You probably know a risky type. He rides like the devil on amphetanmines regardless of the road conditions. Worse still, he disregards every rule - law or common sense - barrelling at balls - out pace into blind bends, forcing cars to avoid his banzai overtakes, and leaving you with your heart in your mouth. We've all at some point witnessed the riding of a fearless idiot - and prayed his stock of borrowed time doesnt run out too soon.

At the other end of the scale, Mrs Safety First takes every precaution available; she opts for ABS and fluorescent kit, spends her weekends taking extra training, and rarely if ever breaks a speed limit. These two riders have polar-opposite attitudes to risk. But why? How come some people ride headlong towards danger while others do everything they can to safequard their safety?

Answering this question is like the quest for the Holy Grail for road safety experts. Despite the crumbling authority of gods, accidents very rarely just happen as a consequence of random chance or bad luck; they occur when people take unnecessary or poorly calculated risks. We cant understand these mistakes without unlocking the secrets of motorists' thought processes. The problem is, its very tough to account for bad decisions like "Why did I ignore that Mud on Road sign?" because mistakes are, almost by definition, beyond rational explanation.

The psychologist called Gerald Wilde theorised that we each have our own sensitivity to danger and each take steps to keep risk at a constant level. According to this theory of 'risk-compensation', if we think the road surface is dry and grippy, we automatically leave shorter stopping distances than when conditions are slippery -maintaining the same level of risk. This means that all safety measures prove useless bacause we counteract them by riding more dangerously. For example, if we know a corner is surfaces with high-friction 'shell grip' Tarmac, we'll attack it with knee-down zeal every time.Similarly, if the SHARP Scheme convinces us that our helmets are super-safe, we'll be more blase about risking our heads. "If [Wilde's theory] is correct," explains Dr Graham Hole, "it is possible reduce accident rates only by increasing peoples desire to be safe: they have to want to change their target level of risk."

Its tempting to dismiss Wilde's theory by pointing out that some safety improvements, such as the introduction of crash helmets, have obviously worked and saved many lives. The trouble is, interpreting accident data is never sstraightforward; its hard to conclusively attribute a reduction in fatalities to any single factor. There are always many variables which may or may not have played a part.

The killer question for risk-compensation theory is: Are we really able to rate our own risk? There is a wealth of evidence that suggests we're actually very bad at judging the dangerousness of travelling by road. Take the brain-out rider described above; he seems completely oblivious to the riskiness of his actions - and probably wont come to his senses until he first comes to grief. For most of us, in fact, day-to-day life on the road feels quite safe. This is not loony optimism, but the sum of our experience; a sense of safety accrues gradually over the hundreds, if not thousands, of journeys completed without incident. We know that crashing doesnt happen very often. Our sense of danger is based on first-hand experience, not second-hand statistics. We're liable to worry more about crashing when we travel by less familiar means - on a plane, for instance - even though the probability of an accident is far lower (1.5 crashes for every million departures).

Riding in conditions like this you’re much more likely to crash right? Not necessarily. It’s so bad you’re forced to respect the conditions, slow down and take more care. If it was dry you’d possibly be going much too fast and scraping your slider on the road, so although the conditions are much different, the element of risk is just as high.

The dangers of the road simply don’t stick in our minds. Research suggests that we tend to forget very quickly the near-misses we have, and all but the most frightening close-calls fade from memory within about a fortnight. Combine all these factors together, and it’s clear that our inbuilt risk-radars are unreliable at best, downright misleading at worst.

It isn’t just that we miscalculate risk; we also have an infl ated sense of our own abilities to deal with the hazards we encounter. Dr Hole describes the results from a 2004 survey: “[Most] drivers rated themselves as slower, more skilful, safer, and less likely to have an accident than their peers or the ‘average’ UK driver.” An additional tendency has been observed whereby drivers attribute their own mistakes to external factors (“It was a patch of diesel, honest”), while blaming other people’s errors on personal traits (“He ran out of talent, the half-wit”). The accident is always the fault of something or someone else. There is more to this than excessive pride. On a single journey, we see hundreds of other drivers, and the chances are one or two will make a mistake while we’re watching them. This gives us the impression that other drivers are more error-prone than ourselves. After all, no one ever observes their own driving, and motorcyclists don’t even have backseat critics. The worst drivers are the least self-critical. This fl ies in the face of risk-compensation theory; awful drivers don’t assess their risk by offsetting dangers against safe practices, but rather amass bad traits like badges of (dis)honour. You’ve probably had a run-in with this type – they never wear seatbelts, always speed, drive under the infl uence, and speak on the phone while fi ddling with their stereos, etc, etc.

You might expect the most skilful drivers to be the safest, but various studies have revealed that those who rate their skills highly also take more risks. Indeed, there is no proven correlation between vehicle-control skills and accident rates; in one survey, racing drivers who drove on public roads were shown to have more accidents than normal drivers. The ability to go very fast around a racetrack is not what keeps you safe on the road (one reason, perhaps, why many bike racers choose not to ride on the road).

Of course, an over-confi dent racer probably won’t crash in the same way as a panicky pensioner. There are many different types of risky behaviour but they can be loosely divided into two categories: unintentional mistakes (e.g. failing to notice a stop sign) and deliberate violations (e.g. ignoring a stop sign). Surveys have shown that women make more errors than men, but men commit more violations; and men have more crashes overall. Although this gender difference is anecdotally interesting, it doesn’t tell us much about why some people have more crashes than others. Who are the riskiest drivers on the road, and why?

Is there a type of person who’s more likely to drive dangerously? We know that men aged 17 to 25 have proportionately more crashes than any other group, but does this relate to their personality traits? One theory is that young males are more dangerous because they have a thrill-seeking attitude to driving. Then again, the desire to savour the sensation of speed is a big part of the joy of riding a bike, whether you’re young or old. Driving or riding for the feeling of it can be enjoyable for several reasons: it’s novel and refreshing; it obliterates boredom; and it gives a feeling of release from the restraints of convention or self-control. Thrill-seeking carried out for the latter reason is, according to research, the most hazardous because it manifests as a careless disregard for rules. However, it’s still very tricky to pick out dangerous drivers based on character traits because quirks of personality aren’t static or predictable; thrill-seekers don’t always drive carelessly, and non-thrill-seekers don’t always stick to the rules. Another characteristic that’s thought to be dangerous is anger – and its knock-on effect, aggression. Again, men have been shown to be more susceptible to getting in a rage while driving. There’s no easy way, though, to establish whether driving-aggressiveness is a personality trait or something brought about by circumstances; even people who are generally calm can lose their cool if provoked. What’s more, psychologists have exposed as a cliché the notion that usually-reasonable people turn into brutes once behind the wheel. “This is unlikely,” says Dr Hole, “[the] data suggests that the relationship between anger, verbal and physical aggression, and driving is complex, and that different situations give rise to different patterns of anger or aggressive response.” There is a multitude of reasons why motorists take unnecessary risks, but most do something careless or foolhardy every now and again. The most valuable lesson from psychological research is that it pays to be modest, keeping a critical eye on your own riding skills, attitudes and habits. Let’s face it, there’s little point blaming other drivers for the dangers you face, as there’s not a lot you can do to modify their behaviour. If you’re riding fast and/or breaking the law, ask yourself whether you’re doing it for the right reasons, within your abilities, and under suitable circumstances. You may have been lucky so far, but don’t get complacent. Take responsibility for your safety by setting a realistic margin for error which accepts that mistakes befall everyone, even the most skilful.

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