Individual differences in drivers’ cognitive processing of road safety messages

Using Gray and McNaughton's (2000) revised reinforcement sensitivity theory (r-RST), we examined the influence of personality on processing of words presented in gain-framed and loss-framed anti-speeding messages and how the processing biases associated with personality influenced message acceptance. The r-RST predicts that the nervous system regulates personality and that behaviour is dependent upon the activation of the behavioural activation system (BAS), activated by reward cues and the fight-flight-freeze system (FFFS), activated by punishment cues. According to r-RST, individuals differ in the sensitivities of their BAS and FFFS (i.e., weak to strong), which in turn leads to stable patterns of behaviour in the presence of rewards and punishments, respectively. It was hypothesised that individual differences in personality (i.e., strength of the BAS and the FFFS) would influence the degree of both message processing (as measured by reaction time to previously viewed message words) and message acceptance (measured three ways by perceived message effectiveness, behavioural intentions, and attitudes). Specifically, it was anticipated that, individuals with a stronger BAS would process the words presented in the gain-frame messages faster than those with a weaker BAS and individuals with a stronger FFFS would process the words presented in the loss-frame messages faster than those with a weaker FFFS. Further, it was expected that greater processing (faster reaction times) would be associated with greater acceptance for that message. Driver licence holding students (N = 108) were recruited to view one of four anti-speeding messages (i.e., social gain-frame, social loss-frame, physical gain-frame, and physical loss-frame). A computerised lexical decision task assessed participants’ subsequent reaction times to message words, as an indicator of the extent of processing of the previously viewed message. Self-report measures assessed personality and the three message acceptance measures. As predicted, the degree of initial processing of the content of the social gain-framed message mediated the relationship between the reward sensitive trait and message effectiveness. Initial processing of the physical loss-framed message partially mediated the relationship between the punishment sensitive trait and both message effectiveness and behavioural intention ratings. These results show that reward sensitivity and punishment sensitivity traits influence cognitive processing of gain-framed and loss-framed message content, respectively, and subsequently, message effectiveness and behavioural intention ratings. Specifically, a range of road safety messages (i.e., gain-frame and loss-frame messages) could be designed which align with the processing biases associated with personality and which would target those individuals who are sensitive to rewards and those who are sensitive to punishments.     

Risky and aggressive driving in young adults: Personality matters

Young, novice drivers constitute a disproportionate percentage of fatalities and injuries in road traffic accidents around the world. This study, attempts to identify motivational factors behind risky driving behavior, and examines the role of personality, especially sensation seeking, impulsivity and sensitivity to punishment/reward in predicting negative driving outcomes (accident involvement and traffic offences) among young drivers. Gender and driver's age are additional factors examined in relation to driving outcomes and personality. Adopting the contextual mediated model of traffic accident involvement (Sümer, 2003), the study is based on the theory that personality, age and gender represent distal factors that predict accident involvement indirectly through their relationship with stable tendencies towards aberrant driving behavior. Results from correlations and Structural Equation Modeling using AMOS 6 indicated that direct personality effects on driving outcomes were few, whereas personality had significant correlations with aberrant driving behavior, showing that personality is a distal but important predictor of negative driving outcomes. These high risk traits appear to be at a peak among young male drivers. Thus, personality is important in understanding aggressive and risky driving by young adults and needs to be taken into consideration in designing targeted accident prevention policies.     

A further exploration of sensation seeking propensity,reward sensitivity,depression, anxiety,and the risky behaviour of young novice drivers in a structural equation model

Young novice drivers constitute a major public health concern due to the number of crashes in which they are involved, and the resultant injuries and fatalities. Previous research suggests psychological traits (reward sensitivity, sensation seeking propensity), and psychological states (anxiety, depression) influence their risky behaviour. The relationships between gender, anxiety, depression, reward sensitivity, sensation seeking propensity and risky driving are explored. Participants (390 intermediate drivers, 17–25 years) completed two online surveys at a six month interval. Surveys comprised sociodemographics, Brief Sensation Seeking Scale, Kessler's Psychological Distress Scale, an abridged Sensitivity to Reward Questionnaire, and risky driving behaviour was measured by the Behaviour of Young Novice Drivers Scale. Structural equation modelling revealed anxiety, reward sensitivity and sensation seeking propensity predicted risky driving. Gender was a moderator, with only reward sensitivity predicting risky driving for males. Future interventions which consider the role of rewards, sensation seeking, and mental health may contribute to improved road safety for younger and older road users alike.     

Age dependence of attitudes and knowledge in cyclists

A number of factors related to bicycle accidents were studied, namely, knowledge of priority rules, attitude and self-reported behavior regarding traffic rules, and general opinions about the safety of the traffic behavior of cyclists and drivers. In order to get an indication of the influence of these factors at different stages of the life span, subjects ranging from 9 to 83 years of age were represented in the study. The relationship between age and the various measures was found to be U-shaped in most cases. The older cyclists and the 9 to 11 year olds, the two groups that are most at risk, were deficient regarding knowledge while showing the most positive attitudes. Implications with respect to possible counter measures are discussed.     

An approximate sensitivity analysis of results from complex computer models in the presence of epistemic and aleatory uncertainties

This paper focuses on sensitivity analysis of results from computer models in which both epistemic and aleatory uncertainties are present. Sensitivity is defined in the sense of “uncertainty importance” in order to identify and to rank the principal sources of epistemic uncertainty. A natural and consistent way to arrive at sensitivity results in such cases would be a two-dimensional or double-loop nested Monte Carlo sampling strategy in which the epistemic parameters are sampled in the outer loop and the aleatory variables are sampled in the nested inner loop. However, the computational effort of this procedure may be prohibitive for complex and time-demanding codes. This paper therefore suggests an approximate method for sensitivity analysis based on particular one-dimensional or single-loop sampling procedures, which require substantially less computational effort. From the results of such sampling one can obtain approximate estimates of several standard uncertainty importance measures for the aleatory probability distributions and related probabilistic quantities of the model outcomes of interest. The reliability of the approximate sensitivity results depends on the effect of all epistemic uncertainties on the total joint epistemic and aleatory uncertainty of the outcome. The magnitude of this effect can be expressed quantitatively and estimated from the same single-loop samples. The higher it is the more accurate the approximate sensitivity results will be. A case study, which shows that the results from the proposed approximate method are comparable to those obtained with the full two-dimensional approach, is provided.     

Monotony of road environment and driver fatigue: a simulator study

Studies have shown that drowsiness and hypovigilance frequently occur during highway driving and that they may have serious implications in terms of accident causation. This paper focuses on the task induced factors that are involved in the development of these phenomena. A driving simulator study was conducted in order to evaluate the impact of the monotony of roadside visual stimulation using a steering wheel movement (SWM) analysis procedure. Fifty-six male subjects each drove during two different 40-min periods. In one case, roadside visual stimuli were essentially repetitive and monotonous, while in the other one, the environment contained disparate visual elements aiming to disrupt monotony without changing road geometry. Subject's driving performance was compared across these conditions in order to determine whether disruptions of monotony can have a positive effect and help alleviate driver fatigue. Results reveal an early time-on-task effect on driving performance for both driving periods and more frequent large SWM when driving in the more monotonous road environment, which implies greater fatigue and vigilance decrements. Implications in terms of environmental countermeasures for driver fatigue are discussed.     

Race,Hispanic origin,and socioeconomic status in relation to motor vehicle occupant death rates and risk factors among adults

Black and Hispanic adults travel less in motor vehicles than whites but may be at greater risk when they do travel. Passenger vehicle occupant deaths per 10 million trips among persons ages 25-64 were computed by race, Hispanic origin, gender, and socioeconomic status (SES) using 1995 data from the Fatality Analysis Reporting System (FARS) and Nationwide Personal Transportation Survey. Educational level was used as the indicator of SES. Blacks, particularly black men, were at increased risk of dying relative to whites when traveling in motor vehicles (rate ratio (RR) for black men=1.48; 95% confidence interval (CI)=1.42-1.54). Hispanic men, but not Hispanic women, also had elevated occupant death rates, but their risk was less than that of black men (RR=1.26; 95% CI=1.20-1.31). SES was the strongest determinant of occupant deaths per unit of travel; RRs among those who had not completed high school were 3.52 (95% CI=3.39-3.65) for men and 2.79 (95% CI=2.69-2.91) for women, respectively. Whites without high school degrees had the highest death rates per 10 million trips. After adjustment for SES, the elevated risk of occupant fatalities persisted among black men and women, but not among Hispanic men. Seat belt use and alcohol-impaired driving were examined among fatally injured passenger vehicle drivers. Among those with no education beyond high school, higher percentages were reported as having high blood alcohol concentrations (BACs) or having not used belts. Reported belt use rates were lower among black men and women, even after controlling for SES, whereas Hispanic men and women had belt use rates similar to those of whites. High BACs were more common among Hispanic men, which appeared largely to be an effect of SES because most Hispanic men killed in crashes had not completed high school, the education level with the highest percentage that drove while impaired by alcohol. More effective public health efforts are needed to reduce occupant deaths among persons of lower SES, blacks, and Hispanics, including measures to increase use of seat belts and reduce alcohol-impaired driving.     

Can anyone reward safe driving?

It is widely held that reward is better than punishment for shaping behaviour, yet it seems virtually absent from the learning situation for safe driving. This paper discusses why this is so, and why most attempts to introduce reward have been futile. Inadvertently, however, reward appears to have been introduced into the driving that is done by those who have been suspended or disqualified, in that they are rewarded for driving safely and inconspicuously. The good driving records shown by disqualified drivers after licence restoration suggests that a powerful learning mechanism is at work. Possible means are discussed by which this effect might be harnessed and be made to occur more generally in those who are learning to drive.     

A flow metamodel for delivery agents over a spatial area

This article studies fuzzy rules that were used to model autonomous entities and discusses the development of a metamodel to describe the traffic flow of autonomous agents over a spatial area. The agents deliver goods (and themselves) to prespecified locations on the given spatial area. The metamodel is defined as a set of equations, obtained through regression analysis, that are functions of several variables that affect the agent system. The performance measures are effective speed and collision probability. The fuzziest rule set consistently gave the best results in terms of collision avoidance for this study. The improved collision avoidance is gained at the cost of a lower effective speed. A “traffic control” policy may be desirable when congestion reaches a limit. The flow metamodel equations describe the emergent behavior of the system, or system-level behavior resulting from interactions at the level of the parts of the system. The equations can be used to determine whether congestion will be a problem before designing a system containing entities that navigate among themselves. The flow metamodel curves suggest combinations of system parameters that will alleviate congestion. The results have implications for several practical applications.     

An application of Stafford and Warr's reconceptualisation of deterrence to a group of recidivist drink drivers

Recent revisions of deterrence theory have highlighted the powerful effects of personal and vicarious punishment avoidance on criminal activity. The present paper reports on an application of Stafford and Warr's [Stafford, M.C., Warr, M., 1993. A reconceptualization of general and specific deterrence. J. Res. Crime Delinq. 30 (2), 123-135] reconceptualisation of deterrence theory to a group of recidivist drink drivers to explain their self-reported offending behaviours. The analysis indicated that punishment avoidance exerted the greatest influence on self-reported offending behaviours, although perceptions of arrest certainty and severity also appear associated with drink driving offences. In contrast, vicarious exposure to others who have been punished or avoided punishment was not associated with further drink driving behaviours. The results suggest that recidivist drink drivers are not heavily influenced by vicarious experiences, and that past behaviour is an efficient predictor of future behaviour. The findings have direct implications for the reconceptualisation and application of deterrence models to elucidate offending behaviours.     

Venturesomeness and extraversion as correlates of juvenile drivers' traffic violations

Ninety-eight juvenile traffic offenders, 81 men and 17 women, were examined regarding the personality traits of extraversion, neuroticism, psychoticism, impulsiveness and venturesomeness and compared with a control group of 149 applicants for driving licences, 82 male and 67 female. The participants of the study were administered German translations of the Eysenck personality questionnaire (EPQ-R) and the impulsiveness/venturesomeness/empathy questionnaire (IVE). Traffic offenders had significantly higher scores on the venturesomeness dimension as compared to the control group, and male offenders scored significantly higher on extraversion than did male controls. Hypotheses regarding a relationship between traffic offences and psychoticism and impulsiveness were not confirmed, however. It is concluded that traffic violations in juveniles should primarily be viewed within the scope of normal behaviour and do not necessarily imply serious personality disorder.     

Effect of exposure to aggressive stimuli on aggressive driving behavior at pedestrian crossings at unmarked roadways

BackgroundAggressive driving, influenced by the proneness of driving aggression, angry state and provoking situation, is adversely affecting traffic safety especially in developing countries where pedestrians frequently cross an unmarked crosswalk. Exposure to aggressive stimuli causes driving anger and aggressive driving behaviors, but the exposure effect on higher and lower aggression drivers and their cumulative changes under successive exposures need more investigation.ObjectivesAn experiment was conducted to examine (1) driving behaviors of individuals with higher and lower aggressive driving traits when approaching pedestrian crossings at unmarked roadways with and without aggressive provocation; and (2) cumulative changes of driving performance under repeated provocations.MethodWe conducted a driving simulator study with 50 participants. Trait of aggressive driving served as a between-subjects variable: participants with an Aggressive Driving Scale (ADS) total score of 30 or more (for men) or 23 or more (for women) were regarded as higher aggressive drivers; lower aggressive drivers were those individuals whose ADS total scores were 21 or less (for men) or 13 or less (for women). Exposure to aggressive stimuli (provoked vs. non-provoked condition) served as a within-subjects variable. Several aspects of the participants’ minimum driving speed, lateral distance from a simulated pedestrian, lateral deviation, and subjective measures were collected.ResultsWe found that drivers with higher aggressive driving traits were more likely to feel irritated and fail to give way for pedestrians and drove closer to pedestrians when exposed to sustained honking and improper passing compared to the non-provoked condition. This trait × state interaction only occurred when pedestrians crossed the street from the right roadway edge line. In addition, we observed an accumulation effect of exposure to aggressive stimuli on driver's aggressive behaviors at pedestrian crossings.ConclusionsEnvironmental design, law enforcement, and educational campaign may have practical value for reducing pedestrian and driver conflicts at unmarked roadways.     

Drivers' reactions to sudden braking by lead car under varying workload conditions; towards a driver support system

At urban intersections drivers handle multiple tasks simultaneously, making urban driving a complex task. An advanced driver assistance system may support drivers in this specific driving task, but the design details of such a system need to be determined before they can be fully deployed. A driving simulator experiment was conducted to determine the relationship between different subtasks of driving at urban intersections. Participants completed four drives, each comprising 20 comparable intersections with different traffic situations and encountered one unexpected braking event during the experiment. The effects of varying levels of event urgency on the relationship between different driving subtasks were studied. Furthermore, the influence of workload on this relationship was determined by giving half of the subjects an additional cognitive task. After the lead car braked unexpectedly, participants reduced speed and increased headway depending on the urgency of the braking event. Depending on the workload, participants returned to the normal speed and headway again after a number of intersections. Participants experiencing a high-workload drove more smoothly, except for those who had experienced the most urgent unexpected event. High workload additionally affected the length of the adjustments to the unexpected event.     

Less is more: the influence of traffic count on drinking and driving behaviour

Drinking and driving road checks are often organized with either a clear prevention or repression objective in mind. The objective of a prevention strategy is to make as many people as possible believe that police officers are enforcing drinking and driving laws and that drinking drivers will most likely be caught. As such, targeting high traffic count road sites with high-visibility road checks is a priority because it serves to increase awareness of the enforcement activity. An alternative to this prevention approach is the “repression” approach that involves targeting times and places where the highest number of drinking drivers are to be expected. Rather than attempting to affect the subjective chance of getting caught, this approach seeks to increase the objective likelihood of getting caught; the aim is to apprehend as many drinking drivers as possible. Regardless of the chosen strategy, there is a need to understand how traffic count influences drinking and driving behaviour as traffic count may play a role in a police officer's choice of sites for a road check. The objective of this paper is to shed some light on this relationship between drinking and driving behaviour and traffic count. In this paper, data from a roadside survey, carried out in British Columbia in 2003, are used. A two-level logistic regression analysis was carried out with data from 2627 drivers coming from 48 different road sites to replicate a model that was previously obtained with comparable data from a Belgian roadside survey, also carried out in 2003. The present study successfully replicated the findings of the Belgian model, substantiating that the probability for drivers to be drinking and driving significantly decreases with an increasing level of traffic count. This supports the suggestion that drinking drivers avoid high traffic count road sites. The relevance of these findings with respect to organizing preventive or repressive road checks and possible confounding variables are discussed at the end of this paper.     

Simulation of size-effect behaviour through sensitivity analyses

Sensitivity analysis techniques are applied to the simulation of size effect behaviour. The scale factor is included in the discretised equilibrium equations. A gradient-enhanced damage model is used. The sensitivity of the equilibrium path with respect to the loading factor is then obtained through the direct differentiation method. Particular attention is paid to the proper differentiation of constitutive internal variables. The predictive possibilities of the algorithm are illustrated by means of an example.     

Exploring the effects of attitudinal and perception characteristics on drinking and driving non-compliant behaviour

The objective of this paper is to examine a number of factors (observed and latent) that might have a causal effect on drinking and driving (D&D) behaviour. Face-to-face surveys were conducted among patrons at bars and cafeterias and 305 valid questionnaires were filled. A confirmatory factor analysis was performed so as to identify the latent constructs and a mixed structural equation model was developed. From the analysis it came up that non-compliant behaviour of D&D is limited at older ages, also associated with high levels of income and car availability. Though men are consuming more alcohol, women seem to be more prone in driving under the influence (DUI) of alcohol. Furthermore, it was found that people who strongly support the examined interventions in the study (e.g. better enforcement, more traffic safety campaigns, stricter penalties) are more unlikely to drive after drinking compare to those who have some objections. Finally, it was not found any statistically significant relation between individuals’ level of awareness and D&D behaviour.     

Drink driving and traffic accidents in young people

The relationship between drink driving behaviours and rates of traffic accidents was analysed in a birth cohort of 907 New Zealand young people studied to the age of 21. Drink driving was significantly (P<0.0001) related to active traffic accidents in which the driver’s behaviour contributed to the accident but was not related to passive accidents in which driver behaviours did not contribute to the accident (P>0.15). Those engaging in high rates of drink driving had rates of active traffic accidents that were 2.6 times higher than those who did not drink and drive. Further analysis suggested that much of this association was explained by confounding factors (and notably driver behaviour) that were associated with both drink driving and accident rates. After adjustment for confounding factors, those engaging in high rates of drink driving had rates of active accidents that were 1.5 (P<0.01) times higher than those who did not drink and drive. It is concluded that although the study findings support the view that the regulation of drink driving behaviour amongst young people is likely to contribute to a reduction in traffic accidents, to be fully effective attempts at regulation of drink driving also need to be accompanied by a similar level of investment in regulating other aspects of risky or illegal driving behaviour amongst young people.     

The bold and the fearless among us: Elevated psychopathic traits and levels of anxiety and fear are associated with specific aberrant driving behaviors

In spite of the well-documented connection between personality traits like impulsivity, sensation seeking and fearlessness with aberrant driving behaviors, scarce research exists to examine the association between risky and aggressive driving and psychopathic characteristics, which encompass the above traits. The present investigation examines in two studies the association between specific sub-types of driving misconduct, i.e., unintentional mistakes and deliberate rule violations with psychopathic characteristics, with a focus on the role of levels of fear and anxiety in aberrant driving. Findings support the hypotheses that fearlessness, i.e., the bold, unemotional aspect of psychopathic traits, characterizes drivers who engage in frequent deliberate driving code violations, whereas the more impulsive/antisocial aspect of psychopathy, associated with higher levels of fear and anxiety, is more characteristic of drivers who engage in unintentional mistakes. Fearless features are also associated with higher self-reported driving misconduct and accidents. Study 2 conceptually replicated this finding by showing that mistakes are positively related to high sensitivity to punishment, while violations are negatively related to it. Findings are discussed in light of psychopathy theory and in relation to prevention and intervention.     

Sensitivity analysis for reliable design verification of nuclear turbosets

In this paper, we present an application of sensitivity analysis for design verification of nuclear turbosets. Before the acquisition of a turbogenerator, energy power operators perform independent design assessment in order to assure safe operating conditions of the new machine in its environment. Variables of interest are related to the vibration behaviour of the machine: its eigenfrequencies and dynamic sensitivity to unbalance. In the framework of design verification, epistemic uncertainties are preponderant. This lack of knowledge is due to inexistent or imprecise information about the design as well as to interaction of the rotating machinery with supporting and sub-structures. Sensitivity analysis enables the analyst to rank sources of uncertainty with respect to their importance and, possibly, to screen out insignificant sources of uncertainty. Further studies, if necessary, can then focus on predominant parameters. In particular, the constructor can be asked for detailed information only about the most significant parameters.     

A parameter tree approach to estimating system sensitivities to parameter sets

A post-processing technique for determining relative system sensitivity to groups of parameters and system components is presented. It is assumed that an appropriate parametric model is used to simulate system behavior using Monte Carlo techniques and that a set of realizations of system output(s) is available. The objective of our technique is to analyze the input vectors and the corresponding output vectors (that is, post-process the results) to estimate the relative sensitivity of the output to input parameters (taken singly and as a group) and thereby rank them. This technique is different from the design of experimental techniques in that a partitioning of the parameter space is not required before the simulation. A tree structure (which looks similar to an event tree) is developed to better explain the technique. Each limb of the tree represents a particular combination of parameters or a combination of system components. For convenience and to distinguish it from the event tree, we call it the parameter tree.To construct the parameter tree, the samples of input parameter values are treated as either a “+” or a “−” based on whether or not the sampled parameter value is greater than or less than a specified branching criterion (e.g., mean, median, percentile of the population). The corresponding system outputs are also segregated into similar bins. Partitioning the first parameter into a “+” or a “−” bin creates the first level of the tree containing two branches. At the next level, realizations associated with each first-level branch are further partitioned into two bins using the branching criteria on the second parameter and so on until the tree is fully populated. Relative sensitivities are then inferred from the number of samples associated with each branch of the tree.The parameter tree approach is illustrated by applying it to a number of preliminary simulations of the proposed high-level radioactive waste repository at Yucca Mountain, NV. Using a Total System Performance Assessment Code called TPA, realizations are obtained and analyzed. In the examples presented, groups of five important parameters, one for each level of the tree, are used to identify branches of the tree and construct the bins. In the first example, the five important parameters are selected by more traditional sensitivity analysis techniques. This example shows that relatively few branches of the tree dominate system performance. In another example, the same realizations are used but the most important five-parameter set is determined in a stepwise manner (using the parameter tree technique) and it is found that these five parameters do not match the five of the first example. This important result shows that sensitivities based on individual parameters (i.e. one parameter at a time) may differ from sensitivities estimated based on joint sets of parameters (i.e. two or more parameters at a time).The technique is extended using subsystem outputs to define the branches of the tree. The subsystem outputs used in this example are the total cumulative radionuclide release (TCR) from the engineered barriers, unsaturated zone, and saturated zone over 10,000 yr. The technique is found to be successful in estimating the relative influence of each of these three subsystems on the overall system behavior.