The following text is about the work social psychologists could do to understand and reduce road traffic crashes and by hence help to reduce them.

Most road traffic crashes (RTC) lead to injuries and fatalities, but what mechanism work as they occur? What is going on right before the crash and leads to or trigger it? So far we have understand that human and behavioral factors are the most important factors in predicting road traffic crashes, rather than for instance technical issues. In the following we will elaborate on these factors.

Explaining Driving Behavior

The Influence of Behaviors and Attitudes

What causes our behavior?

The most predictive behavior for crashes is violations which is the deliberate and intentional disregard of traffic rules. There are two different forms of violations:

1. Aggressive violation: this kind of violation is usually triggered by anger about another driver and leads to actions like chasing or thwarting someone

2. Ordinary violations: violations that most people engage in from time to time, like slight speeding for example

If you on the other hand just failed to act correctly without any intention to do so, it is called errors. These can, depending on their severity also lead to road traffic crashes sometimes with harming consequences.

Lapses happen if a driver deviates from the expected behavior, like signaling to turn left instead of right. Usually they occur without severe safety impairments.

In general we have to notice that there are a lot of cultural differences. Something that we would call an aggressive violation might be normal in a different culture.

Theory of Planned Behavior

An influential social psychological theory is the “Theory of Planned Behavior” which argues that there are factors that predict our behavior.

It starts with the intention we have to engage in a specific behavior. This intention has a direct effect on our behavior and is itself influenced by three different factors:

• Attitudes: our evaluation of a specific behavior which can either be positive or negative (e.g. we do not like speeding, because it scares us)

• Subjective norms: what we think is the right or the wrong thing to do (we do not think breaking the law is good therefore we stop at a red traffic light)

• Perceived Behavioural control: to which extent we feel that we have the control about a specific behavior

Attitudes, subjective norms and perceived behavioral control are factors which have an indirect impact on behavior by influencing the intentions to engage in it.

Downsides of the Theory of Planned Behavior are that is disregards any contextual and environmental influences like weather conditions, as well as any individual differences, like personality characteristics.

The Influence of Personality and Individual Differences

Who does it?

Individual personality characteristics and the way drivers think about their own driving capabilities are also important factors contributing to behavior on the road. Sensation seeking for instance is the need for different and new sensations and experiences. People engage in behavior that fulfills this need even if it comes with physical and/or social risks.

Another good predictor of road traffic crashes is aggression. Feeling aggressive while driving usually leads to violations and risky driving patterns. We differentiate between state aggression which refers to the anger we experience in a certain situation and environment, at that specific moment. Most people experience state aggression at some point in their life. Trait aggression on the other hand refers to a more or less stable personality characteristic.

Other factors influencing traffic behavior will be discussed now.

The illusion of control is what makes people think they can handle every situation. Related to this is the self-enhancement bias which involves having unrealistic positive judgments regarding the self. In the context of driving it leads for example to an overestimation of ones driving skills. Especially male and young drivers tend to overestimate their driving abilities while elderly are more cautious about that.

People with a lot of driving experience are also at a higher risk since they usually estimate their driving skills unrealistically high, which might put them into dangerous situations.

Another influencing factor is the optimism bias or unrealistic optimism. It refers to the thought many people hold that bad things (e.g. road traffic crashes) will not happen to them personally.

The Process behind Driver Behavior

Why and how people behave as they do

How a driver perceives a risk, so his or her subjective impression of risk in a specific driving situation is relevant to understand a drivers behavior. So called “Risk Models” help us to understand the predictors of risk-taking behavior.

Wildes Risk Homeostasis Theory

Wildes Risk Homeostasis Theory for example argues that each driver has a certain individual risk level that he or she is willing to accept when on the road. Drivers are supposed to adjust their behavior according to this risk level. So if the personal risk is for instance decreased by safety belt use, drivers will compensate this by e.g. driving faster, namely increase the risk so that it matches their personal risk level again.

A downside of Wildes Risk Homeostasis Theory is that it is difficult to verify since it is hard to measure if drivers indeed adjust their behavior as the model proposes. In addition it disregards any other factors, like personality.

Risk-Allostasis Theory

A more holistic approach is the Task Difficulty Homeostasis Theory which is nowadays called Risk-Allostasis Theory. This theory argues that drivers have a preferred level of task-difficulty as well as feeling of risk. It is assumed that drivers adjust their behavior in a way that the driving demands do not exceed their capabilities at any point in time. An example for this might be when we stop talking with our passengers as soon as the task of driving becomes more demanding. Allostasis means to strive for stability by making behavioral adjustments.

Tools for Data-collection

Driving simulators

Most of the times self-reported measures are used to gather information about driving behavior. Driving simulators and direct or naturalistic observations are often preferred for assessing driving skills, driving behavior and driving performance.

Driving simulators are machines that simulate the real driving process. Participants should feel and act as they would while driving a real car on the road. Examples for this are instrumented vehicles which are vehicles equipped with data collection tools for on-road assessment of driving behavior.

An advantage is that driving simulators enable researchers to control for variables which are usually uncontrollable for in traffic like weather conditions or the ongoing traffic. By this it leads to high controllability, standardization and reproducibility.

Additionally it avoids any physical risks so researchers can manipulate for dangerous driving situations to gain insight in the driver’s reactions. It is also possible for the researchers to give feedback and instructions while the experiment is going on.

On the other hand it is questionable how valid the outcomes of such driving-simulator studies are. Since it is hard to say to what extent the participants who are put into a dangerous situation really feel the anxiety they would on street. Therefore ecological validity might be low.

Direct and Naturalistic observations

A direct and naturalistic observation involves observing the driving behavior of people directly on the road. This way it is possible to collect objective data free from problems with biases which might be caused by social desirability or self-representation. These terms mean that people want to be seen in a positive way and therefore might adjust their answers accordingly. These are common problems in self-reported measures.

While doing a direct or naturalistic observation researchers have to watch out for sampling biases. Since driving behavior might differ from neighborhood to neighborhood as well as from day to night time, observers need to work at several times and places to gather valid information. A drawback of this method is the high costs that are needed for all the human resources involved.

The advantages of valid data collection usually overweigh the presented disadvantages of direct and naturalistic observations. In general researcher could also look at already collected data to gain insight about what might be worth investigating in future.

Interventions

Interventions are procedures used to enhance the safety behavior on the road.

Before drivers are allowed to become part of the road traffic they have to undergo driver’s education. Driver’s education helps them to understand and learn the rules of the road and to acquire driving skills.

Graduate driving laws (GDL) limit the driving types allowed to be performed by unexperienced or younger drivers.

One well known intervention technique to reduce rules violations is enforcement. It delivers punishment as soon as an officer or technology tool (e.g. camera) has detected rule violations. Since it works with learning theory it should reduce reoccurrence of the target behavior. But since many violations are not detected most people return to their behavior even after enforcement.

Learning theory works with punishment to reduce the occurrence of a specific behavior and with reward to enhance the occurrence of a specific behavior. Therefore an addition of reinforcement-based approaches to enhance safe driving might be a more holistic approach.

Persuasive messages

Persuasive messages in a safety driving context focus mainly on impaired driving, seat-belt use or distracted driving. It aims to persuade people to drive more safely. Persuasive messages are in general most effective when they are targeted to their audience.

Shared spaces

A pilot project that is performed in some cities is called shared spaces. This means that all road users share their spaces in the absence of any signalization (e.g. traffic lights, stop signs). Studies have revealed that this has actually a positive effect on traffic safety since it forces each traffic user to be highly attentive and considerate.

Applied Social Psychology in context

Collaborations between social psychologists and road-designers, engineers, urban designers as well as car companies and policy makers could benefit driver’s safety.