Drivers’ driving style and their take-over-control judgment

Advanced driver assistance systems (ADASs), which help a driver drive a car safely and easily (e.g., warning alerts, steering control, and brake/acceleration pedal operation), have increased in popularity. However, such systems have not yet been perfected. Sometimes, humans must take over control from the systems; otherwise, they can cause an accident. In this study, we focused on one of the ADASs, adaptive cruise control (ACC), which automatically maintains a selected distance from the preceding car, and investigated individual differences in take-over-control judgment and related factors. The candidate factors included driver’s manual driving style, driving performance without the ACC, and the usability evaluation of ACC. Ten participants repeated the short, strictly controlled trials in a driving simulator (DS), with a varying value of only one parameter (deceleration of the preceding car) affecting the need for intervention. First, we confirmed that the participants made the judgment based on the dangerousness of the situation and that there were individual differences in the take-over-control judgments. Some participants intervened in the ACC control in less dangerous trials, whereas other participants did not, even if their own car got very close to the preceding car. We conducted a correlation analysis and confirmed the results with the estimation of the confidence interval using a bootstrap method. As a result, we found that driving style and driving performance without ACC had a stronger relationship to the number of interventions, rather than the usability evaluation. In particular, methodical drivers, who obeyed traffic rules and manners, began to intervene in less dangerous situations. The tendency to avoid utilizing brake operations was also related to take-over-control judgment. This might be because the participants intervened by pressing the brake pedal. Our study showed that drivers’ driving style could affect the usage of ACC independently from the performance of the ACC.     

Professional and non-professional drivers’ stress reactions and risky driving

The aim of the present study was to investigate stress reactions, speeding, number of penalties and accident involvement among different driver groups (taxi drivers, minibus drivers, heavy vehicle drivers, and non-professional drivers). A total number of 234 male drivers participated in the study. The participants were asked to complete the Driver Stress Inventory (DSI) together with a demographic information form. Five dimensions of the DSI were measured; aggression, dislike of driving, hazard monitoring, fatigue proneness, and thrill-seeking. After controlling the effects of age and annual mileage, the results of the ANCOVAs revealed differences between different driver groups in terms of both risky driving behaviours and stress reactions in traffic. Regression analyses indicated that aggression, dislike of driving, and hazard monitoring dimensions of the DSI were related to accident involvement after controlling for the effects of age, annual mileage and driver group. Dislike of driving and thrill-seeking dimensions of the DSI were related to speeding on in-city roads.     

Effects of route familiarity on drivers’ psychological conditions: Based on driving behaviour and driving environment

Route familiarity affects a driver’s mental state and indirectly affects traffic safety; however, this important factor is easily overlooked. Previous research on route familiarity has only analysed psychological states in terms of unfamiliarity and familiarity, the influence of driving behaviour and driving environment on psychological states has been ignored. As a result, the mechanisms through which the route familiarity influence driver psychological states, and vice versa, are unclear. This study proposes a quantitative framework for studying driver psychological condition and route familiarity using experimental data from a real driving task and driving environment data. The experimental data included 1022 observations obtained by 23 participants over 7 consecutive trials on 6 unfamiliar experimental routes with large differences in scenarios; environmental data were automatically extracted after segmenting a driving video through the Dilated Residual NetWorks model. The results reveal that (1) the relationship between the driver’s psychological condition and route familiarity is not monotonic and is different for straight and turning sections; (2) the driver’s psychological condition is influenced by the visual scene elements and the type of road section, and the results of the multivariate regression analysis quantified the variability of the influence; and (3) unlike a majority of findings on distracted driving, our study suggest that the driver’s attention to the external environment in the urban distracted driving state will gradually approach a ‘distraction threshold’, and the time and size of the ‘distraction threshold’ are influenced by the driver. This study can further the development of urban traffic safety research and help urban designers plan and improve urban landscapes to ensure drivers maintain stable mental states when they drive.     

Drunk driving offenders’ knowledge and behaviour in relation to alcohol-involved driving in Yinchuan and a comparison with Guangzhou,China

ObjectiveThis study was conducted after a legislative amendment criminalising drunk driving (BAC > 80 mg/100 ml) had been in force for a year and investigated whether drunk driving offenders in Yinchuan, China were aware of the law, and whether their knowledge of and exposure to enforcement and the existence of alcohol use disorders were related to their alcohol-involved driving behaviour. The results were compared with results from an earlier study in Guangzhou, China.MethodA survey was conducted from July to October 2012 in Yinchuan to collect information on drunk driving offenders’ knowledge and practice in relation to alcohol-involved driving. The Alcohol Use Disorders Identification Test (AUDIT) was used to assess hazardous drinking levels. In total, 106 drunk driving offenders were recruited while in detention. The findings were compared with those of the Guangzhou study, where the same procedure was used to recruit 101 drunk driving offenders.ResultsThe mean age of the sample was 31.7 years (SD = 8.1; range 17–59 years). Males constituted 96% of the sample. The mean age at which offenders reported starting to drink alcohol was 18.7 years (SD = 3.2; range 10–26 years). Driver’s licenses had been held for an average of 8.5 years. The status of knowledge in relation to alcohol-involved driving in Yinchuan was slightly lower in proportion than in Guangzhou. The rate of alcohol-involved driving reported in the previous 12 months in Yinchuan (43%) was slightly higher than in Guangzhou (39%). The proportion of recidivists in Guangzhou (21.8%) was higher than Yinchuan’s (10.4%). On average, offenders had experienced 1.6 police alcohol breath tests in the previous year (SD = 1.3; range 1–10). AUDIT scores indicated that a substantial proportion of the offenders had high levels of alcohol use disorders.DiscussionLimited awareness of legal alcohol limits might contribute to drunk driving offences. The high level of alcohol consumption by many offenders suggests that hazardous drinking levels may be a contributor. Recidivist drivers also had higher AUDIT scores, which suggest there may be benefit in using the AUDIT to identify potential drink drivers and recidivists, subject to further research.     

Situational specificity of trait influences on drivers’ evaluations and driving behaviour

This study explored the influence of anger and anxiety traits on driver evaluations and behaviour during a simulated drive. Forty-eight licensed drivers completed identical simulated driving tasks during which they rated levels of current anger, calmness and frustration or levels of danger, calmness and difficulty. Anxiety-prone drivers made higher difficultly evaluations and generally drove more cautiously. Anger-prone drivers gave higher ratings of anger and frustration, but their evaluations and anger tendencies were unrelated to their general driving behaviours. When driving behaviours in high and low anger-provoking situations were contrasted, in low anger-provoking situations, drivers higher in trait anger reported more anger and frustration and also drove faster and with more sideward movement. When driving situations were considered separately, although not overall, behaviour and evaluations were related: when forced to move sideward, drivers reported more frustration; when forced to drive more slowly, they reported more anger, and subsequently increased acceleration, throttle pressure and steering wheel use. These relationships were not moderated by trait anger. Irrespective of trait anger, drivers become angry when impeded, or in other anger-provoking situations, only drivers with high trait anger become angry and behaved aggressively in circumstances most would not consider provocative.     

It’s all in the mind: The relationship between mindfulness and nomophobia on technology engagement while driving and aberrant driving behaviours

This study investigated the relationship between mindfulness and nomophobia on technology engagement while driving and aberrant driving behaviours. Nine hundred and ninety participants completed an online survey (Female: 68.6%; Age: M = 51.2 years, SD = 15.7, Range = 18.0–84.0 years) that assessed mindfulness, nomophobia, technology engagement while driving, aberrant driving behaviour, and self-reported crashes and infringements during the past two years. Structural equation modelling (SEM) was used to examine the relationships between mindfulness and nomophobia, on one hand, with self-reported engagement with technology while driving and general aberrant driving behaviours (combination of errors, lapses and violations) on the other. The results of the SEM showed that, as expected, mindfulness shared negative relationships with nomophobia, engagement with technology and aberrant driving behaviours, while all other relationships were positive. In terms of engagement with technology, there were direct and indirect paths between nomophobia and mindfulness and engagement with technology. The results of this study demonstrate the positive influence mindfulness can have on nomophobia, engagement with technology while driving, and dangerous driving behaviours that have been associated with crash risk. Mindfulness practices may reduce the effect of nomophobia on engagement with technology while driving and increased dangerous behaviours as a result. This will be increasingly important as modern work and social practices encourage people to increasingly use the phone while driving, and the technology within smart devices, and connectivity of these to the vehicle, increase. More research is needed to understand whether mindfulness-based interventions can reduce nomophobia, and thereby improve driving behaviours and reduce crash rates.     

Do aggressive driving and negative emotional driving mediate the link between impulsiveness and risky driving among young Italian drivers?

ABSTRACT

The present study examined the contribution of impulsiveness and aggressive and negative emotional driving to the prediction of traffic violations and accidents taking into account potential mediation effects. Three hundred and four young drivers completed self-report measures assessing impulsiveness, aggressive and negative emotional driving, driving violations, and accidents. Structural equation modeling was used to assess the direct and indirect effects of impulsiveness on violations and accidents among young drivers through aggressive and negative emotional driving. Impulsiveness only indirectly influenced drivers’ violations on the road via both the behavioral and emotional states of the driver. On the contrary, impulsiveness was neither directly nor indirectly associated with traffic accidents. Therefore, impulsiveness modulates young drivers’ behavioral and emotional states while driving, which in turn influences risky driving.     

Socio-economic and driving experience factors affecting drivers’ perceptions of traffic crash risk

Drivers are estimated to contribute an overwhelming proportion to the burden of traffic crashes, as factors that increase crash risk are frequently due to unsafe driving behaviours. The relationship between risk perceptions and people’s risky driving behaviours is still not well understood. This paper aims to further analyse the potential effect of risky driving behaviours on drivers’ perceptions of crash risk and differences in perceptions among drivers.Crash risk perceptions in an inter-city, two-way road context of 492 drivers were measured by using a Stated Preference (SP) ranking survey. Rank-ordered logit models were used to evaluate the impact on risk perception of five unsafe driving behaviours and to identify differences in drivers’ risk perceptions. The five unsafe driving behaviours considered in the analysis were respectively related to whether or not the driver follows the speed limits, the rules of passing another car and the safe distance, whether or not the driver is distracted, and whether or not she/he is driving under optimal personal conditions.All risky driving behaviours showed a significant potential effect (p < 0.001) on crash risk perceptions, and model’s results allowed to differentiate more important from less important unsafe driving behaviours based on their weight on perceived crash risk. Additionally, this paper further analyses the potential differences in risk perception of these traffic violations between drivers of different characteristics, such as driving experience, household size, income and gender.The SP technique could be applied to further analyse differences in perceptions of risky driving behaviours among drivers. Future research should consider the potential effect of driving skill on perceptions of risky driving behaviours.     

Older drivers’ self-assessed driving skills,driving-related stress and self-regulation in traffic

Previous research on older drivers has indicated connections between self-rated driving ability, confidence in their own driving, driving-related stress, and self-regulatory behaviour. However, more systematic associations between older drivers’ perceptions on their own driving and self-regulation or driver stress and self-regulation behaviour, and possible gender differences in these, have not been obtained in previous studies. The aim of the present study was to gain a better understanding of older drivers’ self-regulatory driving and the motivators behind this behaviour, by placing this behaviour in the modern traffic psychological framework of the driving task. 888 drivers aged 75 or older completed a structured phone interview about their perceived changes in driving skills, driving-related discomfort, and avoidance of driving situations. The results showed that when reporting change, the participants were more likely to report improvement of higher level skills and decline of the lowest level skills. Women were less likely to report improvement and more likely to report decline of skills. Driving situations related to inner states or adverse conditions were more often associated with discomfort and avoidance than situations related to infrastructure, and women were more likely to report discomfort and avoidance of driving situations. The results suggest that older drivers generally show good self-judgement of changes in their driving skills and acknowledge the different types of skills comprised in the driving task. The results also provide a better understanding of older drivers’ self-regulation of driving and gender differences in this, thus providing a better understanding in particular of women drivers’ self-regulation and increased risk of premature driving cessation. These findings may be valuable when encouraging older drivers, especially women, to prolong their driving.     

Who’s more angry? Comparing driver anger and aggression within work and personal driving contexts

Anger and driver aggression increase crash risk. However, how these manifest according to the purpose of the journey (work vs personal) and the unique relationships between sources of anger and aggressive expressions of that anger is under-researched. The current study examined the relationships between different types of anger and aggression, recent crashes and infringements between drivers who drive mainly for work with those who drive mainly for personal reasons.Participants (N = 630) completed an online questionnaire reporting their driving anger tendencies across situations of travel delays, danger and hostility from others, frequency of aggressive driving (using the vehicle, verbal or physical) and crash and infringements in the previous year. Drivers were classified as work or personal drivers based on the percentage of the time they drove for each reason. Relationships between anger sources and aggression types were examined using Structural Equation Modelling, comparing models between the two groups. The relationships between aggression and safety outcomes were explored using Mann-Whitney U tests.The relationships between anger and aggression were similar across work and personal drivers. However, some group differences in the situations that contributed to anger and aggression were identified. Aggression was more frequent for drivers who drove mainly for work and had received a traffic violation, compared to those who had not received a traffic violation.These findings can inform the development of targeted interventions to manage the triggers of anger and aggression. Interventions are likely to impact work and personal drivers; thus, could target employers and road transport authorities.     

Predicting pleasure at others’ misfortune: Morality trumps sociability and competence in driving deservingness and schadenfreude

Schadenfreude occurs when people feel pleasure at others’ misfortunes. Previous research suggested that individuals feel such a malicious pleasure when the misfortune befalls social targets perceived as highly competent but lacking human warmth. Two experiments explored whether the two components of warmth (i.e., sociability and morality) have distinct roles in driving schadenfreude. Study 1 (N = 128) compared a competent but immoral individual to a competent but unsociable person and found that people felt more schadenfreude when a misfortune befell an individual lacking morality. Study 2 (N = 199) confirmed the primary role of morality in driving schadenfreude by manipulating not only morality and sociability, but also competence. Moreover, both experiments showed that social targets lacking moral qualities elicited higher levels of schadenfreude because their misfortunes were perceived as deserved. Overall, our findings suggest that morality has a primary role over other basic dimensions of person perception (i.e., sociability and competence) in driving schadenfreude.     

Young male drivers’ risky driving 15 months after licensure – The role of intervention,attitudes towards accompanied driving,and parents’ risk

An indispensable issue in contemporary research on risk-taking by young drivers is parents’ influence on their offspring’s driving behavior. The current study measures this influence by using a risk index of parents’ driving behavior measured via in-vehicle data recorders together with young drivers’ self-reported answers to a set of questionnaires. Both parents and young drivers participated in one of three intervention program groups to enhance safe driving within a longitudinal study, and the outcome of this intervention was measured 15 months following licensure. The aim of the current study was thus to assess the contribution of parents’ actual driving behavior, participation in the intervention, and teen drivers’ attitudes towards accompanied driving (measured six months after licensure), to the reported risky driving of the young drivers fifteen months after receiving their driving license. The data consist of a sample of 78 parent-young driver dyads who were originally randomly assigned to one of three intervention groups (receiving different forms of feedback) or a control group (with no feedback). Findings indicate that the feedback and training to parents intervention group, as well as parents’ risky driving events rate, were positively associated with the reported proneness to reckless driving and the reckless driving habits of the young drivers. In addition, lower perception of accompanied driving as enabling a sense of relatedness with parents, and higher negative perceptions of this period, were related to higher reported risky driving among young drivers fifteen months after licensure. The results highlight the importance of parents’ behavior and relationships with their offspring as key concepts in moderating risky driving among young drivers. Practical implications for road safety are discussed.     

Young driving learners’ intention to use a handheld or hands-free mobile phone when driving

This paper presents a survey investigating young driving learners’ intention to use a handheld or hands-free mobile phone when driving. A sample of 164 young driving learners completed a questionnaire based on the theory of planned behavior (TPB), which measured people’s intentions to use mobile phone while driving in handheld condition or hands-free condition, along with their attitudes towards the behavior, subjective norms, perceived behavioral control. The regression analysis models revealed that the TPB was able to explain 43% and 48% variance in hands-free mobile phone use intention and handheld mobile phone use intention, respectively, with perceived behavioral control emerging as the strongest predictor. In addition, TPB components, usage frequency and perceived risk were more dependent on gender than age. These results have several theoretical and practical implications. In particular, interventions should emphasize on the risk of hands-free mobile phone use when driving for young drivers, especially for young male drivers.     

Assessing the effect of long-automated driving operation,repeated take-over requests,and driver’s characteristics on commercial motor vehicle drivers’ driving behavior and reaction time in highly automated vehicles

Automated Commercial Motor Vehicles (CMVs) have the potential to reduce the occurrence of crashes, enhance traffic flow, and reduce the stress of driving to a larger extent. Since fully automated driving (SAE Level 5) is not yet available, automated driving systems cannot perform all driving tasks under all road conditions. Drivers need to regain the vehicle’s control when the system reaches its maximum operational capabilities. This transition from automated to manual is referred to as Take-Over Request (TOR). Evaluating driver’s performance after TORs and assessing effective parameters have gained much attention in recent years. However, few studies have addressed CMV drivers’ driving behavior after TOR and the effect of long-automated driving and repeated TORs. This paper aims to address this gap and gain behavioral insights into CMV drivers’ driving behavior after TOR and assess the effect of the duration of automated operation before TOR, repeated TORs, and driver characteristics (e.g., age, gender, education, and driving history). To accomplish this, we designed a 40-minutes experiment on a driving simulator and assessed the responses of certified CMV drivers to TORs. Drivers’ reaction time and driving behavior indices (e.g., acceleration, velocity, and headway) are compared to continuous manual driving to measure driving behavior differences. Results showed that CMV drivers’ driving behavior changes significantly after the transition to manual regardless of the number of TORs and the duration of automated driving. Findings suggest that 30 min of automated operation intensifies the effect of TOR on driving behaviors. In addition, repeated TOR improves reaction times to TOR and reduces drivers' maximum and minimum speed after TORs. Driver’s age and driving history showed significant effects on reaction time and some driving behavior indices. The findings of this paper provide valuable information to automotive companies and transportation planners on the nature of driver behavior changes due to the carryover effects of manual driving right after automated driving episodes in highly automated vehicles.     

The effects of driving environment complexity and dual tasking on drivers’ mental workload and eye blink behavior

The goal of the present study was to assess the effectiveness of eye blink behavior in measuring drivers’ mental workload. Previous research has shown that when mental workload increases with the primary task difficulty, blink frequency drops. On the opposite, the number of blinks increases when a cognitive secondary task has to be performed concurrently. However, the combined effects of the primary task difficulty and dual-tasking on blink rate have not been investigated. The present study was thus designed to vary systematically both the primary driving task and the cognitive secondary task demand to examine their combined effects on blink rate. The driving task was manipulated by varying the complexity of a simulated driving environment. The cognitive load was manipulated using a concurrent simple reaction time task or a complex calculation task. The results confirmed that eye blink frequency was a sensitive measure to elicit increased mental workload level coming from the driving environment. They also confirmed that blink rate increased with the introduction of a cognitive secondary task while blink duration was not affected. However, eye blink behavior did not provide a clear mental workload signature when driving task demands and dual-task conditions were varied simultaneously. The overall picture goes against the suitability of eye blink behavior to monitor drivers’ states at least when external and internal demands interact.     

Parents’ self-efficacy and the quality of supervised driving practice they provide for their children

Learner drivers must gain supervised driving practice in a wide variety of driving situations to prepare them for independent driving. This study investigated the way that sociodemographic factors, parental self-efficacy and driving self-efficacy of parents are associated with the quality of supervised driving practice they provide to their learner driver children. An online survey was completed by 293 fully licensed parents (female = 86%) of learner (52%) and provisional (intermediate; 48%) drivers from Queensland, Australia. A variable indicating quality of supervised practice was defined based on the understanding that higher frequency and greater variety of driving situations and environments represents higher quality supervised practice. Hierarchical multiple regression was used to analyse parent responses. As predicted, driving self-efficacy was significantly and positively associated with quality of supervised practice. However, no significant association was found between parental self-efficacy and quality of supervised practice. Parent gender and perceived level of involvement were also important predictors of supervised practice quality. The association between previous experience with providing supervised practice and supervised practice quality was unclear. A key implication of this research is that devising methods to improve the driving self-efficacy of parents may contribute to provision of more frequent and varied supervised practice.     

Frequency and impact of hands-free telephoning while driving – Results from naturalistic driving data

The frequency and impact of hands-free telephoning while driving was analyzed based on naturalistic driving data from 106 drivers. The results from naturalistic driving data were compared with the results from experimental approaches. The implication of the overall results and the differences across drivers are discussed. Continuous information on the usage of the hands-free phone equipment was available which made it possible to include the entire database (∼1 000 000 km) in a completely automatized analysis. Results show that drivers talked on a hands-free phone about 11% of driving time. There were large differences across drivers in the frequency and usage of a hands-free phone. While telephoning, an adaptation of driving behavior could be found. Drivers slowed down and increased their distance to the lead vehicle. Furthermore, during telephoning, an overall reduction of potentially critical driving situations was found. Overall, the results indicate that compensation for telephoning was carried out with a long-term change of driving behavior, rather than with a short term adaption to the situation.     

Effect of driving inactivity on driver’s lateral positioning control: A driving simulator study

Overall on-road driving skill is a cumulated acquisition of driving skills learned during training period and furthered tempered with post-licensing driving exposure on the roads. Training serves to develop a person’s basic driving skills to operate safely on the roads at first, while subsequent on-road driving hones the driving skills further. Inactivity from on-road driving can result in deterioration of driving skills. Particularly for the case of inactivity immediately following licensure, which is not uncommon in Singapore, the learned skills can degrade rapidly. This research aims to examine the effect of driving inactivity on the learned driving skill, i.e. lateral positioning control, specifically for young-inexperienced drivers. A series of experiments were conducted on a driving simulator for different subject groups involving active driver, novice driver (freshly-licensed driver), inactive driver (never ever drive upon licensure), and no licence subjects. The participants drove through a stretch of expressway under free-flow conditions, and lane positioning control was monitored. It is found that without on-road driving exposure, driving skills like maintenance of lane positioning control in terms of lane wandering and lane encroachment may deteriorate after some periods of inactivity, i.e. 3 months. The deterioration varies at different rate, with faster deterioration for more complex tasks. The skills level can regress close to un-trained level for complex driving tasks. The findings also suggest that on-road driving exposure is needed to not only retain but also to improve the lane positioning control skills.     

Investigation of drivers’ thresholds of a subjectively accepted driving performance with a focus on automated driving

Lately, the development and implementation of automated driving moved to the center of interest in the automotive industry. In this context, one of the central issues – the configuration of adequate trajectories – is mainly tackled using a technical approach. However, it appears that a technically ideal driving performance does not necessarily coincide with the drivers’ subjective preferences. This study strives to determine thresholds of a subjectively accepted driving performance regarding lateral vehicle control. A second objective is to analyze the influence of selected personal and situational factors on these thresholds. An empirical online survey with 161 participants rating video sequences of driving performances was conducted. The video sequences differed not only with regard to the lateral offset of the ego-vehicle but also concerning the weather (sun/rain) and traffic conditions (existence/driving behavior of oncoming traffic). Additionally, the participants’ driving experience and sensation seeking were considered in the data evaluation. To analyze the data, binary logistic regression analyses were calculated. They revealed that the subjective evaluation of driving performances varies primarily depending on the lateral offset of both the ego-vehicle and the oncoming traffic. The results indicate that regarding the lateral offset certain thresholds of subjectively accepted driving performances do exist. Regarding the development of automated driving systems, two issues need to be considered in order to ultimately guarantee user acceptance. First, the subjective thresholds need to be integrated into the systems’ trajectory planning. Second, the oncoming traffic’s driving behavior has to be considered.