"A fundamental premise of government and industry policies is that it is possible to reduce the rate and severity of accidents by improving the design of machines and the environments in which they are used, and increasing the skill of their human operators. Wilde's theory of Risk Homeostasis constitutes a frontal attack on this premise and, accordingly, on the safety measures based on it. Wilde is to be congratulated for carefully and explicitly setting out a fascinating theory of risk-taking behaviour. In addition to its theoretical interest, his proposal has important practical implications, making it worthy of detailed, critical examination...Wilde's theory is a novel application to health and safety of the homeostatic concept."

Paul Slovic and Baruch Fischhoff, Decision Research, Eugene, Oregon

"Antilock braking systems, airbags, seatbelt laws, traffic lights, speed regulations, are all part of mammoth efforts to reduce traffic casualties. But do these measures, and their counterparts in industry and public health, have the effects intended? In his theory of risk homeostasis, Professor Gerald Wilde postulates that they don't, because they fail to influence people's willingness to take risk.

Now, for the first time, Wilde collects his famous theory, along with its supporting argument and data, into one fascinating document. Target Risk is a powerhouse of insights into human risk-taking behaviour. It's a book that everyone interested in safety and health promotion should have on their shelf."

"The basic idea of risk homeostasis has been laid out brilliantly by the Canadian psychologist Gerald Wilde in his book ‘Target Risk.’"

"The best-known model–but also the most controversial–is Wilde’s ‘homeostasis of risk’, in which risk perception and risk utility are integrated in a single cybernetic conceptualization."

"…the ideas suggested by Wilde have important implications for anyone who must manage risks."

"The risk homeostatic approach, the devil’s idea to some in the safety community....Human behaviour is the dominant force in the risk homeostatic approach. Technological changes will be completely offset by user response unless the target level of risk is changed."

".....the question of risk homeostasis and its existence is like the question of whether or not God exists...."

"The model may be taken as a simple, plausible, and appealing device and, viewed from that perspective, Wilde’s theory has much to recommend it."

"…[Wilde] is probably the most prolific researcher and writer in the area of danger compensation or risk-offsetting behavior…"

"Wilde’s diligent, eclectic search for empirical data to support his theory of risk homeostasis is exemplary. His efforts have served as a focal point of debate and have led others into theory-based discussion relevant to driver behaviour…"

"…there are no epicycles and there is no phlogiston…similarly, there is no risk homeostasis."

"As Evans has noted [risk homeostasis] commands about as much credence as the flat earth hypothesis."

"And increasingly, the evidence suggests that Wilde is right."

"…Gerald Wilde, the man with the original idea....The Wilde hypothesis suggests an explanation: protecting car occupants from the consequences of bad driving encourages bad driving.....there is one form of safety legislation which Risk Homeostasis Theory suggests will be futile: legislation to protect people from themselves.....the principal, and perhaps the only, determinant of aggregate accident rates is what Wilde calls the ‘target level of risk.’ "

"Fundamental questions are asked about our public approaches to coping with risk."

"The effect of Mr. Wilde’s theory would be a concludsion that nothing works when it comes to traffic safety, which is why critics have labelled it ‘Wilde’s Law of the conservation of Misery.’ But it does express some degree of truth since people aren’t just robots, they do adapt their behavior to changed circumstances."

"Any attempt to answer whether or not we are implementing the right safety measures must address the controversial issue of ‘risk homeostasis.’"

"Penny-pinching bosses take note: a well-implemented incentive program can pay for itself several times over due to lower absenteeism, higher productivity, and reduced insurance and workers’ compensation premiums. Says Wilde: ‘For marginal companies, the payback may be large enough to enable them to stay in business."

"In general, our roads have become safer over the years. Knowing this, most drivers drive farther and faster because they perceive low risk. As a result, purely technological improvements fail to reduce the number of deaths."

"Possibly the most provocative statements were put forward by the Canadian psychologist Gerald Wilde....the accident rate per kilometre driven has fallen, but not so the accident rate per hour of participation in traffic.....every society has the accident rate it is willing to accept."

"......’risk homeostasis theory’.............a misnomer......."

"Wilde has a whole book full of real-life examples of how we all set a risk target and adjust our behavior accordingly. Adding anti-lock brakes to a car, for example doesn’t reduce accidents. Aware of their greater braking ability, drivers follow more closely and drive faster on slick streets.......depressingly, Wilde concludes that we get the safety we deserve. If Canadians truly wanted a lower accident rate, they would simply change how they drive....if you doubt, read the evidence yourself in Gerald Wilde’s Target Risk."

"Risk compensation is not a consequence of an indomitable desire for risk, but simply follows from an economic principle."

"Wilde has made a name for himself in risk analysis. A close study of traffic accidents and human behavior led him to develop his controversial theory of ‘risk homeostasis’....new safety measures don’t create a safer world."

"The homeostatic theory of risk and its implications for traffic safety is in part revolutionizing and destroying many of the conceptions that until now have been held by traffic authorities in many countries"

"Expert calls road blitz useless. Says accidents will migrate to nearby roads."

"Wilde illustrates his mental bagage with provocative brain teasers. For instance, the solution of the problem of a dangerous road is just to close it. But the accidents will surely migrate elsewhere; so, that’s not an effective solution. Why, then, should you prohibit driving under the influence?"

"Based on the notion that rules don’t force us to drive more safely, this radical theory suggests rewarding good drivers is more effective than punishing bad."

"The notion of risk homeostasis crops up constantly - in letters to the editor, in scientific articles, and political debates."

"A risky adventure.......Road safety specialist crosses through São Paulo and finds a ‘jungle.’"

"G. Wilde .......lays out the implications of risk homeostasis theory for traffic safety education."

"[Wilde’s] theory about ‘Target risk’ or ‘The risk that people accept’ has caused a polemic and made an invaluable contribution to the study of human behaviour in situations of risk."

"Recent studies by a Canadian psychologist strongly suggest that even the best get-tough campaigns to reduce alcohol-related driving accidents fail because they ignore basic principles of human behavior......To say that alcohol is a cause of the accident rate is to say there was no war before the invention of gun powder, ....that the demon is in the bottle, not in the man......Programs that offer rewards for behaving safely, rather than penalties for taking foolish risks, stand the best chance of reducing teen-age drunk driving accidents over the long term."

"Wilde asserts that every society has a buit-in "target level of risk" that constitutes the level of danger people are willing to accept in exchange for the benefits they believe they accrue, such as getting to work on time or deriving pleasure from driving. This target level functions as a kind of danger thermostat: Devices that make drivers safer, he argues, provoke a collective increase in risky behaviour."

"Automobiles: the risk we accept. Some experts claim our safety programs falling short of aims."

"A common snake in the grass is the hypothesis of constant risk that was developed by the expatriate Dutch psychologist G.J. Wilde"

"There is no end to them. If the road is made wider and safer, we drive faster.....Life’s little gambles."

"Why more condoms may not contain the spread of Aids......Risk compensation raises awkward questions about advertising aimed at selling safety products."

"In mutual-fund investing, reality comes when net asset values get clobbered and don’t recover for a very long time. That’s when people begin to calculate what they have lost and what they continue to have at risk. That is when the urge to sell turns into an inner primal scream, a panic to save what’s left of an investment."

"Professor Wilde is considered to be the leader in contemporary traffic psychology."

"...Risk homeostasis provides a comprehensive theory of human behaviour, and in doing so provides a useful framework for discussion and development of research......Wilde’s writing is coherent and clear and should be accessible without prior exposure to the traffic safety literature."

"A deeper understanding of the motivational barriers that frustrate injury prevention measures is critical to the advancement of our field. Professor Wilde makes a lasting contribution by shedding some light on this neglected area."

"A provocative theory, a wide variety of evidence, some interesting anecdotes, and a colourful writing style; with these ingredients, Gerald Wilde has composed a book that entertains the reader, but also presents him or her with a comprehensive theory about the psychological processes that underlie risky behaviour......."Target Risk" convincingly establishes that people are inclined to counteract expected changes in risk. For safety engineers and risk managers, this implies that it is naive to design safety measures under a ‘ceteris paribus’ assumption regarding human behaviour. Unless a measure succeeds to lower their ‘willingness to take risk’, people will always find ways to convert the potential safety gain into a gain in, e.g., time or money. Wilde not only succeeds in explaining and demonstrating this mechanism in a clear and convincing way, he also anchors it in an elegant theory and offers a thorough discussion of the practical implications."

"....what is of enduring significance in the work of Wilde is the proposition and evidence that safety measures which reduce the accident rate per km driven do not necessarily increase safety per time unit of exposure or indeed safety per head of population. Safety measures are sometimes consumed by increased mobility and may encourage greater exposure to risk."

"A superlative achievement in the professional literature."

"In simple terms, Wilde’s theory suggests that when we engage in valued but risky behaviour we automatically adjust our behaviour to a target level of risk.......Target Risk contains forceful arguments to look carefully at claims about the effects of measures to increase public health and safety."

"When Gutenberg meets Cyberspace.....In the 15th century, Johannes Gutenberg took a risk and published the first mechanically printed bible. Now, a book about risk-taking and a publisher willing to take a chance have become pioneers in the world of online publishing.....’Target Risk’ is one of the first books released simultaneously on the Internet and in print.....What I enjoyed about the online version of "Target Risk" was that it was like thumbing through a real book in a real store. I could take a few minutes and see if I liked the book before shelling out some money."

"The essence of Wilde’s theory is that individuals manage their own risk by a feedback control loop which seeks to maintain the risk they perceive near a target risk level, much like a thermostat control loop maintaining building temperature near a desired set point. Although this model may seem too mechanistic for addressing the complex range of human behaviours associated with risk, Wilde presents strong arguments for the utility of his theory."

"Are cigarettes that are half as carcinogenic better for public health than the cigarettes we smoke today? No, that is not so certain according to Dr. Wilde. How many people who now want to quit would continue to smoke? How many current non-smokers would start smoking the not so dangerous cigarettes, and how many current smokers, used as they are to the present risk of cancer, would not hesitate to smoke twice the number of cigarettes? Maybe such a new cigarette poses a major danger to public health."

"Making things safer can be a risky business ...... Professor Wilde responds that because his theory focuses on motivation it emphasizes the positive. Instead of viewing human beings as passive subjects of technical designs or enforcement, we should treat them as active subjects and look for ways to make them want to be safer."

"Are seatbelts and bicycle helmets meaningless safety measures? That is what Gerald Wilde maintains on the basis of his Risk Homeostasis Theory. He agrees that it is good to have them in the case of an accident, but as road users know this, they exploit them by taking more risk or by increasing their exposure to traffic. The end result is that the number of dead or injured in traffic does not change."

"In his book Target Risk, Professor Gerald J.S. Wilde lays out his famed Theory of Risk Homeostasis as a potential explanation for why people behave as they do in relation to risk. His theory constitutes a frontal attack on the premise that the rate and severity of accidents can be reduced by improving the design of machines and environments."

"Wilde has a whole book full of real-life examples of how we all set a risk target and adjust our behavior accordingly. Adding anti-lock brakes to a car, for example doesn’t reduce accidents. Aware of their greater braking ability, drivers follow more closely and drive faster on slick streets.......depressingly, Wilde concludes that we get the safety we deserve. If Canadians truly wanted a lower accident rate, they would simply change how they drive....if you doubt, read the evidence yourself in Gerald Wilde’s Target Risk."

"Our highways are getting better, our cars safer, and we are now spending millions of dollars annually on road safety campaigns. Why, then, is the road toll not coming down faster? Researchers believe they may have found the answer......Thus, if the theory is correct, giving people better-handling cars will encourage them to corner quicker. Give them better brakes and they will follow more closely. Give them better roads and they will drive faster.... Dr. Wilde goes as far as to argue that the "three E’s" -- enforcement, engineering, and education -- do not improve road safety across a whole population..... Risk homeostasis [...] is the road safety equivalent to the theory of continental drift."

"The Theory has greatly contributed to the progress of safety research......"

".... the dominant influence....... in the last two decades has been that of the Canadian psychologist, Gerald Wilde."

"Making an activity safer may increase mortality."

"Possibly the most provocative statements were put forward by the the Canadian psychologist Gerald Wilde....the accident rate per kilometre driven has fallen, but not so the accident rate per hour of participation in traffic.....every society has the accident rate it is willing to accept"

"Can science make trucks safer? Yes and no, Gerry Wilde says. Yes, if the science is psychology. No if it’s anything else..... His ideas upset a lot of psychologists, not to mention truckers, law-makers and technologists."
Andy Turnbull, Truck News

"A veritable flood of criticism.......has been directed against the theory of risk homeostasis (RHT).... Rejoinders have invariably criticized the critics for their misunderstanding of RHT and their selection for inappropriate data to test it."

"The pseudo-scientific notion of ‘risk homeostasis’….. The dutch-calvinist preacher of this belief is telling us that the danger is not outside in the surrounding world, but in the road-user himself…..The road-user is the great sinner who is responsible for all misery. These moral and religious prejudices…….related to the pseudo-scientific freudian notion of pervert death-wish."

"The present demerit system …..tries to to capitalize on the notion of pushishment and is psychologically unsound: punishment at best produces only a temporary suppression of undesirable behaviour while a reward system leads to lasting behavioural change. Or, as grandma used to say, sugar will catch more flies than salt."

"Does risk homeostasis theory represent a serious threat to ergonomics? ....Risk homeostasis theory is a pessimistic theory.....Wilde argues that ergonomic measures are useful in increasing mobility but they are not useful in saving lives......There is nothing unique about the argument that increasing the desire to be safe may be a significant safety measure. What is unique is the argument that it is the only significant safety measure."

"Does Wilde manage to convince? It is not the role of a book review to lead readers to conclusions. Rather I should say that whether what he claims is right or not, I have benefited from reading Wilde."

1999.03.05

Visitors since July 21, 1998