Driver perception hypothesis: Driving simulator study

According the driver perception hypothesis, horizontal curves appear sharper or flatter when overlapping with crest or sag vertical curves, respectively. Confirmations of this hypothesis are provided by studies carried out using non-interactive techniques that do not allow the analysis of the driver’s reactions to the visual perception of the road.This study was aimed to add to the body of knowledge concerning driver’s speed behavior on combined curves, as well as to test the perception hypothesis based on the speed data collected during tests in the interactive CRISS driving simulator.Speeds on the tangent-curve transition of crest and sag combinations were compared to those on the tangent-curve transition of horizontal curves with the same radii but on a flat grade (reference curves).For the crest combinations the results of the statistical analyses were fully consistent with the perception hypothesis. On the sag combinations, on the contrary, the driver’s speed behavior did not differ in any statistically significant way from that on the reference curves. Therefore this finding did not support the perception hypothesis on the sag combinations. The effects of the combined curves on the driver’s speed behavior did not change in function of the level of the radius. Some implications of these findings have been highlighted.     

Externalizing behavior,the UPPS-P Impulsive Behavior scale and Reward and Punishment Sensitivity

The UPPS-P Impulsive Behavior scale is a promising measure of impulsivity facets involved in the etiology of Externalizing behaviors (e.g., substance abuse, antisocial behavior, and aggression). The purpose of this study was to determine whether measures of motivational systems, specifically Reward and Punishment Sensitivity, accounted for variance in Externalizing behaviors beyond the UPPS-P scales. Undergraduates (N = 282; 50% men) completed online self-reports of alcohol and drug use, antisocial behavior, and aggression, as well as the UPPS-P and measures of Reward and Punishment Sensitivity. Principal components analysis was used to create summary Externalizing scores related to Disinhibition and Aggression. Lack of Premeditation, low Perseverance and Sensation Seeking had significant partial relationships with Disinhibition, but Reward Sensitivity accounted for additional variance. Both Reward Sensitivity and (Low) Punishment Sensitivity were related to Aggression, beyond variance explained by UPPS-P Negative Urgency and (lack of) Perseverance. Impulsivity facets appear to have differential relationships with measures of Externalizing and, although the UPPS-P accounts for a significant portion of individual differences, it does not fully account for variance associated with Reward and Punishment Sensitivity.     

Driver social desirability scale: A Turkish adaptation and examination in the driving context

Self-report data collection methods are widely used techniques to gather information in studies related to road safety. One of the most considerable limitations of self-reports is social desirability bias. One way to overcome the possible detrimental effects of socially desirable responding is to control it by using social desirability scales. With respect to that, the present study aims to adapt the Driver Social Desirability Scale into Turkish, examine its construct validity, and investigate the relationship between social desirability and driving-related measures. A total of 351 drivers between the ages of 19 and 59 completed a questionnaire including a demographic information form, the Driver Behavior Questionnaire (DBQ), the Driver Skill Inventory (DSI), the Two-Dimensional Social Desirability Scale (SDS), and the Driver Social Desirability Scale (DSDS). Factor analysis supported the two-factor structure of the DSDS in the Turkish sample. Social desirability correlated positively with age and driving experience. Female drivers reported higher levels of driver impression management, while male drivers scored higher on self-deception. Driver impression management was associated negatively with violations and perceptual-motor skills and positively with safety skills. Lastly, driver self-deception was positively related to violations, positive driver behaviors, perceptual-motor skills, and safety skills. The study shows that the Turkish version of the DSDS is a reliable and structurally valid instrument with incremental validity compared to the general social desirability measure in predicting driving-related outcomes.     

Effects of driving anger on driver behavior – Results from naturalistic driving data

There is a positive relationship between driving anger and near-crash or crash risk. However, it remains unclear if anger in fact contributes to traffic accidents and whether this happens due to cognitive overload or aggressive driving behaviors. This study investigated how anger affects driving behavior based on naturalistic driving data from the second Strategic Highway Research Program (SHRP 2). Ten-minute trip segments were analyzed in which drivers exhibited anger with regard to driving errors, violations, and aggressive expressions. This data was compared to a matched baseline consisting of the same drivers not exhibiting anger. Results showed that anger resulted in more frequent aggressive driving behaviors but did not increase driving error frequency. Anger consequently creates danger due to deliberate behaviors rather than because of cognitive overload. In congruence with this finding, only anger triggered by threats, provocations, and frustrations increased the frequency of deliberate infringements. In contrast, anger due to having conflicts with someone on the phone or with a passenger was not linked to any type of aberrant driving behavior. Finally, severe displays of anger were accompanied by more violations as compared to slight or marked anger.     

Process Analyses of Impulsive Behavior in Binge-Eating Disorder During the Randomized Controlled IMPULS Trial

Impulsivity represents a risk factor for patients with binge-eating disorder, and we therefore investigated the treatment process of impulsive behaviors including binge-eating episodes in the randomized controlled IMPULS trial. Using 8 weekly online questionnaires throughout the assessment period, we compared 41 patients participating in the IMPULS program, which emphasized impulsive eating behavior (IG), with 39 control patients who received no intervention (CG). We assessed the frequency of binge eating, other impulsive behaviors, situations in which such behaviors could be inhibited, and the execution of alternative behaviors. Results indicate a stronger binge-eating reduction in the IG compared to the CG at the fifth, seventh, and eighth treatment weeks. Overall, both groups reduced other impulsive behaviors. They did not differ in the amount of inhibited impulsive behaviors and showed similar alternative behaviors, “distraction” most frequently used. IG patients evaluated the IMPULS program as very helpful. The stronger reduction of binge eating in the IG and positive evaluation of the treatment indicate a specific treatment effect regarding impulsive eating behavior. The reduction of other impulsive behaviors across both groups, and the initial reduction of binge eating within the CG, could be explained by an increased degree of self-observation.     

Driver glance behavior towards displayed images on in-vehicle information systems under real driving conditions

Intelligent vehicle technologies like driver assistance systems and in-vehicle information systems, enhance convenience of the driving experience for drivers and passengers. At the same time, these systems may increase driver distraction and workload. Guidelines developed for this purpose include principles, methods, and assessments which are widely agreed upon, with some being singled out for a particular recommendation or requirement. Especially the display of graphical or photographic images are generally assumed to distract the driver from safely operating the vehicle and should be blocked during driving under all circumstances (so called per se lock outs). This study investigates the effect of displaying graphical and photographical images during driving on driveŕs glance behavior during real-world driving. Findings presented in this paper provide empirical evidence for the unobtrusiveness of these stimuli: Participants didn’t exhibit longer glance durations towards in-vehicle information systems, nor a deterioration of driver distraction parameters such as total eyes off road time and long glance proportion when being compared to driving without displaying any photographic images.     

Assessment of proneness to distraction: English adaptation and validation of the Attention-Related Driving Errors Scale (ARDES) and cross-cultural equivalence

Prior research developed the Attention-Related Driving Errors Scale (ARDES), a 19-item questionnaire aimed at evaluating the drivers’ predisposition to attentional error, and also provided validity evidence of ARDES measures across two countries: Argentina and Spain. In the current work we adapt the Spanish version of the ARDES to the English language and the culture, traffic regulations and driving habits of the UK, and then provide new evidence of the cross-cultural equivalence of the scale. First, an improved forward and backward translation design was used to translate the Spanish ARDES into English. A committee-approach review process was also performed during the translation phase to guarantee that the English ARDES was the most appropriate to reflect the language, culture, traffic regulations and driving habits of the UK. Second, the adapted questionnaire was tested on 301 British drivers to inspect its psychometric properties and study the relationships between the ARDES-UK and different socio-demographic variables. In agreement with the previous literature, the results of the factor analysis confirmed a single factor and accounting for 33.84% of the variance. Cronbach’s alpha was equal to .89. The observed pattern of relationships of the scores and the different socio-demographic variables was consistent with previous evidence and support the validity of the adapted questionnaire. For example, the ARDES-UK scores were significantly different between drivers reporting and not reporting traffic accidents with material damage. To conclude with, the translation design and the resulting psychometric suggest the validity of ARDES-UK measures for evaluating the British drivers’ predisposition to attentional error. In addition, the evidence in the current work supports the hypothesis of the cross-cultural stability of the scale across Spain and the UK.     

冲动性消费行为内在机制研究述评 ———提升调节点在冲动性消费行为中所起作用

有关冲动性消费行为研究的文献众多,但难以从内在联系上进行统一。最近,利用提升调节点对冲动性消费行为内在机制的揭示是该领域的一个突破,从而有望把一些相关文献统一起来。作者介绍了冲动性消费行为内在过程;综述了用于冲动性消费行为内在机制研究的相关理论;从内在机制这个角度对有关冲动性消费行为文献进行评述。文章的最后提出了冲动性消费行为内在机制的进一步研究方向：利用调节点等相关理论,特别是调节适应理论对冲动性消费行为内在机制做进一步探讨     

Evaluation of a dynamic blocking concept to mitigate driver distraction: Three simulator studies

In recent years, the number and complexity of in-vehicle infotainment systems has been steadily increasing. While these systems certainly improve the driving experience, they also increase the risk for driver distraction. International standards and guidelines provide methods of measuring this distraction along with test criteria that help automakers decide whether an interface task is too distracting to be used while driving. Any specific function failing this test should therefore be locked out for use by the driver. This study implemented and tested a dynamic approach to this blocking by algorithmically reacting to driver inputs and the pace of the interaction in order to prevent drivers from having prolonged or too intense sequences of in-vehicle interactions not directly related to driving. Three simulated driving experiments in Germany and the United States were conducted to evaluate this dynamic function blocking concept and also cater for differences in the status quo of either no blocking or static blocking. The experiments consisted of a car following scenario with various secondary interface tasks and always included a baseline condition where no blocking occurred as well as an implementation of the dynamic function blocking. While Experiments 1 and 3 were aimed at collecting and analyzing gaze and driving data from more than 20 participants, Experiment 2 focused on the user experience evaluation of different visual feedback implementations from 13 participants. The user experience as rated by these participants increased throughout the course of all three studies and helped further improve both the concept and feedback design. In the experiments the total glance time towards the road was significantly higher in the dynamic function blocking condition compared to the baseline, already accounting for the increase in total task time inherent to the dynamic condition. Participants developed two strategies of interacting with the dynamic function blocking. They either operated at their normal baseline speed and incurred task blockings or operated slower to avoid the blockings. In the latter strategy, participants chunked their interactions into smaller steps with the present data suggesting that they used the pauses in between chunks to look back onto the road ahead. Theoretical and practical implications of this first evaluation of a dynamic function blocking concept are discussed.     

Influence of pedestrian-to-vehicle technology on drivers’ response and safety benefits considering pre-crash conditions

Pedestrian-to-vehicle (P2V) technology may offer a promising approach to reducing pedestrian crashes. However, its influences on both driver response and safety benefits have been little studied in previous research, particularly in regard to the variation of influences between different pre-crash scenarios. To investigate these influences, this study designed three pre-crash scenarios based on pedestrian crash contributing factors identified from crash reports, and collected 44 drivers’ driving simulator experiments’ data. The results clarified how using P2V technology to warn drivers of an impending collision improves safety by causing a series of changes for both brake operation and braking profile. These series of changes were further demonstrated to vary between scenarios. The study showed that P2V technology may be particularly useful in scenarios in which a pedestrian’s crossing intention is unclear; specifically, in this type of scenario, the P2V warning had changed the braking process from a panic brake of “slow reaction-hard brake” to a comfortable brake of “quick reaction-gentle brake.” In addition, the P2V warning may be less effective in “low-risk” level scenarios where a driver is confident that he/she can handle the situation through a more conservative evasive action and don’t need to react strongly to a warning. Moreover, depending on the pre-crash scenario, the P2V warning may be mostly beneficial for drivers who had a crash/citation in the past five years and working-aged drivers.     

Further evidence of the heterogeneous nature of impulsivity

‘Impulsivity’ refers to a range of behaviours including preference for immediate reward (temporal-impulsivity) and the tendency to make premature decisions (reflection-impulsivity) and responses (motor-impulsivity). The current study aimed to examine how different behavioural and self-report measurements of impulsivity can be categorised into distinct subtypes.Exploratory factor analysis using full information maximum likelihood was conducted on 10 behavioural and 1 self-report measure of impulsivity.Four factors of impulsivity were indicated, with Factor 1 having a high loading of the Stop Signal Task, which measures motor-impulsivity, factor 2 representing reflection-impulsivity with loadings of the Information Sampling Task and Matching Familiar Figures Task, factor 3 representing the Immediate Memory Task, and finally factor 4 which represents the Delay Discounting Questionnaire and The Monetary Choice Questionnaire, measurements of temporal-impulsivity.These findings indicated that impulsivity is not a unitary construct, and instead represents a series of independent subtypes. There was evidence of a distinct reflection-impulsivity factor, providing the first factor analysis support for this subtype. There was also support for additional factors of motor- and temporal-impulsivity. The present findings indicated that a number of currently accepted tasks cannot be considered as indexing motor- and temporal-impulsivity suggesting that additional characterisations of impulsivity may be required.     

Validation of the German version of the Driver Skill Inventory (DSI) and the Driver Social Desirability Scales (DSDS)

The psychometric properties of the new German versions of the Driver Skill Inventory (DSI) and the Driver Social Desirability Scales (DSDS) were examined. The DSI is a self-report measure assessing perceptual-motor skills and the safety motive as two important aspects of driving behavior. Self-report measures, however, are susceptible to socially desirable responding (SDR) which is why both general and specific driving-related SDR scales have been developed: Based on the Balanced Inventory of Desirable Responding (BIDR), the DSDS taps Driver Impression Management and Driver Self-Deception as two important aspects of SDR. In two validation studies with less experienced (N = 130) and experienced drivers (N = 1199), both inventories showed the expected two-factor structure and satisfactory internal consistency. In Study 1, self-ratings were compared with and confirmed by peer-ratings. In both studies, we accumulated evidence of convergent and discriminant validity for the German version of the DSI by correlating it with demographic, driving-specific, and personality measures, including the Big Five, Type A behavior, and sensation seeking. The DSI seemed to be only marginally contaminated by SDR.     

Effects of directional auditory and visual warnings at intersections on reaction times and speed reduction times

Intersection collision warning systems (ICWSs) have an important impact on driving safety because making the potential collision at intersection predictable, allow reducing the probability and severity of accidents. Among the several types of alarms to alert the driver of an imminent collision, those most used concerning the auditory and the visual stimulus. However, it is unclear whether is more effective an audio or a visual warning. In addition, no study compared the effects on drivers’ behavior induced by an acoustic and a visual directional warning. The main objective of the present study was to assess, in response to a potential conflict event at the intersections, the effects of directional auditory and visual warnings on driving performance.A driving simulator experiment was carried out to collect drivers’ behavior in response to a vehicle that failed to stop at the intersection. The parameters reaction time and speed reduction time were used for the evaluation of the effects on driving performance. These duration variables were modeled following the survival analysis, by the use of the accelerated failure time duration model with a Weibull distribution.Results showed that when the directional warning system (auditory or visual) was present, the drivers were able to detect earlier the violator vehicle. This effect led to a more comfortable braking maneuver and, thus, less possibilities of an unexpected maneuver for the following vehicle, avoiding the car – following collisions. The effectiveness of ICWSs was more evident for the directional auditory speech message; for this condition, in fact, the lower reaction time and the longer speed reduction time were obtained.The outcomes of the present study provide useful suggestions about the most effective collision warning systems that the automotive industry should develop and equip on vehicles.     

Investigating driving instructors: The mediating roles of driving skills in the relationship between organizational safety strategies and driver behaviours

The aim of the present study is to investigate the mediating roles of driving skills in relationship between organizational safety strategies and driver behaviours among driving instructors. Driving skills consist of perceptual-motor skills and safety skills. Driver behaviours are investigated under four factors: violations, errors, lapses, and positive driver behaviours. Participants were 132 driving instructors (108 male and 24 female). In order to measure organizational safety strategies, Organizational Safety Strategies Scale (OSSS) was developed for driving schools. Results of the principal component analyses yielded one-factor solution for OSSS. In order to test the indirect effects of organizational safety strategies on driver behaviours through driving skills, multiple mediation analyses were conducted by entering age and annual mileage as the control variables. As organizational safety strategies were stronger, driving instructors had higher levels of perceptual-motor skills, which resulted in higher violations. On the other hand, as organizational safety strategies were stronger, driving instructors had higher levels of safety skills, which resulted in less violations and lapses. It can be inferred that; organizational stronger safety strategies might have negative influences on road safety through higher perceptual-motor skills; whereas there can be positive influences on road safety through higher safety skills. In addition, both skills are related to organizational safety strategies. Hence, driving schools should consider the asymmetric relationship between perceptual-motor skills and safety skills while improving their safety strategies to decrease violations and lapses. Organizations might also develop interventions to balance the stated skills to increase road safety.     

Driver's avoidance characteristics to hazardous situations: A driving simulator study

When analyzing the causes of an accident, it is critical to determine whether the driver could have prevented the accident. In previous studies on the reaction times of drivers, the definition and values of reaction times vary, so applying reaction time is difficult. In such analysis, the driver’s reaction time from perception is required to determine whether the driver could have prevented the accident, but past studies are difficult to utilize in accident analysis as reaction time measurements were taken after the occurrence of hazardous situations. In this study, 93 subjects from age groups ranging from 20 s to 40 s participated in an experiment inside a full-scale driving simulator, to determine reaction time values that can be practically applied to accident analysis. A total of 4 hazardous accident situations were reproduced, including driving over the centerline, pedestrian jaywalking, a vehicle cutting in, and intersection traffic signal violation. The Time-To-Collision (TTC) was 2.5 s and the driving speed was set to the common city road speed limits of 60 and 80 km/h. An eye tracker was used to determine the driver’s Saccade Latency (SL) during hazardous situations. Brake Reaction Time from Perception (BRT_P), Steer Reaction Time from Perception (SRT_P), and Driver Reaction Time from Perception (DRT_P) were derived, and the measurements were statistically analyzed to investigate differences by age group, gender, speed, and type of hazardous situation. Most participants were found to avoid collisions by braking first rather than steering for the presented hazardous situations, except for the cutting in situation. Also, to determine a reaction time that would cover most drivers, the 85th percentile of DRT_P was calculated. The 85th percentile of DRT_P was in the range of 0.550 – 0.800 s. Specifically for each hazardous situation, it was 0.650 s for driving over the centerline, 0.800 s for the pedestrian jaywalking, 0.660 s for cutting in, and 0.550 s for the intersection traffic signal violation. For all 4 hazardous situations combined, the 85th percentile of DRT_P was 0.646 s. The findings can be utilized to determine the driver’s likelihood of avoiding accidents when faced with similar hazardous situations.     

Driving around bends with or without shoulders: The influence of bend direction

Paved shoulders have long been used to create “forgiving” roads where drivers can maintain control of their vehicles even when as they drift out of the lane. While the safety benefits of shoulders have been well documented, their effects on driver behavior around curves have scarcely been examined. The purpose of this paper is to fill this gap by assessing whether the addition of shoulders affects driver behavior differently as a function of bend direction. Driver behavior in a driving simulator was analyzed on left and right curves of two-lane rural roads in the presence and absence of 0.75-m and 1.25-m shoulders. The results demonstrated significant changes in drivers’ lateral control when shoulders were provided. In the absence of oncoming traffic, the shoulders caused participants to deviate more toward the inner lane edge at curve entry, at the apex and at the innermost position on right bends but not left ones. In the presence of oncoming traffic, this also occurred at the apex and the innermost position, leading participants to spend more time off the lane on right curves. Participants did not slow down in either traffic condition to compensate for steering farther inside, thereby increasing the risk of lane departure on right curves equipped with shoulders. These findings highlight the direction-specific influence of shoulders on a driver’s steering control when driving around bends. They provide arguments supporting the idea that drivers view paved shoulders as a new field of safe travel on right curves. Recommendations are made to encourage drivers to keep their vehicle within the lane on right bends and to prevent potential interference with cyclists when a shoulder is present.     

Valid representation of a highly dynamic collision avoidance scenario in a driving simulator

In Germany the second-most frequent accidents in road traffic are rear-end collisions. For this reason rear-end collisions are quite important for accident research and the development of driving safety systems. To examine the functionality and to design the human–machine-interface of new driving safety systems, especially in the early development phase, subject tests are necessary. Because of the great hazard potential of such safety critical scenarios for the test persons, they are often conducted in a driving simulator (DS). Accordingly, validity is an important qualification to ensure that the findings collected in a simulated test environment can be directly transferred to the real world.This paper regards the question of driving behavior validity of DS in critical situations. There are hardly any validation studies which analyze the driving behavior in a specific collision avoidance situation.The validation study described in this paper aims to evaluate the behavioral validity of a fixed-base simulator in a collision avoidance situation. For this reason a field study from 2007 was replicated in a fixed-base simulator environment.The main questions of this validation study were if the driver can notice an active hazard braking system and if the driving behavior in a static simulator can be valid in such a critical situation.The key finding of the study states that there is no driving behavior validity in a static driving simulator for the tested dynamic scenario. The missing vestibular feedback causes a different behavior of the participants in field and simulator. The resulting absence of comparability leads to non-valid performance indicators. But these indicators are key parameters for analyzing the function and acceptance of active braking systems. So the question arises, which motion performance does a motion base have to provide in order to achieve valid acceleration simulation of such a highly dynamic collision avoidance scenario. The DS’s performance is measured in workspace, velocity and acceleration.     

Effects of forward collision warning technology in different pre-crash scenarios

The forward collision warning (FCW) system is expected to reduce rear-end crashes; however, its effects on driving behavior and safety have not been thoroughly investigated, specifically the effect variations between different pre-crash scenarios. To identify these variations, this study conducted a driving simulator experiment and compared the FCW’s effects between three pre-crash scenarios: the freeway scenario, the arterial scenario and the intersection dilemma zone scenario. Thirty-nine participants were involved in the experiment. The results showed that the adaptation of driver behavior in impending rear-end collision events resulted from both the FCW and the scenario. The intersection dilemma zone scenario has indications of slowing down, which encouraged drivers to take a more aggressive response strategy under the FCW; the arterial scenario might be regarded as an “easy-to-handle” situation in which a significant portion of drivers adopted moderate level of response strategy under the FCW; both the intersection dilemma zone scenario and freeway scenario have burdened driving tasks, and this might deteriorate a driver’s ability to adapt to the FCW. In addition, different types of drivers experienced varied benefits from the FCW in each scenario. The FCW would be particularly recommended for non-experienced drivers in the freeway scenario and for female drivers in the arterial scenario; moreover, in the scenario of the intersection dilemma zone, the FCW would be particularly recommended for drivers who have a crash/citation before. The results also support specific FCW designs which are able to highlight the collision risk. This study demonstrated that it would be better to indicate the effects of the FCW under the restriction of specific scenario features and develop the FCW based on that.     

Justification of Violence and Grandiosity Schemas as Predictors of Antisocial Behavior in Adolescents

This study assessed the role of grandiosity and justification of violence cognitive schemas as predictors of adolescents’ antisocial behavior. The 974 Spanish adolescents (457 girls and 517 boys, aged between 14 and 18 years) were assessed at the beginning of the school year and at follow-up 6 months later. They completed measures of aggressive behavior and delinquent behavior, justification of violence and grandiosity cognitive schemas, and impulsivity. The results showed that grandiosity and justification of violence schemas predicted both aggressive and delinquent behavior 6 months later and that the association between grandiosity and aggressive behavior was moderated by impulsivity in boys. In general, the influence of the cognitive schemas in antisocial behavior was very similar for boys and girls. However, boys showed higher delinquent behavior rates than did girls and the tests of mediation revealed that this difference was partially accounted for by boys’ higher scores in grandiosity and justification of violence.