1. Study suggests drivers find it harder to ignore a ringing phone than to ignore the risk

    September 19, 2017 by Ashley

    From the Queensland University of Technology press release:

    Drivers find it difficult to ignore a ringing phone but they do ignore the dangers, with a new QUT study revealing almost 50 per cent believe locating and answering a ringing phone is not as risky as talking and texting.

    The research undertaken by QUT’s Centre for Accident Research & Road Safety — Queensland (CARRS-Q) and published in the PLOS ONE journal has found locating a ringing phone, checking who is calling, and rejecting or answering the call, is the most frequent mobile phone task undertaken by drivers.

    Lead researcher Oscar Oviedo-Trespalacios said drivers did not believe that locating and answering a ringing phone was as risky as talking, texting or browsing.

    “The study of 484 Queensland drivers found 45 per cent admit to locating and answering a ringing phone, compared to 28 per cent who reported speaking on a handheld device.

    “Also concerning is that more drivers reported looking at a screen for more than 2 seconds or locating and answering a ringing phone, than they did talking on a handheld phone, texting or browsing.”

    Mr Oviedo-Trespalacios said when considering the risk of these different mobile phone tasks, most drivers underestimated the distracting dangers of passive phone use.

    Finding and reaching for a ringing phone is perceived by drivers as having a mid-range crash risk, however research has showed that this task is one of the most risky activities a driver can engage in,” he said.

    “This is because drivers are likely to adapt their driving behaviour when talking, texting and browsing, by reducing their speed, increasing their distance from the vehicle in front and scanning their environment more frequently.

    “On the other hand, a ringing mobile phone can occur at any time without giving time for the driver to adapt their behaviour and therefore increases the likelihood of a crash. “This mismatch in perception of risk is a major concern revealed by the study.”

    Mr Oviedo-Trespalacios said using a mobile phone while driving had been shown to increase crash risk four-fold.

    “Novice drivers are particularly at risk as they are more likely to drive while using a mobile phone.”

    Mr Oviedo-Trespalacios said other findings in the study included:

    • Despite the research, 12 per cent drivers still don’t believe talking on a handheld phone is dangerous
    • Drivers actively avoid police detection, with about 70 per cent admitting to being on the lookout for police when using their phone
    • Drivers keep their phones low and cover them to evade police detection
    • On a typical day, drivers are more likely to look at their mobile phone for more than 2 seconds, than they are to text or browse

  2. Study suggests mind wandering is common during driving

    September 16, 2017 by Ashley

    From the Frontiers press release:

    Researchers in the United States have investigated mind wandering in volunteers during a driving simulation. When prompted at random during the simulation, the volunteers reported mind wandering 70% of the time. Using electrophysiological measurements, the researchers could identify specific changes in brain patterns when the volunteers were mind wandering.

    Are you always attentive when driving? How about on the monotonous commute home after a long day’s work? It can be difficult to keep our attention sharp while driving, especially on routes that we drive daily, or when we are tired after work. However, driver inattention is a major factor in road traffic crashes and fatalities. The most obvious sources of driver distraction are external, such as phones or other mobile devices, and scientists have extensively studied the role of these distractions in road accidents.

    However, many traffic accidents occur without any obvious external distractions. Mind wandering is an understudied form of distraction, where drivers start daydreaming and shift their attention from driving to internal thoughts. To stay safe, drivers need to remain aware of other road users and respond rapidly to unexpected events, and mind wandering might reduce their ability to do so. Because drivers may not be explicitly aware that their mind is wandering, it can be difficult to quantify it.

    In a recent study, published in Frontiers in Human Neuroscience, American scientists investigated how frequent mind wandering is during a driving simulation, and whether they could find tell-tale changes in brain patterns for a wandering mind.

    The researchers asked a group of volunteers to use a driving simulator, while hooked up to an electrophysiological monitoring system, to measure electrical activity in their brains. For five days in a row, the volunteers completed two 20-minute driving simulations along a monotonous stretch of straight highway at a constant speed, to mimic a commute to and from work. Between the two “commutes,” they completed a written test to simulate the mentally draining effect of a day’s work.

    Throughout the experiment, the volunteers heard a buzzer at random intervals, and every time the buzzer sounded they used a tablet computer to indicate if their mind had been wandering right before they heard the buzzer, and if so, if they had been explicitly aware of their mind wandering or not.

    “We found that during simulated driving, people’s minds wander a lot — some upwards of 70% of the time,” says Carryl Baldwin, of George Mason University, who was involved in the study. Participants’ minds were more likely to wander on the second drive of the simulation (the drive home after work), and on average, they were aware of their mind wandering only 65% of the time.

    The scientists could also directly detect mind wandering from the volunteers’ brain activity. “We were able to detect periods of mind wandering through distinctive electrophysiological brain patterns, some of which indicated that the drivers were likely less receptive to external stimuli,” says Baldwin.

    So, what does this mean? Is mind wandering dangerous, and if so, can we stop doing it? “Mind wandering may be an essential part of human existence and unavoidable. It may be a way to restore the mind after a long day at the office,” says Baldwin. “What we are not sure about yet, is how dangerous it is during driving. We need additional research to figure this out,” she explains. “In terms of improving safety in the future, one option could be autonomous transport systems, like self-driving cars, that allow people’s minds to wander when it is safe to do so, but re-engage when they need to pay attention.”


  3. Signs of distracted driving: Pounding heart, sweaty nose

    August 30, 2017 by Ashley

    From the University of Houston press release:

    Distracted driving — texting or absent-mindedness — claims thousands of lives a year. Researchers from the University of Houston and the Texas A&M Transportation Institute have produced an extensive dataset examining how drivers react to different types of distractions, part of an effort to devise strategies for making driving safer.

    In a paper published Aug. 15 in the journal Scientific Data, the researchers make the dataset publicly available for the first time and describe how they collected the information.

    The study was conducted with 68 volunteers, all of whom had a valid driver’s license and normal or corrected-to-normal vision, on a driving simulator. Drivers were tracked with both thermal and visual cameras, along with palm sensors, sensors to measure heart rate and breathing rate, and an eye tracking system.

    Ioannis Pavlidis, Eckhard Pfeiffer Professor and director of the Computational Physiology Lab at UH, said the study is the first to tackle three types of distracting elementssensorimotor, such as texting; cognitive, such as absorbing thoughts; and emotional distractions.

    Texting, the researchers found, led to far more dangerous driving, while a “sixth sense” appeared to protect those suffering emotional upset or absent-mindedness. Texting interfered with that sixth sense, letting drivers drift out of their traffic lanes. The researchers reported this result in the journal Scientific Reports last year, using a subset of the data they collected.

    Additional investigation showed that “eye tracking and breathing rate proved useful metrics for measuring the impact of texting while driving,” Pavlidis said. “But that wasn’t helpful in cases of emotional or cognitive distractions.” However, he said the researchers found heart rate signals captured via wearable sensors and perinasal perspiration captured via miniature thermal imagers were able to track all forms of distraction — a result that is reported in the current Scientific Data paper.

    That and other findings provide the groundwork for future safety systems, said Robert Wunderlich, director of the Center for Transportation Safety at the Texas A&M Transportation Institute. Given the widespread use of smart watches capable of measuring heart rate, he said this result opens the way for universal sensing of all forms of distraction at the consequential source, that is, the driver’s sympathetic system.

    The potential market for interventions is huge. According to the National Highway Traffic Safety Administration, 3,477 people were killed and 391,000 were injured in motor vehicle crashes involving distracted drivers in 2015. Texas Gov. Greg Abbott signed a law banning texting while driving earlier this summer, leaving just three states that have not banned the practice.

    The experiment worked like this: Volunteers drove the same segment of highway four times in a high-fidelity driving simulator — with no distraction and with cognitive, emotional and physical distraction. They were monitored via standoff and wearable sensors, which recorded perspiration, heart rate, breathing rate, gaze and facial expressions to capture the drivers’ state as they were overloaded by multitasking.

    At the same time, the simulator’s computer recorded driving performance variables including speed, acceleration, braking force, steering angle and lane position.

    In addition to Pavlidis, authors on the paper include Panagiotis Tsiamyrtzis of Athens University of Economics and Business, who spearheaded the data analysis and validation; Salah Taamneh and Ashik Khatri of UH; Malcolm Dcosta of Elizabeth City State University; Pradeep Buddharaju of University of Houston-Clear Lake; Michael Manser and Robert Wunderlich of the Texas A&M Transportation Institute; and Thomas Ferris of Texas A&M University.

    Along with the publication of the paper in Scientific Data, the researchers released the full dataset in the Open Science Framework (OSF) databank.

    This experiment represents an emerging form of multimodal design, where an abundance of highly quantitative variables are measured continuously, providing a 360-degree view of the studied conditions. Pavlidis noted that these designs are now possible because of technological advances in wearable and imaging sensors, as well as the emergence of robust computational algorithms.

    The deluge of data such multimodal experiments produce requires sophisticated curation and complete openness, he said, not only for purposes of reproducibility but also as a means to investigate the dataset’s full potential.


  4. Which bar patrons underestimate their inebriation the most?

    July 27, 2017 by Ashley

    From the Research Society on Alcoholism press release:

    Prior research suggests that college students, males, and people drinking alcohol at restaurants, bars, and nightclubs are at particularly high risk for driving after drinking. Breath-testing devices are not usually found at these drinking establishments, so patrons generally assess their own intoxication levels using internal (feelings of intoxication) and external (number of drinks consumed) cues. This study examined bar patrons’ self-estimates of their breath alcohol concentrations (BrACs) in natural drinking environments.

    Researchers recruited 510 study participants, on 14 nights between 10 p.m. and 3 a.m., as they exited two bars located close to large universities: one in Florida (n=301) and the other in Texas (n=209). Research assistants conducted a 10-15 minute interview with each of the exiting patrons and measured their BrAC with hand-held testing devices.

    Bar patrons with the highest-measured BrACs underestimated their levels the most. Adjusting for their measured BrAC, individuals who felt more intoxicated or who reported consuming more drinks thought that their BrACs were higher. However, more than 20 percent of participants with a BrAC of at least 0.08% (the legal driving limit) thought that their BrAC was below this level. Individuals younger than 26 and those who reported feeling less drunk were more likely to make this error. Study authors called for more research to assess the association between self-estimated BrACs and driving behavior in different contexts, and to investigate how altering drinking environments could improve individuals’ ability to self-estimate their BrACs and avoid driving after drinking.


  5. Study suggests people walking to work or an errand more likely to stroll into dangerous areas

    June 3, 2017 by Ashley

    From the Drexel University press release:

    People taking leisurely strolls tend to choose safer walking routes than those heading to work or on an errand, a new study found.

    Led by D. Alex Quistberg, Ph.D., an assistant research professor in the Dornsife School of Public Health at Drexel University, the study used GPS, accelerometers and travel logs from a 2008-2009 survey in King County, Washington — which includes Seattle — to measure the path and purpose of 537 pedestrians. That data was then compared to maps on the probability of pedestrian collision risk, and the study was published in the American Journal of Epidemiology.

    Quistberg and his team found that pedestrians on recreational walks were 8 percent less likely to be in areas where car collision risks were higher than those on utilitarian walks (walking somewhere with a purpose).

    “There’s likely a mix of things happening here,” Quistberg said. “On recreational walks, people likely want a more relaxing path than someone on a utilitarian walk.”

    The study also found that people who took longer walks, both in distance and time, were less likely to stray into dangerous areas (where car-collision risk is high). That, too, was likely tied to recreational walks vs. walks with a purpose. The study also took demographic data into account. This yielded the finding that people who lived in single-family homes, owned homes and/or owned a car all were less likely to walk in more dangerous areas.

    People who participated in the survey who had children were slightly less likely — around 2 percent — to walk in areas with high collision risk.

    “This could be due to people with children living in single-family homes, which are usually in neighborhoods that have a low risk of pedestrians collisions because of low traffic and slow speeds,” Quistberg explained. “It is also possible that people with children at home are walking more cautiously, perhaps with their children.”

    Recently, Dornsife School of Public Health Dean Ana Diez Roux, M.D., Ph.D., signed on to a letter supported by former president Jimmy Carter that appealed for protection of the walking paths of children, especially those headed to school. And although results from Quistberg’s study analyze adult pedestrians in Washington state, he believes they reveal information that could serve to improve walkability universally.

    “Improving road safety for pedestrians will support interest in walking for recreation as well as those who integrate a healthy walk into their commute,” Quistberg said.


  6. Study suggests perceptual judgment, motor skills not fully developed until age 14

    April 24, 2017 by Ashley

    From the University of Iowa press release:

    For adults, crossing the street by foot seems easy. You take stock of the traffic and calculate the time it will take to get from one side to the other without being hit.

    Yet it’s anything but simple for a child.

    New research from the University of Iowa shows children under certain ages lack the perceptual judgment and motor skills to cross a busy road consistently without putting themselves in danger. The researchers placed children from 6 to 14 years old in a realistic simulated environment and asked them to cross one lane of a busy road multiple times.

    The results: Children up to their early teenage years had difficulty consistently crossing the street safely, with accident rates as high as 8 percent with 6-year-olds. Only by age 14 did children navigate street crossing without incident, while 12-year-olds mostly compensated for inferior road-crossing motor skills by choosing bigger gaps in traffic.

    “Some people think younger children may be able to perform like adults when crossing the street,” says Jodie Plumert, professor in the UI’s Department of Psychological and Brain Sciences. “Our study shows that’s not necessarily the case on busy roads where traffic doesn’t stop.”

    For parents, that means taking extra precautions. Be aware that your child may struggle with identifying gaps in traffic large enough to cross safely. Young children also may not have developed the fine motor skills to step into the street the moment a car has passed, like adults have mastered. And, your child may allow eagerness to outweigh reason when judging the best time to cross a busy street.

    “They get the pressure of not wanting to wait combined with these less-mature abilities,” says Plumert, corresponding author on the study, which appears in the Journal of Experimental Psychology: Human Perception and Performance, published by the American Psychological Association. “And that’s what makes it a risky situation.”

    The National Center for Statistics and Analysis reported 8,000 injuries and 207 fatalities involving motor vehicles and pedestrians age 14 and younger in 2014.

    Plumert and her team wanted to understand the reasons behind the accident rates. For the study, they recruited children who were 6, 8, 10, 12, and 14 years old, as well as a control group of adults. Each participant faced a string of approaching virtual vehicles travelling 25 mph (considered a benchmark speed for a residential neighborhood) and then crossed a single lane of traffic (about nine feet wide). The time between vehicles ranged from two to five seconds. Each participant negotiated a road crossing 20 times, for about 2,000 total trips involving the age groups.

    The crossings took place in an immersive, 3-D interactive space at the Hank Virtual Environments Lab on the UI campus. The simulated environment is “very compelling,” says Elizabeth O’Neal, a graduate student in psychological and brain sciences and the study’s first author. “We often had kids reach out and try to touch the cars.”

    The researchers found 6-year-olds were struck by vehicles 8 percent of the time; 8-year-olds were struck 6 percent; 10-year-olds were struck 5 percent; and 12-year-olds were struck 2 percent. Those age 14 and older had no accidents.

    Children contend with two main variables when deciding whether it’s safe to cross a street, according to the research. The first involves their perceptual ability, or how they judge the gap between a passing car and an oncoming vehicle, taking into account the oncoming car’s speed and distance from the crossing. Younger children, the study found, had more difficulty making consistently accurate perceptual decisions.

    The second variable was their motor skills: How quickly do children time their step from the curb into the street after a car just passed? Younger children were incapable of timing that first step as precisely as adults, which in effect gave them less time to cross the street before the next car arrived.

    “Most kids choose similar size gaps (between the passing car and oncoming vehicle) as adults,” O’Neal says, “but they’re not able to time their movement into traffic as well as adults can.”

    The researchers found children as young as 6 crossed the street as quickly as adults, eliminating crossing speed as a possible cause for pedestrian-vehicle collisions.

    So what’s a child to do? One recommendation is for parents to teach their children to be patient and to encourage younger ones to choose gaps that are even larger than the gaps adults would choose for themselves, O’Neal says. Also, civic planners can help by identifying places where children are likely to cross streets and make sure those intersections have a pedestrian-crossing aid.

    “If there are places where kids are highly likely to cross the road, because it’s the most efficient route to school, for example, and traffic doesn’t stop there, it would be wise to have crosswalks,” Plumert says.


  7. Study suggests hands-free technology may still affect driver attention

    April 20, 2017 by Ashley

    From the Human Factors and Ergonomics Society press release:

    Drivers commonly perform secondary tasks while behind the wheel to navigate or communicate with others, which has led to a significant increase in the number of injuries and fatalities attributed to distracted driving. Advances in wearable technology, particularly devices such as Google Glass, which feature voice control and head-up display (HUD) functionalities, raise questions about how these devices might impact driver attention when used in vehicles. New human factors/ergonomics research examines how these interface characteristics can have a deleterious effect on safety.

    In their Human Factors article, “Driving While Interacting With Google Glass: Investigating the Combined Effect of Head-Up Display and Hands-Free Input on Driving Safety and Multitask Performance,” authors Kathryn Tippey, Elayaraj Sivaraj, and Thomas Ferris observed the performance of 24 participants in a driving simulator. The participants engaged in four texting-while-driving tasks: baseline (driving only), and driving plus reading and responding to text messages via (a) a smartphone keyboard, (b) a smartphone voice-to text system, and (c) Google Glass’s voice-to-text system using HUD.

    The authors found that driving performance degraded regardless of secondary texting task type, but manual entry led to slower reaction times and significantly more eyes-off-road glances than voice-to-text input using both smartphones and Google Glass. Glass’ HUD function required only a change in eye direction to read and respond to text messages, rather than the more disruptive change in head and body posture associated with smartphones. Participants also reported that Glass was easier to use and interfered less with driving than did the other devices tested.

    Tippey, a postdoctoral research fellow at the Center for Research and Innovation in Systems Safety at the Vanderbilt University Medical Center, says, “Our evidence suggests that adding voice input and using an HUD can make secondary tasks like texting while driving less unsafe. However, regardless of entry or display method, it is not safe to perform these types of secondary task while driving in environments where the workload from driving is already heavy.”


  8. Drivers who slow down while using mobile phones may potentially increase on-road conflicts

    April 17, 2017 by Ashley

    From the Queensland University of Technology press release:

    Drivers who slow down while using mobile phones have the potential to increase on-road conflicts, a new QUT study warns.

    Oscar Oviedo-Trespalacios, from QUT’s Centre for Accident Research & Road Safety — Queensland (CARRS-Q), said distracted drivers reducing their speed might sound favourable in terms of safety, but it could also lead to other types of crash risk.

    Drivers frustrated by following slow moving vehicles whose drivers have reduced speed to keep talking on their phones may perform aggressive overtaking manoeuvres, increasing the crash risk for other road users,” he said.

    The results of the study “Effects of road infrastructure and traffic complexity in speed adaptation behaviour of distracted drivers” have been published in the leading road safety journal Accident Analysis and Prevention.

    Mr Oviedo-Trespalacios said using a mobile phone while driving had been shown to increase crash risk four-fold.

    “Young drivers are particularly at risk as there is a greater prevalence of driving while using a mobile phone in this age group.

    “While it’s illegal to use a handheld mobile phone while driving in Australia research has shown drivers continue to adopt the dangerous practice.”

    In a bid to highlight the dangers but also identify possible solutions, Mr Oviedo-Trespalacios’ research has looked at the way drivers react and respond to mobile phone use behind the wheel.

    “We found that on average distracted drivers travel at about 5km/h slower when following another vehicle and almost 3km/h slower in free-flowing traffic.

    “The negative consequences this has on other road users include increased risk of nose-to-tail crashes as a result of sudden stopping, perception of discourteous or aggressive driver behaviour, as well congestion to the transport system,” he said.

    “I guess the question needs to be asked, do we really want to sacrifice safety, efficiency and courtesy just to have a conversation?”

    Mr Oviedo-Trespalacios said the research also suggested ideas for safe ways to use mobile phones while driving.

    “We need to consider that if we can’t stop drivers using their mobile phones, is there a way to make it safe?

    “For example, changing the design of mobile phones so they are context-aware and only work when it is safe to do so.

    “Other options maybe looking at advances in technology and developing warning systems that alert drivers when they are distracted, or advise drivers of when it is safe to use their phone handsfree.”


  9. Study suggests brain can’t cope with making a left-hand turn and talking on hands-free cell phone

    March 4, 2013 by Ashley

    From the St. Michael’s Hospital press release via EurekAlert!:

    driving frustrationMost serious traffic accidents occur when drivers are making a left-hand turn at a busy intersection.

    When those drivers are also talking on a hands-free cell phone, “that could be the most dangerous thing they ever do on the road,” said Dr. Tom Schweizer, a researcher at St. Michael’s Hospital.

    Researchers led by Dr. Schweizer tested healthy young drivers operating a novel driving simulator equipped with a steering wheel, brake pedal and accelerator inside a high-powered functional MRI. All previous studies on distracted driving have used just a joy-stick or trackball or else patients passively watching scenarios on a screen.

    Immersing a driving simulator with a fully functional steering wheel and pedals in an MRI at Sunnybrook Health Sciences Centre allowed researchers to map in real time which parts of the brain were activated or deactivated as the simulator took them through increasingly difficult driving maneuvers.

    The researchers were able to show for the first time that making a left-hand turn requires a huge amount of brain activation and involves far more areas of the brain than driving on a straight road or other maneuvers.

    When the drivers were also involved in a conversation, the part of the brain that controls vision significantly reduced its activity as the part that controls monitoring a conversation and attention was activated.

    The research was published today online in the open access journal Frontiers in Human Neuroscience.

    Visually, a left-hand turn is quite demanding,” Dr. Schweizer said. “You have to look at oncoming traffic, pedestrians and lights, and coordinate all that. Add talking on a cell phone, and your visual area shuts down significantly, which obviously is key to performing the maneuver.”

    The simulation had the drivers making six left turns with oncoming traffic, which required them to decide when to turn safely. It then distracted them, by making them answer a series of true-false audio questions, such as “Does a triangle have four sides?” The MRIs showed that blood moved from the visual cortex, which controls sight, to the prefrontal cortex, which controls decision-making.

    “Brain activity shifted dramatically from the posterior, visual and spatial areas [of the brain] to the prefrontal cortex,” said Dr. Schweizer, a neuroscientist and director of the Neuroscience Research Program at the hospital’s Li Ka Shing Knowledge Institute.

    “This study provides real-time neuroimaging evidence supporting previous behavioural observations suggesting that multitasking while driving may compromise vision and alertness. ‘Hands free’ not does mean ‘brains free.'”

    Dr. Schweizer said his study needed to be replicated in larger groups and with various age groups and with people with known brain impairments such as Alzheimer’s disease.


  10. Study examines causes of road rage

    January 15, 2013 by Sue

    From the Centre for Addiction and Mental Health press release via EurekAlert!:

    driving frustrationCutting in and weaving, speeding, and hostile displays are among the top online complaints posted by drivers, according to a new study by the Centre for Addiction and Mental Health (CAMH) recently published in an online issue of Accident Analysis and Prevention.

    Driver aggression is a major safety concern and researchers estimate this behaviour is a factor in nearly half of all motor vehicle collisions. Identifying the underlying causes and strategies for preventing driver aggression continues to be a priority.

    CAMH researcher Dr. Christine Wickens reviewed thousands of entries posted on RoadRagers.com, a website that invites drivers to submit complaints about unsafe and improper driving.

    Following a previous study evaluating complaints submitted to the Ontario Provincial Police, Dr. Wickens turned her attention towards the crop of new websites that ask drivers to describe the unsafe driving practices they’ve observed.

    “These websites can tell us more about what people are doing out there in the real world,” she explained.

    Dr. Wickens, a post-doctoral fellow with CAMH’s Social and Epidemiological Research Department, and her colleagues evaluated more than 5,000 entries posted on RoadRagers.com between 1999 and 2007. The team sorted the complaints — which consisted mostly of reports on driving in Canada and the U.S. — into various categories, including: speeding/racing, erratic/improper braking and blocking.

    The most common complaints involved cutting in and weaving (54 per cent of all complaints), speeding (29 per cent) and hostile displays (25 per cent).

    The research team also discussed how slighted drivers might feel compelled to retaliate or ‘teach other drivers a lesson.’ In some extreme cases, one reckless action can escalate into a hostile situation between multiple drivers.

    The next step in the research will be to examine how slighted drivers perceive the offensive actions of another motorist: Is the other driver in a rush, negligent, or deliberately aggressive? How do these different interpretations affect how we respond?

    With this in mind, Dr. Wickens advises drivers to work hard at keeping cool behind the wheel.

    Remind yourself to take a deep breath, stay calm, and do whatever it takes to bring your anger down,” she said.

    Dr. Wickens suggested that educating drivers during their training on the most common complaints might help them realize the impact of their actions and avoid these types of behaviours. The training could also teach drivers to be aware of their own responses associated with behaviours they are likely to encounter on the road.