated the influence of ergonomic principles – familiarity, standardization, and symbol-concept compatibility – on traffic sign comprehension showed that comprehension is highly correlated with the compliance with these ergonomic design principles (Ben-Bassat & Shinar, 2006). As an alternative to existing unfamiliar symbolic signs we tested the effect of adding text. Method: Drivers were presented with 30 traffic signs varying in their level of familiarity in three display conditions: standard symbol-only, text-only, and symbol+text. Speed and accuracy of comprehension were recorded. Results: Display condition and familiarity significantly affected both correctness of the answers and reaction time. Correctness improved when the symbol was shown with text, especially when the sign was less familiar. Conclusions: Adding text improves the comprehension and reduces the time it takes to comprehend the sign, especially of unfamiliar signs. Application: Adding text could be a simple solution to making (unfamiliar) signs more understandable to a greater segment of the driving population without compromising comprehension time, thereby increasing traffic safety. [Copyright &y& Elsevier]

Abstract: Previous research has indicated that older drivers are more likely to be involved in collisions in complex traffic scenarios like intersections even if they are not more involved in accidents in general. Moreover, being more vulnerable, the older driver is generally at higher risk of sustaining an injury when involved in a traffic accident. Even though there may be many factors leading to the over-involvement of older drivers in intersection collisions it is clear that the visual capacity and the ability to observe may be one of the possible causes that is of high interest to understand further. The objective of the study is to identify to what degree the visual behaviour could explain older drivers’ involvement in intersection accidents. A 20km long route composed by intersections in rural and urban environment was selected to collect both driving and eye movement data. Two groups of drivers were compared, one group aged 35–55years and one aged 75 and above. Apart from the driving data, neck flexibility measurement was performed. The results from the neck flexibility measurement showed a clear age effect, with the older drivers showing less neck flexibility. When it comes to visual behaviour data, a difference was also found concerning the area of interest the drivers looked at; while the older drivers looked more at lines and markings on the road to position themselves in the traffic, the younger drivers looked more at dynamic objects such as other cars representing a possible threat. The difference in the visual behaviour should be used to design safety systems for all drivers to support them when they drive through an intersection. [Copyright &y& Elsevier]

Abstract: A perfectly adequate traffic rule can turn “perverse” in situations when it does little to enhance road safety but seems – at least in the drivers’ minds – directed primarily at punishing those who violate it. This study examined traffic rule obedience in situations in which the rule was not in accordance with real safety needs. Six rules with major impact on road safety were analyzed: waiting at red traffic lights, legal overtaking, obeying the 50km/h speed limit, wearing seatbelts, legal stopping/parking, and driving the car in good technical condition. Participants evaluated how adequate these rules are for safety. Then they were faced with six scenarios, that made each of these rules appear irrational, and were asked to report their potential engagement in deviant behavior. The survey data were collected in a sample of 605 drivers. Multiple regression analyses showed that in most situations rule violation depended on the usual deviant behavior, perceived irrationality of the rule, little respect for the law and low risk perception. These factors best explained the 50km/h speed limit violation. The results suggest that the lack of situational risk factors, which makes the rule look meaningless, is important determinant of rule violation. Implications for massive disobedience and road safety are discussed. [Copyright &y& Elsevier]

Abstract: How should we assess the comparability of driving on a road and “driving” in a simulator? If similar patterns of behaviour are observed, with similar differences between individuals, then we can conclude that driving in the simulator will deliver representative results and the advantages of simulators (controlled environments, hazardous situations) can be appreciated. To evaluate a driving simulator here we compare hazard detection while driving on roads, while watching short film clips recorded from a vehicle moving through traffic, and while driving through a simulated city in a fully instrumented fixed-base simulator with a 90 degree forward view (plus mirrors) that is under the speed/direction control of the driver. In all three situations we find increased scanning by more experienced and especially professional drivers, and earlier eye fixations on hazardous objects for experienced drivers. This comparability encourages the use of simulators in drivers training and testing. [Copyright &y& Elsevier]

Abstract: When drivers are approaching a signalized intersection at the onset of yellow signal, they may hesitate to decide whether to stop or cross the intersection due to the dilemma zone. As defined in the Traffic Engineering Handbook [Institute of Transportation Engineers (ITE). (1999). Traffic engineering handbook, Washington, DC: Institute of Transportation Engineers], the dilemma zone for an intersection is a specific road segment, prior to the intersection in which a vehicle approaching the intersection during the yellow phase can neither safely clear the intersection, nor stop comfortably at the stop line. In this study, a pavement marking countermeasure is proposed to reduce the dilemma zone and improve traffic safety at signalized intersections. A pavement marking with word message ‘Signal Ahead’ that is placed on the pavement upstream of a signalized intersection may have a potential to assist drivers in stop/go decisions and improve driver performance during the signal change. This paper presents a simulator-based study that was designed to test the impact of the pavement marking countermeasure on driving behaviors, including driver’s stop/go decision, red-light running violation, brake response time, and deceleration rate of the stopping vehicle. The experiment results indicated that the marking had positive effects on drivers’ behaviors at signalized intersections. It was found that the marking can reduce the probabilities of both conservative-stop and risky-go decisions, contribute to a lower red-light running rate, and result in a lower deceleration rate for stopping drivers at higher speed limit intersections. These findings suggest that the marking countermeasure may have a potential to reduce the probabilities of both rear-end and angle crashes. [Copyright &y& Elsevier]

Abstract: The growth in motorised traffic on rural lanes in the UK has increased the dangers of, and dissuades people from, walking, cycling or horse riding on roads in the countryside. A UK Government initiative, “Quiet Lanes”, aims to address this contra-sustainability development and make rural lanes safe and attractive for non-motorised users. Although traffic calming measures have been employed in urban areas, their translation into more environmentally sensitive rural areas has been problematic, largely on aesthetic grounds as they often have an urban appearance. Innovative solutions are necessary to reduce traffic speed but it would be prudent to assess experimentally the likely effectiveness and acceptability of any new measures before they are built. This paper discusses the use of simulated environments by means of manipulated colour photographs to predict changes in driving behaviour associated with changing road environments. It was found that respondents were able to differentiate between the different simulated engineering solutions and their suggested driving behaviour accurately reflected that associated with road use under similar conditions elsewhere. [Copyright &y& Elsevier]