Apr
13
2012

Post hoc, trees are dangerous

Last night (11/4/2012) I took part in an interesting Radio 3 discussion programme called Night Waves . The first contributor, Jonathan Haidt, was fascinating and I’ve just ordered his new book The Righteous Mind.

In the discussion he made a point that resonated with a problem that I have been wrestling with: discussing the relationship between reason and emotion he said, “reason is mostly post hoc”. Risk management decisions are taken pre hoc. They are decisions taken with insufficient information. They are decisions about an uncertain future. Post hoc, after the event/accident, there is usually much more information to which one can apply cause and effect reasoning. Before the event the links between causes and effects are either unknown or shrouded in estimates of probability, with large error bands attached. The information gap confronting a risk manager is readily filled by “emotion” – the natural instinctive state of mind deriving from one’s circumstances, mood, or relationships with others.

Event Trees, beloved of engineers and project managers as a method for describing the risks associated with big projects, represent a denial of this reality (see Dangerous Trees?). All of the branching points on each limb of their trees must be assigned probabilities, usually with large error bands. By the time one reaches the tip ends of the branches the compound error bands are too large to fit on the page, so the magnitude of the uncertainty is ignored.

In the dangerous trees example just referred to an actual tree blew down and killed some one. In Britain, averaged over the whole country, the statistical risk of such a thing happening in a given year is about 1 in 10 million. Britain’s Health and Safety Executive describes risks of 1 in 1 million as “adequately controlled”. But after the event different sorts of reasoning are brought to bear. The police, who are predisposed to allocate blame in such circumstances, arrested the head estate warden and the estate manager on suspicion of negligent manslaughter. The coroner declared, a year and a half later, that all mature trees on the estate’s land adjacent to paths should be inspected and logged – a requirement that, if applied to all the National Trust’s properties (whose estate it was) might have bankrupted the institution.

Post hoc Event Trees are often transformed into Fault Trees that, with the aid of clear facts and “reason”, are transformed into trees with only one branch called “culpable negligence”. What pre hoc appeared a risk of 1 in 10 million, post hoc becomes a risk of 1 in 1.

After a year and a half the Crown Prosecution Service, dropped the case for lack of evidence, but a threat of dire consequence still hangs over the National Trust. Given the many millions of mature trees in Britain, the risk assessment and risk management implications of the coroner’s judgment, pursued to their logical conclusion would require the diversion of enormous resources to inspection and/or the execution of countless mature trees that could not be guaranteed 100 percent safe – and who would offer that assurance in our litigious times? This experience is now colouring the (emotional?) judgment of Britain’s tree managers. In deciding what trees must be executed the legal risk now far outweighs the physical risk.

Feb
22
2012

ISO 31000: Dr Rorschach meets Humpty Dumpty

Much advice is proffered in cyberspace about how to manage risk: at the time of writing, tapping “risk management” into Google yielded 72 million hits. Do you sometimes (frequently?) on reading risk management guidance get to the end without a clue as to what the guide expects you, the risk manager, to actually do?

I am currently having this problem with ISO 31000 – Risk management — Principles and Guidelines. The International Standards Organization published these guidelines in 2009 and with them appears to aspire to global leadership, if not domination, of the risk management industry. According to Kevin Knight, leader of the group that produced the document, it is comprehensive and global in reach – it “provides principles and practical guidance to the risk management process” and it applies to everyone everywhere – it is “applicable to all organizations, regardless of type, size, activities and location and should apply to all types of risk.”

A game anyone can play
I have now read it many times and still do not know what is expected of me. And I think I have worked out why. It repeatedly tells me to do what is “appropriate”: it tells me that my involvement with stakeholders should be “appropriate and timely”; that I should consider “the most appropriate ways to communicate with [stakeholders]”; that I “should allocate appropriate resources for risk management”; and that I should “communicate and consult with stakeholders to ensure that [my] risk management framework remains appropriate.” The guidance to do the “appropriate” thing appears 34 times in 26 pages.

What is “appropriate”? Those deploying the word appear to assume that all readers will share its meaning. But anyone plugged into discussions about the influence of disparate cultural perceptions of risk will appreciate that this is a facile assumption. All these “appropriates” are Rorschach inkblots. The famous Rorschach test is known as a projective test. Subjects are shown ambiguous stimuli (inkblots) and asked to say what they see. Although psychologist have failed to reach a consensus on the interpretation of the answers it is clear that different people project very different meanings onto ambiguous stimuli.

“Appropriate” is not the only inkblot in ISO 31000. There are 33 “effectives” (“this International Standard establishes a number of principles that need to be satisfied to make risk management effective.”); 13 “culture/culturals” (“Risk management takes human and cultural factors into account.”); 9 “relevants” (I should ensure that “risk management remains relevant and up-to-date”); 8 “comprehensives” (I need “to generate a comprehensive list of risks”); plus 4 “acceptables” and 4 “tolerables”.

Using this (incomplete) list of inkblots I divide 105 inkblots by 26 pages and award ISO 31000 an inkblot score of 4.03. It is a game that anyone can play and I offer it as a way of quantifying the sense of vague dissatisfaction generated by so much of the current risk management literature.

Humpty Dumpty
Humpty famously told Alice “When I use a word it means just what I choose it to mean — neither more nor less.”

One word in ISO 31000 is most definitely not an inkblot. “Risk” is defined as “the effect of uncertainty on objectives – positive and/or negative”.

The document is forcefully determined that the meaning of the word should be absolutely clear to all readers. Section 2 contains 29 terms and definitions elaborating on the meaning of “risk” and its use in the document – supplemented by 44 explanatory notes. Section 3 contains eleven “principles” that turn out to be further definitions, e.g. “d) Risk management explicitly addresses uncertainty.”

But all this is not sufficient. To be absolutely confident that one is on the ISO 31000 wavelength one must master Risk management – Vocabulary (ISO Guide 73:2009). This is a 15-page dictionary further elaborating the terms and definitions of ISO 31000. An example: ISO 31000 refers to “stakeholders”, but one needs the ISO vocabulary to be confident of knowing what this word means – “a person or organization that can affect, be affected by, or perceive themselves to be affected by a decision or activity”. The Guide provides 49 such examples (supplemented by 56 more notes).

The ISO definition of risk – “the effect of uncertainty on objectives – and/or negative” – is described by the leader of the group that produced it, as “pivotal”. Certainly it is the pivot, the authors are determined, around which all discussion of risk management should rotate. But they have a couple of problems.

The first is that their definition of risk as something “positive and/or negative” is shared by no other dictionary. “Risk” as the rest of the world uses the word is negative. It is
• · “the possibility that something unpleasant or unwelcome will happen (http://oxforddictionaries.com/definition/risk) , or

• · “A probability or threat of a damage, injury, liability, loss, or other negative occurrence that is caused by external or internal vulnerabilities, and that may be neutralized through preemptive action” (http://www.businessdictionary.com/definition/risk.html ), or

• · “possibility of loss or injury : peril, someone or something that creates or suggests a hazard” (http://www.merriam-webster.com/dictionary/risk)

The established dictionaries have the merit of defining words as most people use them. With its idiosyncratic definition the ISO appears to aspire to establish itself as a priestly caste with a private vocabulary inaccessible to the vulgar horde.

There has been an attempt by ISO supporters to gain a foothold in other dictionaries. The Wikipedia definition of risk is in agreement with the established dictionaries: “Risk is the potential that a chosen action or activity (including the choice of inaction) will lead to a loss (an undesirable outcome).” (http://en.wikipedia.org/wiki/Risk).

But then an ISO enthusiast took advantage of Wikipedia’s open-editing facility to add the following: “The ISO 31000 (2009) /ISO Guide 73 definition of risk is the ‘effect of uncertainty on objectives’. In this definition, uncertainties include events (which may or not happen) and uncertainties caused by a lack of information or ambiguity. It also includes both negative and positive impacts on objectives. Many definitions of risk exist in common usage, however this definition was developed by an international committee representing over 30 countries and is based on the input of several thousand subject matter experts [my emphasis added].”

The ISO definition may well be now shared by several thousand linkedin “experts”, but the problem is that they are vastly outnumbered by the hundreds of millions of other lay and expert risk managers who share the dictionary meaning – who understand risk to be something negative. From Britain’s Health and Safety Executive (mantra “Reducing Risks, Protecting People”) to the quants who calculate Value at Risk, most risk experts still side with the dictionaries. The consoling mantra of day traders after a bad day is “No risk, No Reward”. Outside the ISO club risk means what the dictionaries say it means.

A second problem encountered by the “expert” advocates of ISO 31000 is that their job as risk managers involves communicating with non-experts. Their definition of the key word “risk” that will be central to these communications is not only not in the dictionaries that most of the non-experts are likely to consult, but can be found only in ISO 31000 and the supplementary vocabulary ISO Guide 73. These documents cost CHF 112 ($104) and CHF 86 ($80) respectively.

When Alice questioned the meaning of a word that Humpty Dumpty had used he replied, “The question is which is to be master — that’s all.” In attempting to assert its mastery over the word risk, a word requiring 178 expensive terms, definitions and notes before those deploying it can be confident that they know what they mean by it, the ISO experts face a challenge. “When I make a word do a lot of work like that, said Humpty Dumpty, I always pay it extra.” Payment is likely to take the form of tears of frustration.

ISO 31000 and the IRM
In 2010 the IRM published an endorsement of ISO 31000 in a document entitled A structured approach to Enterprise Risk Management (ERM) and the requirements of ISO 31000. It says “this guide [the IRM Guide] provides a structured approach to implementing risk management on an enterprisewide basis that is compatible with both COSO ERM and ISO 31000.”

It runs into an immediate problem. ISO and COSO cannot agree on the meaning of the word at the centre of the exercise – “risk”. COSO sides with the dictionaries and views it as negative – “the possibility that an event will occur and adversely affect the achievement of objectives” while ISO defines it as “positive and/or negative”. Humpty Dumpty has yet to pronounce.

The IRM document shares with ISO 31000 an impressively high inkblot count – words onto which readers will project variable subjective meanings. In 17 pages it has 21 “appropriates”, 16 “significants”, 14 “effectives”, 14 “culture/culturals”, 13 “effectives”, 7 “comprehensives” and 4 “sufficients” – yielding an inkblot score of 5.3 – or 36 if you add the 523 occurrences of “risk” which, thanks to the ISO/COSO definitional conflict, has itself become an inkblot. The sentence “Achieving a good risk aware culture is ensured by establishing an appropriate risk architecture” conveys the flavour of the difficulty confronting those seeking to standardize risk management guidance. Which definition of risk will the health and safety officer, investment banker, compliance manager, financial regulator, or teacher producing a risk assessment for a school trip, have in mind when reading this sentence?

Although “culture” appears liberally in both documents it is used without content. There is no apparent awareness, acknowledgement or application of the substantial literature by behavioural economists, psychologists, anthropologists and members of other academic disciplines on the influence of cultural biases. The subtitle of the seminal work Risk and Culture, by Douglas and Wildavsky almost 30 years ago is “An Essay on the Selection of Technological and Environmental Dangers”. Ever since then cultural influences on the threats that people select to worry about, or choose to ignore, have generated an impressive literature. Why are GMOs shunned in Europe while planted over millions of acres in the United States? Why do middle-aged women have much lower road accident rates than young men? Who worries about global warming, and why? And what induced some derivative traders to place bank-busting bets? ISO 31000 appears oblivious to such questions. Why?

In an article in Risk Analysis Grant Purdy, one of the principal architects of ISO 31000 describes it as “a new globally accepted standard for risk management”. Accepted globally? Accepted by whom? Most, the vast majority, of the people around the globe interested in risk management have never been asked. They have never read it, and probably never heard of it. The academic world is comprehensively ignorant of it because it can be found in no libraries. If it, and its associated vocabulary, were to be made available in libraries sales of these documents at CHF 198 would be severely compromised.

No academics I know are likely to pay such a sum for the privilege of reading them. For a start they would not be interested in writing about something almost none of their colleagues had heard of – I have only been able to join this discussion because an anonymous friend sent me bootleg copies.

The academic world depends on open access to sources. The IRM is so sensitive to ISO’s aggressive protection of its copyright that it declares in its introduction that “Permission to reproduce extracts from ISO 31000 ‘Risk management – Code of practice’ is granted by the BSI.” Academics are not in the habit of seeking permission to reproduce extracts from sources that they are commenting upon.

Purdy acknowledges that ISO 31000 creates “challenges for those who use language and approaches that are unique to their area of work but different from the new standard and guide. The need for compromise and change is” he insists “the inevitable consequence of standardization.” In a world where the vast majority use approaches that are free, and communicate in the language of the standard dictionaries, the unique approach and language of the ISO “new standard” appear unlikely catch on.

Jan
13
2012

What is risk?

A new book from Cambridge University Press – Successful Science communication, (Bennett and Jennings eds.) – contains 26 chapters with helpful things to say to people concerned to communicate complex ideas to “the public”. Plus a chapter by me entitled Not 100% sure? The “public” understanding of risk; the reader is left to judge whether it too is helpful.

It begins: “Where knowledge (belief) relates to potential future harms or benefits, as it usually does in situations where science communication is seen as problematic or contentious, the issue can be framed as one of risk communication.”

And concludes: “The problem for science communicators is that we, scientist and non-scientist alike, do not respond blankly to uncertainty. We impose meaning upon it. The greater the uncertainty the greater becomes the influence of perceptual biases. These biases have deep cosmological roots and are not easily shifted. Perhaps the best that a science communicator can hope for is that introspection might assist recognition of one’s own biases, and an awareness of the inevitability of different biases in others. Self-knowledge and an ability to stand metaphorically in the shoes of others are key ingredients of the empathy essential to effective communication.”

And the first section is headed “What is risk?”

Jan
08
2012

Thinking Streets

A recent BBC radio 4 programme entitled Thinking Streets takes listeners on a refreshing tour of traffic management schemes that are elevating the status of pedestrians and cyclists relative to that of those in motor vehicles. The effect, as researcher/presenter, Angela Saini notes, is civilizing – while also reducing accidents. The programme features Ben Hamilton-Baillie, who it rightly describes as Britain’s “biggest advocate of shared space”. He is also a very convincing advocate with a website worth visiting. I have a brief part in the programme explaining the concept of risk compensation.

In Where and when is shared space safe? (PDF) I introduce the concept of shared space as follows:

Traditional highway engineering assumes that safety requires the spatial segregation of pedestrians, cyclists and motorized vehicles or, where this is not possible, rigorously enforced rules, signs and signals dictating temporal segregation. Road users, according to the established paradigm, are irresponsible, stupid, selfish automatons whose safety can only be assured by physical barriers to conflict, supplemented by legal sanctions for disobeying the rules.

“Shared space” stands many of the traditional assumptions on their heads. It assumes a very different road user ‐ one who is responsible, alert and responsive to evidence of safety or danger. It proposes tearing down physical barriers such as pedestrian guard rails and segregation infrastructure such as pedestrian bridges, and filling in pedestrian tunnels. It also proposes removing stop signs and traffic lights and other signage and road markings demanding compliance at the cost of criminal or financial sanctions. It deliberately creates uncertainty as to who has the right of way on the assumption that road users will work it out for themselves in a civilized fashion.

Download “Where and when is shared space safe?” (PDF)

Jul
08
2011

Reducing zero risk

Judith Hackitt head of the UK Health and Safety Executive, has recently been complaining about “the creeping culture of risk-aversion and fear of litigation” and the “jobsworths” responsible for its promotion. The HSE appears to be losing the battle. Below I set out a piece that I was asked to write for my local tenants and residents news letter and website – http://thebrunswick.org/ .

 

Brunswick Tenants, Residents and Leaseholders

Many of you (I’m told 370) will have received a letter from City Restoration seeking an appointment to “carry out safety works to your windows.”

The windows in question are the vertical opening ones. Those commissioning the work believe that there is a risk that they might blow open in a high wind, shatter, and shower those beneath with shards of glass.

The proposed solution is to apply safety film to the insides of the windows in question. Flats above the Renoir-Gap – that has many people walking and eating below – have already received the treatment. My flat received this treatment before I bought it and I can vouch for the fact that it is invisible – I didn’t know I had it.

Camden now proposes to apply the same “safety works” to all the other flats in the Brunswick on the grounds that any opening window could blow open, shatter and shower people below with glass. It would appear to be a very small risk. Very few people can be seen walking below these windows – and even fewer in conditions of storm and high winds. No statistics are available for the number that have blown open and shattered. But when I inquired what sort of risk assessment had been done to justify these “safety works” I was told that the works were justified by the judgment that “IT COULD HAPPEN”.

I have been reassured by the Camden officer responsible that the cost of the works will not appear on our service charge bills; the cost will be recovered from the Camden Housing Repairs Budget – which means that, if the same zero risk strategy is being pursued throughout Camden, we will pay for it through our Council Tax.

For an extended version of this complaint please see my website at www.john-adams.co.uk .

 

The HSE provides some guidance

“HSE believes that an individual risk of death of one in a million per annum for both workers and the public corresponds to a very low level of risk and should be used as a guideline for the boundary between the broadly acceptable and tolerable regions.” (Reducing risks, protecting people http://www.hse.gov.uk/risk/theory/r2p2.htm).

It goes on “we live in an environment of appreciable risks of various kinds which contribute to a background level of risk – typically a risk of death of one in a hundred per year averaged over a lifetime. A residual risk of one in a million per year is extremely small when compared to this background level of risk. Indeed many activities which people are prepared to accept in their daily lives for the benefits they bring, for example, using gas and electricity, or engaging in air travel, entail or exceed such levels of residual risk.” Such risks, the HSE advises are “generally regarded as insignificant and adequately controlled.”

I looked up the numbers. The risk is already insignificant and adequately controlled. In England and Wales in the last year for which data are available 2 people died as a result of “contact with sharp glass” (Office of National Statistics, Mortality Statistics, Series DH2 no.32 Table 2.19). http://www.statistics.gov.uk/downloads/theme_health/Dh2_32/DH2_No32_2005.pdf

Spread over the population of England and Wales this represents an annual risk of 1 in 27 million, considerably less than the risk of being killed by lightening. But given the great variety of ways in which people might encounter sharp glass, in addition to being showered by a shattered window, it is highly probable that the actuarial risk of dying from the threat that Camden is now addressing is zero.

The fear of being found guilty of culpable negligence is one of the principal drivers of the creeping risk aversion denounced by Hackett. If something nasty could happen on your watch, and you might be held responsible, and you don’t have to pay for measures that reduce its likelihood, why take the chance, however minute the risk?

Those with an institutional responsibility for safety can always find one more thing that could happen. Their task is open ended. The above example of bureaucratic risk aversion is a small one of no great consequence – on its own. But it is endlessly repeated and wastes an enormous amount of money. Many things “could happen” – the precautionary principle allied to a vivid imagination can bankrupt any government.

Jun
27
2011

Road Safety: Myth Perpetuation

On 30 June and 1 July Oxford Brookes University is holding a History of Road Safety Symposium (http://ah.brookes.ac.uk/conference/history_of_road_safety_symposium). History, as they say, is written by the victors.

The concluding speaker is Rob Gifford, Executive Director of the Parliamentary Advisory Council for Transport Safety. The title of his presentation is “How parliament came to love seat belts.”

PACTS offers historians this view of its victory in securing Parliament’s love of seat belts, which culminated in the passage of the law (on its website at http://www.pacts.org.uk/newsletters.php?id=2).

“DfT Celebrates 25th Anniversary of the introduction of seatbelts

On the 31st January 2008, the 25th anniversary of the law change which made front seatbelt wearing compulsory was celebrated. PACTS itself was set up by Barry Sheerman MP as part of the fight to get mandatory seatbelt wearing turned into legislation. Eight years later it became compulsory for all backseat passengers to use seatbelts and it is estimated that since the introduction of the first law change in 1983, seatbelts have prevented 60,000 deaths and over 670,000 serious injuries.”

I have been challenging the PACTS view of seat belt history since before it was history – http://john-adams.co.uk/wp-content/uploads/2006/SAE%20seatbelts.pdf – but to no avail.

My interest was re-stimulated by the absurd claims made by PACTS in celebration of the 25th anniversary of its achievement. I have challenged the claim in a number of blogs about seat belts on my website – http://www.john-adams.co.uk/category/seat-belts/ – including four open letters to the Executive Director of PACTS.

A “History of Road Safety Symposium” is an excellent idea and the programme includes some excellent contributors. It is a great pity that it will be undermined by giving the final slot to a celebration – unopposed – of the discredited seat-belt law.

May
05
2011

Priorities

I’ve just had an email from the chair of the Bournemouth Cycling Forum with an interesting complaint. Local police are targeting “criminal” cyclists who cycle without lights and cycle on the pavement.
He questions whether, in these straitened times, these should be police priorities. Does anyone have any evidence that cycling without lights is dangerous? The last time I was in Amsterdam, a city with a vastly superior cycling safety record to anywhere in the UK, I conducted a scientific survey, for half an hour after dark, of passing cyclists – 50% had no lights.
On the subject of pavement cycling he has done his research. He has found guidelines from the Home Office on the 1999 fixed-penalty fines for pavement cycling. They explicitly state: “the issue is about inconsiderate cycling on the pavements. The new provisions are not aimed at responsible cyclists who sometimes feel obliged to use the pavement out of fear of the traffic, and who show consideration to other road users when doing so. Chief officers recognise that the fixed penalty needs to be used with a considerable degree of discretion and it cannot be issued to anyone under the age of 16. (Letter to Mr H. Peel from John Crozier of The Home Office, reference T5080/4, 23 February 2004)”
He (his name is name is Mike Chalkley – cycling@mikeandche.co.uk -) makes a further compelling point. “I personally believe cyclists should on the whole be treated as pedestrians are and allowed to do as they please (unless clearly endangering others through inconsiderate or dangerous behaviour). The traffic laws that apply to them are anachronistic and archaic and do nothing but fuel fear from both the Police and society as a whole.”
I agree with Mike. Comments welcomed.

May
05
2011

Bicycle Bomb Update

On 20 April 2011 I was invited to speak at a conference on “Critical Infrastructure Protection” at the Counter Terror Expo at the Olympia in London. The two vast Olympia exhibition halls were filled with exhibitors selling protection against terrorists: on display were lorry-bomb-resistant barriers and bollards, blast containment solutions, CCTV and covert surveillance systems, CBRN detection and protection, explosive detection systems, body armour, automatic number plate recognition hardware and software …… and much much more – click here for a full list of exhibitors. Counter-terrorism is, by all appearances, a vast and profitable industry, and one with an obvious incentive to stress the urgent need for its services. There were no exhibitors posing the question “Is all this necessary?”

In my presentation I argued for a sense of proportion – the precautionary principle allied to a vivid imagination can justify the denial of civil liberties and bankrupt any government. I cited the particular example of the police in London confiscating naked bicycles in the vicinity of Parliament Square and Whitehall on the grounds that they might be pipe bombs in disguise. I said that I could find no evidence of anyone, anywhere, ever having been killed by such a device – for previous postings on this subject click here.

This provoked a challenge on a website called Coldstreamers – a chat room for current and former members of the Coldstream Guards. It is refreshing to encounter people on the security frontline who are prepared discuss this issue. London’s Metropolitan Police have been conspicuously unwilling to provide a justification for their cycle parking ban in Westminster.

Someone who had been at my presentation said “I was at the counter terrorism expo last week and one of the professors said no one ever in the world had been killed by a bomb disguised as a bike and I’m sure he is wrong. Can any one help?”

Such help was not forthcoming. After about 400 hits one respondent familiar with the evidence said “Has it [a pipe bomb disguised as a bicycle] actually killed anyone? I think not.” And another denounced the police reaction as “a totally paranoid act.” After a further week and more than another 100 views without further comment this appears to be the final Coldstreamers’ word on the subject.

One definition of paranoia is “an excessive suspicion of the motives of others”. Judged by the actuarial evidence – no evidence has so far been produced of anyone in the world having been killed by a pipe bomb disguised as a bicycle – the police reaction is paranoid. The reaction is also arbitrary. It is possible, if difficult, to disguise a pipe bomb as a bicycle. But there are many other easier ways, from backpacks and briefcases to cars and lorries, to create a much larger explosion. If bicycles are to be banned from Parliament Square and Whitehall why not all the other places in London where large numbers of people congregate? The paranoid fear of bicycles carried to its logical conclusion would eliminate bicycles as a mode of transport.

Proving a negative is always difficult. The quest for evidence that a pipe bomb disguised as a bicycle has ever harmed anyone continues. But whether, in the whole history of terrorism, bicycle-pipe bombs have killed one person, or two, or a few, or no one, it still seems fair to characterize banning the parking of naked bicycles in Westminster as arbitrary and paranoid.

Feb
08
2011

Two methods of transport-safety myth building

1. Simple assertion.

An example can be found in the current issue of The Economist by the journal’s Science and Technology correspondent writing under the name of Babbage (http://www.economist.com/blogs/babbage/2011/02/road_safety).  Babbage notes that the US fatality rate has been “inching down over the past half century” and then proceeds to explain why: it is the result of “the wholesale introduction of safety belts and air-bags, as well as tougher drunk-driving laws.”  This provoked me into posting the following comment on Babbage’s article.

“Babbage disappoints. He notes that in the US the fatality rate per 100m vehicle-miles had “been steadily inching down over the past half century.” He goes on “For that, traffic authorities everywhere can thank the wholesale introduction of safety-belts and air-bags, as well as tougher drunk-driving laws.”

The “inching down” has been going on for much longer than the last half century – it began with the Model-T – and long pre-dates seat belts, air bags and drunk-driving laws. In Britain the “inching” rate has been about 5% a year since 1950 and the death rate per 100m vehicle kilometers is now about one twentieth of the 1950 level. The contribution of seat belt and drunk driving laws to this “inching” is statistically undetectable – see “Managing Transport Risks: what works?” (http://john-adams.co.uk/2010/12/02/managing-transport-risks-what-works/).

The inching-down with increasing levels of motorization, noted by Babbage, is a social learning process first described by Reuben Smeed in 1949. It is manifest in countries at all levels of motorization and appears to have little connection with technical or legal safety interventions. Today countries with low levels of car ownership are achieving kill rates per vehicle, with modern imported cars with 100 years of safety technology built into them, as high or higher than were achieved with model-Ts 100 years ago. The inching-own process is now widely labeled, in honour of its discoverer, as the manifestation of Smeed’s Law – try Google.”

2. Suppression of evidence.

Culling files recently in the course of moving house I came across some correspondence with the World Health Organization. In 1986 they had commissioned an article by me on seat belt legislation for The International Digest of Health Legislation. I assumed that the invitation was the result of things that I had already published on the subject:

http://john-adams.co.uk/wp-content/uploads/2006/SAE%20seatbelts.pdf
http://john-adams.co.uk/wp-content/uploads/2008/10/significance.pdf
http://john-adams.co.uk/wp-content/uploads/2007/10/risk%20and%20freedom.pdf, chapter 5.

The article I submitted summarized the evidence and arguments of these earlier essays. I assumed they knew what they were commissioning.

I received a prompt reply from someone with the title “Chief, Health Legislation”:  “I would like to inform you that, for editorial reasons, your review will not appear in the International Digest of Health Legislation. Even though, under the terms of the contractual agreement with you, copyright in the text is vested with the Organization, we have no objection to the review being submitted by you for publication elsewhere, subject to the proviso that no mention is made of the fact that the review was commissioned and an honorarium was paid by WHO.

From that day to this (http://www.who.int/roadsafety/projects/manuals/seatbelt/en/) the WHO has campaigned for seat-belt legislation. No mention should be made of evidence that casts doubt on the efficacy of such legislation – that would undermine the efficacy of its campaign for more legislation.

Dec
02
2010

Managing transport risks: what works?

I have been invited to contribute a chapter to a book called Risk Theory Handbook to be published by Springer. Publication is scheduled for a year from now, so there is still time to make changes/corrections/improvements. Comments are welcomed. Here is the abstract.

Abstract

What does a transport safety regulator have in common with a shaman conducting a rain dance? They both have an inflated opinion of the effectiveness of their interventions in the functioning of the complex interactive systems they purport to influence or control. There is however a significant difference. The clouds are indifferent to the antics of the shaman and his followers. But people react to the edicts of a regulator and frequently not in the way the regulator intends. There are two different kinds of manager involved in the management of transport risks: there are the “official”, institutional, risk managers who strive incessantly to make the systems for which they are responsible safer, and there are the billions of individual fallible human users of the systems, each balancing the rewards of risk against the potential accident risks associated with their behaviour. Conventional road safety measures rest on a model of human behavior that assumes that road users are stupid, obedient automatons who are unresponsive to perceived changes in risk and who need protecting, by law, from their own and others’ stupidity. The idea of risk compensation underpins an alternative model of human behavior: that road users are intelligent, vigilant, responsive to evidence of safety and danger and, given the right signals and incentives, considerate.

The full paper can be found here.

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