The tendency of drivers to pass other vehicles

The purpose of this study was to assess the speed differential threshold—if there is one—at which drivers decide to pass a lead vehicle. Drivers in a simulator encountered vehicles in front that were programmed to travel at speeds that were similar, slightly below, or even slightly above the drivers’ own speed. The study involved a total of 152 such passing opportunities. In almost all of the encounters with slower vehicles (traveling at speeds slower than 3 km/h of the driver) they passed them, and in two thirds of the encounters when the lead vehicles were moving at their speed they passed them too. Most surprising was that in 50% of the encounters drivers passed the lead vehicle when it was traveling faster than their average speed. In these situations drivers actually increased their own speed substantially to accomplish the passing maneuver, despite the fact that not passing the lead vehicle would not have caused any delays. The tendency to pass appears to be related to the drivers’ own speed variability: the more variable the driver’s speed the more likely he or she was to pass the vehicle ahead even when its speed was greater than their average speed. The results are interpreted in terms of (a) driver aggression, and (b) association of car following with added effort, attention overload, or risk. The latter explanation implies that the tendency to pass vehicles may be reduced with the introduction of in-vehicle technologies such as adaptive cruise control.     

Exploring the beliefs underpinning drivers’ intentions to comply with speed limits

Using the theory of planned behaviour (TPB; [Ajzen, I. (1985). From intentions to actions: A theory of planned behavior. In J. Kuhl, J. Beckmann (Eds.), Action control: From cognition to behavior (pp. 11–39). Berlin: Springer-Verlag.]) as a theoretical framework, the present study was designed to: (a) identify the beliefs underpinning drivers’ intentions to comply with speed limits, and (b) test the expectancy-value theory held to underpin those beliefs. A sample of drivers (N = 598) completed questionnaires designed to measure TPB variables with respect to compliance with speed limits. The results of hierarchical multiple regression analyses provided support for the expectancy-value theory held to underpin each behavioural beliefs (outcome beliefs X outcome evaluations), normative beliefs (referent beliefs X motivation to comply), and control beliefs (control frequency beliefs X control power beliefs). Belief targets for road safety countermeasures that aim persuade drivers to comply with speed limits were also identified by selecting those beliefs that were the statistically significant predictors of direct TPB measures (attitudes, subjective norm, perceived control) and intention. Theoretical and practical implications of the results are discussed.     

Posttraumatic Stress Disorder and executive dysfunction among children and adolescents: A Latent Profile Analysis

Background/ObjectiveThe current study aimed to examine the relationship between Posttraumatic Stress Disorder (PTSD) symptoms and executive dysfunction in children and adolescents after psychological trauma.MethodParticipants were 13,438 of children and adolescents aged 6 to 18 years exposed to the 2008 Wenchuan earthquake. PTSD and dysexecutive symptoms were assessed using the UCLA PTSD Reaction Index for Children and the Self-Report Dysexecutive Questionnaire. Latent Profile Analysis (LPA) was conducted using Mplus version 7.4. Subgroup differences in trauma exposure and quality of life were calculated using ANCOVA.ResultsA 4-class parallel model was found to best describe latent PTSD symptom profiles and executive dysfunction. Individuals in higher symptom groups showed more trauma exposure and lower quality of life.ConclusionsThis LPA study shed light on the relationship between PTSD and executive dysfunction symptoms in children and adolescents. The correlation between PTSD and executive dysfunction was maintained after individual differences were taken into consideration. Our findings provide a new view on how PTSD relates to executive dysfunction and several suggestions for treating child and adolescent PTSD patients.     

How to define the accident risk level of car drivers by combining objective and subjective measures of driving style

Perceived risk can be defined as the expectation of being involved in a traffic accident. Traffic risk perception is often subjectively evaluated being risk perception as highly individual, and depending on experiences with accidents. For this reason, a subjective measure of risk level can be useful. On the other hand, accident risk level can be measured also through objective measures, consisting in kinematic parameters defining the driving style. At this aim, it is very important to analyse instantaneous and geo-referenced travelling kinematic parameters of the vehicle recorded by real tests on the road.The aim of this paper is to identify the accident risk level of each driver based on a methodology combining both subjective and objective parameters. Specifically, by using the proposed methodology the risk can be measured immediately by using only the kinematic parameters adopted when driving; we defined three levels of risk of being involved in a road accident (low, medium, and high risk). We retain that our research can give a contribution in terms of improvement of road safety, because the distorted perception of risk level is one of the main causes of road accidents. Very often, drivers are not aware of the risk taking; therefore, it is necessary to raise the awareness of drivers to have safer driving. The proposed method can be useful for informing the driver on the level of risk he/she assumes, so that he/she can take the necessary precautions next time that will cover that stretch of road.     

Field operational test of a seatbelt reminder system: Effects on driver behaviour and acceptance

The long-term effects on driver behaviour and acceptance of a seatbelt reminder system were examined in an on-road study. The system was capable of detecting seatbelt use in all seating positions and produced a two-stage visual and auditory warning if occupants were unrestrained. The effects of this system were evaluated alone and in combination with two other intelligent transport systems: intelligent speed adaptation and a following distance warning system. Twenty-three fleet car drivers drove an instrumented vehicle (SafeCar) for at least 16,500 km as part of their everyday driving. The results revealed that driver and passenger interaction with the seatbelt reminder system led to large and significant decreases in the percentage of trips where occupants were unbelted, in the percentage of total driving time spent unbelted, and in the time taken to fasten a seatbelt in response to system warnings. The seatbelt reminder system was rated by drivers as being useful, effective and socially acceptable, and led to a decrease in drivers’ subjective workload. These results were found even though the baseline pre-exposure seatbelt wearing compliance rates among participants were high.     

Errors in children's subtraction

Many of the errors that occur in children' subtraction are due to the use of incorrect strategies rather than to the incorrect recall of number facts. A production system is presented for performing written subtraction which is consistent with an earlier analysis of the nature of such a cognitive skill. Most of the incorrect strategies used by schoolchildren can be accounted for in a principled way by simple changes in the production system, such as the omission of individual rules or the inclusion of rules appropriate to other arithmetical tasks. The production system model is evaluated against a corpus of over 1500 subtraction problems done by 10-year olds and is shown to account for about two-thirds of the (nonnumber fact) errors. It also provides an alternative, simpler interpretation of the subtraction errors analysed by Brown and Burton (1978). Some implications for teaching are discussed.     

Predictors of perceived road collision/incident risk among horse users: A survey study from Norway

Although horse users in traffic are a vulnerable road user group, traffic safety problems among them are scantly examined by previous research. The main aim of the present study was to examine the role of some demographic variables, traffic safety attitudes, and level of knowledge about rules and regulations applying to horse use in traffic for predicting perceived road collision/incident risk in a sample of horse users in Norway. An online survey was conducted to collect data from a total of 1733 horse users including horse riders and drivers of horse-drawn sulky, wagon or sled. The respondents accessed the survey via a link put to the website of the Norwegian Horse Centre, which is in contact with many different horse user environments in Norway. The majority of the respondents were female and between the ages of 18–30. A multiple regression analysis was conducted to examine the predictors of the perceived collision/incident risk involving other motor vehicles. Results showed that traffic safety attitudes among horse users were the strongest predictor of the perceived collision/incident risk. In particular, horse users reported a negative attitude towards the other road users (e.g. drivers) indicating that they perceive the other road users’ actions and approaches as the biggest source of risk in road traffic. The level of knowledge about the rules and regulations applying to horse use, especially in walking and cycling lane, was relatively low among the respondents. However, knowledge about rules and regulations did not appear as a strong predictor of the perceived collision/incident risk. Results indicate the need to increase road users, especially drivers’, awareness about the problems and needs of horse users in traffic.     

Factors underpinning unsafe driving: A systematic literature review of car drivers

ObjectivesThe purpose was to provide a systematic review of the literature related to the personality and well-being of social, domestic, pleasure and commuting (SDP&C) car drivers.MethodsThe following databases were searched: PsychINFO (PsychNET), Scopus (Elsevier), Web of Science (Social Sciences Index; WoS), ORCA (Online research at Cardiff University), Science Direct (Elsevier), Taylor and Francis Online, and PubMed. Grey literature was sourced using the Transport Research International Database (TRID) as well as conference proceedings of the Human Factors and Ergonomics Society and Driver Assessment. In parallel, an internet search of Google Scholar was undertaken. Two researchers reviewed papers suitable for inclusion. Eligible papers were those published in the English language, during the last decade; the latter to allow for a more contemporary appraisal of the literature. The search yielded thirty peer reviewed articles and ten reports relevant to the personality and well-being of SDP&C road users.ResultsThe findings show that anxiety, stress and depression were predictive of unfavourable driving outcomes (e.g. risk-taking, aggression, poor driving behaviour.) Further, driving discourtesy by others was found to not only induce stress reactions in drivers, but also led to riskier driving practice, such as deliberately engaging in intimidating driving behaviour. Negative personality traits were related with negative driving behaviours, whilst higher levels of well-being and life satisfaction appear to safeguard drivers against deliberate driving violations. There was a dearth of literature focusing on UK drivers, as well as research examining the impact of driving itself on the well-being of the driver.ConclusionsFurther longitudinal, multivariate research is required to examine all well-being/personality predictors, whilst controlling for established predictors (such as fatigue) such that the factors underpinning unsafe driving behaviour (in isolation and in combination) may be revealed.     

A diary study of distracted driving behaviours

The introduction and uptake of technology within road vehicles has readily advanced the capabilities and the functions that the driver of a road vehicle has available to them. While this has benefited the drivers’ productivity and entertainment behind the wheel, it has also heightened the possibility for distraction. Research into driver distraction to date has identified how technologies inside the vehicle may be used ineffectively and can compromise the safety of the road transport system. Yet, the factors that drivers state impact on their decision to engage with distracting technologies are less well known. This paper presents the first diary study into driver distraction. The study asked drivers to record all technological distractions that they engaged with across a 4-week period, as well as interactions that they ignored or choose not to engage with. The diary entries include the technologies drivers interacted with and the conditions surrounding this, as well as external factors that drivers cited to influence their decision to interact. Primarily, factors relating to the task itself were found to be of most importance to the drivers’ decision to engage. Differences were also found in how drivers stated they compensated for any engagement with distracting tasks. This has important consequences for the design and integration of technological devices into the vehicle. The novel application of the method offers insights into the naturalistic conditions surrounding drivers’ involvement with distracting technologies. The method is also reviewed on its applicability to the study of driver distraction.