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have you ever heard of the Happy Endings Foundation? Well neither had I until Sunday morning when I saw on the BBC news an article about their campaign to ban books with sad endings for children.

The BBC paid for two experts - a child psychologist and someone else - to come into the studio and pontificate on how this campagn was misguided. What a pity though that these experts, and the BBC news researchers (and the Daily Mail, who were also taken in) were not so expert in the realm of critical thinking.

The first clues that all was not well could be found in the web site itself. Rewrite Lemony Snicket? Are you allowed to do that? Why would you want to? Also the BBC admitted they could not actually contact anyone from this web site to come on to their programme.

Also, what an odd list of books they were saying had happy endings.

But one skill that should be taught to school children up and down the country when we teach them basic IT skills is how to find out who pubilshed a web page. This is not actually very hard. Point your web browser at any of the whois services, but I particularly like this one:

http://www.whois.sc/

Look down the page for the registrant details. In this case we have a registrant as follows:

Registrant Name:Peter Rope Registrant Organization:ArtScience

Usually this is enough (and it is here, if you know who ArtScience are - a promotional company trying to promote Lemony Snicket!) but this whois search has a great feature. It will do a reverse domain lookup to find out what other web sites are hosted on the same web server as this one. In this case we find:

Artscience.net Artscienceclick.com Charlie-bone.com

And a quick click on any of these links will quickly show you that these people are in the business of marketing children’s books.

The BBC was duped by marketeers. I hope an apology will follow for using license payers money to advertise someone’s books.

The Daily Mail was also duped - but that is par for the course.

But the BBC really should know better.

The media is working itself up into a feeding frenzy again. This week’s issue: the alleged dangers of WiFi radiation. First BBC Radio news, then Newsnight, now the Daily Telegraph have all had articles from quoting from people who believe that there might be health risks from WiFi. The BBC programmes at least balanced the sillier claims by noting that WiFi power output is far lower than that from mobile phones.

The Daily Telegraph, on the other hand, had this nonsense:

However it is believed that a classroom containing 20 laptops and two routers could combine and be equivalent to the emission from a mobile phone.

Notice the use of passive voice: “it is believed”. Who believes this?

It turns out that no-one does, although the Telegraph quotes from the “Powerwatch” web site. On this site, there is a calculation designed to show that a room full of 20 computers and an access point (or two) is approaching the power output of a mobile phone call.

But this is arrant nonsense. It is nonsense because of the silly assumptions being made about average distance from antennae. It is nonsense because they first make an assumption of low power output from the phone, and it is especially nonsense because it makes no difference whether you have one computer or fifty in a room. The maximum power output is the same - capped in the UK at 100mw (but usually less than this).

Let me explain: WiFi stations are receiving a radio signal when they receive data. But if two stations transmit a signal at the same time then what occurs is a collision - the signal is garbled and not received. The solution is that WiFi uses a collision avoidance scheme to try to ensure that packets are never sent out whilst another station is already transmitting. A couple of carrier sense mechanisms are used to do this, and the result is a very low collision rate. Essentially, if one station is talking, all the other stations are quiet. Click on the thumbnail image to see how this looks in practice. Each wireless station waits a random amount of time before transmitting, and if another station transmits first, the wireless station will quietly defer to it.

Therefore the maximum power output from a room of 20 computers remains capped at 100mw. What is more, no one station is transmitting all the time. For the majority of the time, even on a congested network, each station is actually transmitting nothing.

And that brings us to the next bit of nonsense - the assumption of the amount of traffic in transit. The powerwatch page assumes more than 100% usage for periods of two hours or more in its calculations. Note that if a single wireless station on an IEEE 802.11g network were downloading constantly (and that the downstream network could maintain the same throughput), then even assuming protocol overheads reduce the actual throughput to a mere 30 Mbps, over a course of two hours, that station would download some 26 Gigabytes of data.

To put this in perspective, fairly heavy Internet users download about this quantity of data in a month. Light users (people just browsing the web, using email and similar) would not get close to this figure.

26 Gigabytes is the equivalent of about 44 CD images, or several thousand podcasts. It is a guge quantity of data - not the kind of thing people will be downloading in one sitting - and certainly not regularly.

Ah, you say - but spread between 20 computers? What classroom environment is encouraging pupils to download over a gigabyte of data per computer? None!

So the assumption of 100% utilisation is nonsense.

Next problem: The assumption is made that people are - on average - a metre from the transmitting antenna.

This is just silly. The writers seem to know that magnetic fields decrease by the square of the distance from the antenna, but they assume that on average, people are a metre from the emitted radiation. Based on the fact this is a classroom, and 20 stations are variously transmitting, the fact that some of these transmitters will be many metres away only really makes this assumption if the pupils have swallowed the transmitter.

Admittedly, I wouldn’t put this past some children - but if they have done so, they probably have worse problems to deal with than the emitted signal from the station!

No, in fact the vast majority of the transmissions come from the access point. (Remember, we download much morethan we upload) this may not even be in the class, but if it is, it will probably be several metres from even the nearest child. The law of squares tells us that these signals will be far lower than the silly assumption made on the powerwatch page and repeated uncritically by the Daily Telegraph.

As one commentator on the Telegraph page says:

“Can there ever be a better example of why the current decline of Physics teaching in schools and universities is so worrying?”

Let’s give the last word to Mike Clark, senior spokesperson for the Health Protection Agency. He has run the figures rather more intelligently than the Powerwatch pressure group, and tells us that 1 year of exposure to WiFi radiation in a classroom is equivalent to 20 minutes on a mobile phone.

Maybe we could quibble and bring that down to a month or so. So what? The worry with mobile phones is that the radiation causes excitation of water molecules in the brain near where the phone is held to the head. This causes a slight warming effect which could theoretically be a cause for concern, although there is no proof of harmful effects.

WiFi radiation - if it causes any warming at all - is so slight as to be unmeasurable.

There is no risk here.

When Mr Spock says something is logical in Star Trek, what he often seems to mean is that something is common sense in som ultilitarian way of thinking. Thus “The needs of the many outweigh the needs of the few” is a clear utilitarian statement.

What he does not do is couch everything he says in terms of formal logic. And there is one very good reason why that may be a good thing! There is a principle in logic known as “ex falso sequitur quodlibet” - from a contradiction, everything follows. What this principle tells us is that if there is a single inconsistency of the form “P is both true and false” (a negation inconsistency), then every other proposition can be validly implied. If such a contradiction is allowed, then essentially everything is true.

Here is the proof:

1. P and P’ (that is, P is both true and false)

2. P (therefore P is true)

3. P or Q (Either P is true or Q is true)

4. P’ (P is false from 1. above)

5. Q (from 3. If P is false, Q is true).

But that is nonsense, you say - because perhaps Q has nothing to do with P. Hold that thought, because the other problem is what propositions are actually both true and false?

Well let us suppose that I am standing in the doorway of a room. One foot is in the room, and one foot is out. Am I in the room or not? You could argue that it is both true and false that I am in the room. Let us apply the proposition to the proof above:

1. I am in the room AND I am not in the room

2. I am in the room

3. It is therefore true that either I am in the room or black is white.

4. But I am not in the room

5. Therefore, from 3 and 4 I can see that black is white.

(And, as Douglas Adams pointed out, I shall now go and get myself killed on a zebra crossing).

But the point here is not that we can really prove anything, but that we don’t instinctively think logically. We allow that some things can be kind of true and kind of false, and we don’t actuall accept step 3 in the above argument. If a proposition has nothing to do with another, then why should its negation inconsistency imply the truth (and simultanously the falsehood) of the other proposition?

Human brains are wired up to be “paraconsistent”. Paraconsistency is a type of logic that ignores or removes the ex falso proof, often by insisting on the relevance of conjoined propositions. Whether we strictly need paraconsistent logic is a whole larger debate, but we need to bear in mind that our own thinking is more relevance based than strictly logical. And that is, perhaps, a good thing.

There are a number of sites around which retell a piece of naval history. For instance this one on myspace:

It was necessary to keep a good supply of cannonballs near the cannon on war ships. But how to prevent them from rolling about the deck was the problem. The best storage method devised was to stack them as a square based pyramid, with one ball on top, resting on four, resting on nine, which rested on sixteen. Thus, a supply of 30 cannon balls could be stacked in a small area right next to the cannon.

There was only one problem — how to prevent the bottom layer from sliding/rolling from under the others. The solution was a metal plate with 16 round indentations, called a Monkey. But if this plate was made of iron, the iron balls would quickly rust to it.

The solution to the rusting problem was to make Brass Monkeys. Few landlubbers realize that brass contracts much more and much faster than iron when chilled. Consequently, when the temperature dropped too far, the brass indentations would shrink so much that the iron cannon balls would come right off the monkey.

Thus, it was quite literally, cold enough to freeze the balls off a brass monkey. And all this time, you thought that was a vulgar expression, didn’t you?

Similar stories can be found at Life with Larry and The Gray Monk. The latter even purports to have a picture of one of these.

The problem is, no such ships fittings ever existed.

The point I want to make is that we cannot always rely on the popular explanations, just because someone we deem to be an authority has proffered the information, and when we hold something to be true, it is often necessary to undergo rather more research than to simply ask a historian friend (or local pastor, or church website or whatever), to verify that this thing is actually true.

You see, this explanation is wrong on several points:

1. Stacks of cannon balls were held in garlands, not monkeys

2. These stacks were made from wood, attached to the edge of the ship. The balls were not piled in stacks, but each seated in the garland in such a way that they would not come loose when the ship was pitching and yawing at sea.

3. The thermal coefficient of expansion is such that, taking some reasonable values for the size of the brass plate and the size of the cannon balls, and allowing that they would not be stacked so precariously that they would fall at the slightest touch, let alone the movement of a ship’s deck, it has been calculated that the temperature would need to dip to minus several thousand degrees celsius to cause the stack to collapse (and we don’t really need to consider anything past absolute zero, obviously). A few degrees Celsius would not have a noticeable effect on the stack - it may not even be measurable.

4. There are no sources that verify the story. It seems to be a recent invention.

Another, slightly more plausible story is that the phrase referred to freezing a ball on a brass monkey. In this version, brass monkeys are lifting gear on ships used to raise cannon balls to the gun deck in the place of powder monkeys (small and agile boys who would fetch the gunpowder from the ship’s magazine in times of battle). The argument then is that the lifting gear (made from brass, so it did not rust) would get covered in saline sea water. In times of extreme cold, the water would freeze. A cannon ball would then be placed on the lifting gear, and because of its weight, the pressure would briefly melt the ice - but being so cold, the ice would re-melt by the time the ball was lifted to the gun deck. Thus the weather was cold enough to freeze the ball onto the brass monkey.

Sounds better, but it is also implausible, because:

1. I cannot find any clear evidence that such lifting equipment existed and was called a brass monkey.

2. Lifting gear for ships certainly did (and does exist), but why for cannonballs? Powder monkeys fetched gun powder from the magazine, hidden deep in the ships hull, behind a dampenned “fearnought screen”, because the worst thing that could happen in a sea battle would be to get so much as a spark in the magazine. Thus powder monkeys fetched powder on a just in time basis for safety. Cannon balls, on the other hand, were kept near the guns. Being large lumps of iron, there was no danger these would explode! Thus no lifting equipment required.

3. There are no sources that back up this explanation either.

The only source I have ever found was a secondary source that suggested a monkey was a type of cannon. [The concise OED cites “Art, Rendition Edinburgh Castle”, published 1650 which refers to “28 short brass munkeys, alias dogs”. This would put the term in the civil war, but the cannon, and not the ball or the stack is meant. I don’t have any access to the original source material].

Thus all I am really certain of, regarding this phrase, is my ignorance.

But that is the point: We often believe things on trust. These blog writers have trusted some information they have been given about this term. I likewise have believed a similar explanation in the past.

But there comes a time, when a subject is important enough to us, that we must move forwards - verify what we know, and treat critically that which we believe.

And this is true in all walks of life. For instance, in our churches, we can go so far by listening to the teachings of our church leaders, but how do we know that the teaching is true? How do we know that a certain doctrine is held by us to be correct, because it really is true, rather than simply because we have been told it is true? (Yes, we can look at scripture - but my point is : how do we know that the interpretation we have accepted of that scripture is true)

Often we need to look past what we are told by people we trust, and actually evaluate information as well as we are able from the primary sources, or (if that is impossible) from secondary sources who do not have a bias towards our own viewpoint.

Now this last matter is crucial, for if I read the works of a certain respected preacher (Billy Graham perhaps), and I say, “yes, he is quite correct on the need for evangelism” and such like, but then “he is in error on the Holy Spirit”, then all I am saying is that I like Billy Graham’s ideas when they agree with mine.

But if I read all he says on the Holy Spirit, and say “is his view consistent?” then I am setting prejudgement aside, and exploring the issue for myself.

We can do this with Brass Monkey’s, and we can do it with Christian Doctrine. We can do it with current affairs and politics too.

When we do it well, I think we move closer to an appreciation of truth.

When discussing issues around abortion, one often sees an argument such as this from the pro-choice side:

when all is said and done, the question most prevalent should be: “Do we want our orphanages and adoption agencies overflowing with uncared for children?”

The argument being made is that we should allow people to kill foetal life, because the consequence of not doing so would be children who are uncared for, and that this is such a miserable outcome that the alternative is somehow better than the consequence.

But our pity for uncared-for children is being hhijacked here. If we can convince ourselves that killing life before it reaches some point of development that we consider crucial is better than allowing children to live in misery then is it not better to kill them?

But in that case, if a child is born to a mother who we suspect will be abusive or will abandon the child, should we not then kill the new born child? Why would one course of action be better than the other?

If you ask a pro-choice advocate this question, they will give you answers based on issues such as the mother’s right to choose what she does with her body and so on.

And that is fine. We can then evaluate those arguments on their own merits, but note that these issues are the real nub of the argument. The issue is an issue of morality. People must weigh up the morality of killing human life with the morality of restraining a mother’s choice.

But an appeal to pity (argumentum ad misericordiam to give it its latin name), is fallacious. It is not the argument that needs to be answered, and it distracts us from the real issue at hand.

Over on the MInTheGap blog, there is a post which links to this article about how global warming is nothing to worry about.

I wrote a couple of replies on the MInTheGap blog which you can take a look at, but to summarise, I noted that the article was largely an appeal to authority. The writer - one Timothy F Ball - claims:

I was one of the first Canadian Ph.Ds. in Climatology and I have an extensive background in climatology, especially the reconstruction of past climates and the impact of climate change on human history and the human condition

I am not sure what evidence he has for being one of the first doctors in Climatology in Canada. I suspect there may be some hair splitting going on there, as there were many Canadians prior to this who researched climate.

As to his extensive background in climatology, I cannot find much evidence for this - but he is right to draw attention to the fact that reconstruction of past climates is his area of expertise. His thesis from the University of London was:

“Climate Change in Central Canada, A Preliminary Analysis of Weather Information from the Hudson’s Bay Company Forts at York Factory and Churchill Factory, 1714-1850.”

I couldn’t immediately find any published papers by him on climate, so a web search revealed these titles that someone else turned up after an exhaustive search of web of science and worldcat:

1. “Historical Evidence and Climatic Implications of a Shift in the Boreal Forest Tundra Transition in Central Canada” Climatic Change 1986

2. “Instrumental Temperature Records at two Sites in Central Canada, 1768 TO 1910″ Climatic Change 1984

3. “The migration of Geese as an indicator of climate change in the southern Hudson-Bay region between 1715 and 1851,” Climatic Change 5, 85-93 (1983).

4. “Climate of 2 locations of the southwestern corner of Hudson-Bay -AD 1720-1729.” International Journal of Climatology 14, 1151-1168 (1994).

So Dr Ball’s expertise lie in understanding how Canadian climate has changed between the eighteenth and nineteenth centuries. This, of course, ties in with the little ice age which followed the medieval warm period, and is an interesting period because of the anomalous conditions in Europe (and the Hudson Bay area) at this time. But in his piece quoted above, Ball gives the impression that the little ice age was a world wide phenomenon. he wrote:

The world has warmed since 1680, the nadir of a cool period called the Little Ice Age (LIA)

Notice that all Dr Ball’s research is over 12 years old. Increasingly we have come to understand that the little ice age was a localised phenomenon. Some have suggested this was because of melt water from retreat of the Greenland ice sheet in the medieval warm period causing a failure of the North atlantic drift to warm Europe (because the melt water had lower salinity, causing the cold water to sink and drive the North Atlantic drift down).

Whatever the reason though, recent research is clear that the little ice age was not a global phenomenon, but a localised one. See for instance:

“Climate Change 2001: Working Group I: The Scientific Basis 2.3.3 Was there a “Little Ice Age” and a “Medieval Warm Period”?”. Intergovernmental Panel on Climate Change. (2002)

Now this is the sum of Dr Ball’s research. Despite his great claims to be a leading climatologist, he has published just 4 peer reviewed papers on the subject - all on Canadian climate change prior to the industrial period.

To put that in context, a researcher in the UK who does not produce at least four peer reviewed papers over three years would not be even entered in the research assessment exercise as a current researcher.

He disagrees with a global consensus on climate change, but he does not carry out research on the subject. He has not published any research on the subject for well over a decade. We would do well not to be taken in by such people.

A straw man argument is an argument where someone characterises the position of another as being something slightly different (and weaker) than the actual position of the other person. Such arguments are often deceptive, making it look as if someone has proven their case - when in fact all they have done is demolish the straw man - the weaker argument that is not actually held by anyone!

An example. Richard Dawkins says:

“Faith means blind trust, in the absence of evidence, even in the teeth of evidence.”

He then takes issue with this faith for not being based on evidence. To many his argument seems convincing, but Christians do not believe his definition. A A Hodge wrote:

“Faith must have adequate evidence, else it is mere superstition.”

And that is the faith of Christians everywhere. There is no blind trust. Christian faith is based on evidence, experience and the knowledge of God. Thus Dawkins demolishes a straw man.

In previous posts I have been reposting some correspondence I had with someone over issues of speeding. As we saw in the previous posts, the writer (MW) was relying on anecdotal evidence, rather than hard data to inform his views. For completeness, I recount below the remainder of my reply to MW, which dealt with speeding policy, sloganeering, some suggested solutions from me, and a bit about logic (MW claimed his logic was clear and sequential, which is why he numbered his propositions).

MW continued:

4) Current thinking by the government is that lower speeds would reduce RTA mortality - why do you think they are conducting such extensive campaigns to get people to slow down, illustrating their argument with just this point?

My reply:

The government want to be seen to be doing something. They also do not hold a consensus on “current thinking”. Indeed I note that current thinking is very much divided on the role of speed limitation on reducing mortality from road traffic accidents. There have clearly been benefits in some locales from reducing speeds, but taken beyond what is sensible, the results have been quite the opposite.

In 1995, Suffolk introduced 450 30mph limits on roads that were previously 60mph, since then the number of accidents has risen by an average of 51 per year, after falling by an average of 171 per year for the preceding seven years.

You can see the statistics and the whole story at:

http://www.abd.org.uk/suffolkaccidenttrends.htm

So no, there is no consensus of current thinking “that lower speeds would reduce RTA mortality”. You are wrong on this too.

5) The current laws are not adequate to deal with the general attitude so clearly exemplified by some of the member of this group; that it is okay to speed because you’re such good drivers.

That argument is ad hominem. As far as I am aware, no such argument has been proposed.

There is nothing wrong with ad hominem argument, except in the rarefied world of Tractatus groupies. Most of political philosophy is ad hominem, just look at Hobbes, Locke, Marx et al, they reason through preference.

This is an irrelevant appeal to authority. It is as fallacious as the ad hominem. It is also wrong. I have not read much Marx, but Hobbes and Locke I have read and not noticed a strong tendency to ad hominem arguments from either. There are certain assumptions in their work, but that is something different. Locke sees property as something special, and the non-propertied man somehow less than human (not his term of course). That is a pragmatic assumption to make his philosophy work, and Locke is - of course - one of the greatest philosophical pragmatists. However that does not make his argument ad hominem unless he dismisses the logic of another based on their lack of property (which to my knowledge he does not).

Now ad hominem arguments are fallacious, and if you do not agree with me then all I can say is that your arguments are of no consequence to me because your surname is Winters, and [anecdotally] everyone I ever met with that surname was a simpleton! (:o)

And finally to your assertion that people who have disagreed with you over speed humps and speed limiters think it is okay to speed: I think no such thing. I have never said it is okay to speed and I don’t think it is. I have never in my life had a speeding ticket, nor a single point on my license, and I am a paid up member of the IAM. I agree with their policy that speed limits are limits. I also have never had an accident.

But of course it is so much easier to cast aspersions at others rather than deal with the issues. That is why the ad hominem argument is so popular - because it is so much easier than actually thinking about the issues under discussion.

6) Such culturally embedded attitudes require sterner measures to counter

You have not demonstrated a culturally embedded attitude. I also don’t think that the law is the instrument of change for cultural attitudes - it is education that is needed, which needs to treat people as though they have the wherewithal to comprehend an issue beyond simplistic sloganeering.

In truth, we are approaching this from two differing philosophical standpoints. You seek empirical truth and logical reasoning. I’m offering deductive processes based upon witness testimony. A Posteriori if you like, given your fondness for archaic expressions.

Statistical data such as I have presented here is a posteriori. It is based upon observation and is not deduced a priori. We may note that scientists and statisticians are empiricists almost to a man. Thus it is a posteriori propositions that are garnered to make sense of the world, and a priori propositions are secondary, being analytic.

So no, our differences here do not come from some epistemological distinction between rationalists and empiricists. The problem here is that you are not thinking critically at all.

7) If you are prevented from speeding then the problem is partially solved

No, the problem is merely shifted. Treat the cause, not the symptoms.

What were you saying about simplistic sloganeering? This is one of the best. Treat the cause, not the symptoms. Apply your logic to that. Where do you find cause?

In excessive use of the motor car, which leads to dependence on the same, which makes it politically unacceptable to demand that motor vehicle use might be limited to those who can consistently prove themselves competent and safe to move said vehicles around.

We combat this by several measures:

1. Break dependence on motor vehicles by funding public transport, changing planning laws to enable better designed communities with amenities that do not require road trips, encourage alternative transport means, discourage cars where they are problematic through road tolls and orders etc.

2. Radically increase driver education, both for existing drivers and for new drivers. Consider some level of testing that at least gets drivers looking at the Highway Code! (How many drivers even know where their copy is?!) A full driving retest at regular intervals would be good but impractical all at once, so instead use driving schools for those who commit traffic offences, and demand retesting for anyone who loses their license. Life bans for driving should also be issued where drivers are unwilling to improve their driving competence and attitudes.

I could go on, but you get the idea, I am sure.

One of the problems with using semantically accurate deduction is the lack of any human quality. I know motorists, in general, drive too fast, because I have seen them. You would argue that because I have only seen black swans my logic is faulty in assuming that all swans are black.

I rather suspect you have only seen white swans, unless you live in Perth, Western Australia.

If, based on your empirical observation that all swans you have seen are white you then proceed to deduce that all swans are white, then yes - your logic is faulty of course. However you may indeed induce the hypothesis that all swans are white, which is an essential part of the scientific method. I have no problem with that, but neither is it relevant here. On discovery of the Black Swan River, you must abandon your hypothesis and the faulty proposition. Likewise in the face of the evidence I have quoted above, I invite you to abandon your faulty hypotheses in the message you wrote previously.

You don’t appear to understand that in some cases, deduction from observation is perfectly valid,

You are referring to induction. A hypothesis is an induction and its validity is open to test. This is different from logical deduction and the absolute validity or otherwise of a logical argument.

Is there a better way to prevent speeding than to make the road unsuitable for fast driving?

Yes:

1. Better enforcement by the police. Use of Gatsos at accident blackspots etc. and use of police traffic cars to keep a check on driving standards.

2. Increase speed limits where they are clearly unsuitable, and then rigorously enforce those limits (e.g. raise the motorway limit to 80). This would be done alongside lowering limits in other areas.

3. More use of variable limits.

4. More rigorous road testing, including greater use of retesting and training following traffic offences.

5. Greater education perhaps through positive encouragements to undertake advanced driving courses.

6. A more well rounded debate in the media rather than repeated sloganeering

This is the voice of someone who does not understand marketing. At the risk of sounding patronising, you would only appeal to those of your intellectual standing and to be frank, you ain’t the problem.

Sloganeering panders to the myth that one is safe if, for instance, one is not speeding. That is quite untrue and an example of why such sloganeering is often counter productive. You will notice figures suggest that such marketing campaigns have spectacularly failed to change attitudes.

I have been detailing a reply to a correspondent, MW, about speeding. He argued (against the evidence) that most people break the speed limits, and that those who do not break speed limits tend not to have accidents. On investigation, both claims were clearly false - but MW preferred anecdote and prejudice to colour his views. I am reposting MWs message now, to show how easily we can make errors in our decisions if we base those decisions on anecdote and hunches.

In thi sthird article, we look at another of MWs claims - this time based on second hand reporting and our tendency to misremember what surveys are saying to bolster our world views.

MW wrote:

3) The UK has the highest child mortality rate attributable to RTAs in Europe. […] I heard it on the Beeb, in a discussion with one of the many Transport Ministers. I can’t be bothered to dig up a better source than that.

It was a pity that MW posted this without bothering to look it up, as he would have spared himself some embarrassement had he done so. MW is not alone in misremembering media reports. Frankly, I do so nearly every time - and I frequently find that when I go back and read the reports again, that I have the details wrong.

But MW could not be bothered to look up his sources, so I had to tell him he was wrong.

The UK road death rate is, of course, one of the lowest (I think probably the lowest - but I do not have latest figures in front of me. It was the lowest when I replied to MW) in Europe per head of population. We are about three or four times less likely to die in our cars than the French (or Americans for that matter), but our figures show that we have a poor record on pedestrian death, and particularly child pedestrian death.

We are not the worst in Europe. According to Department of Transport Figures I see that the UK child pedestrian death rate was .9 per 100,000 population. Which compares unfavourably with Austria, Denmark, Finland, Italy (.5); Netherlands, Germany (.6) and especially Sweden (.2). However we are streets ahead of Portugal (2.8), and significantly lower than Ireland (1.2), Luxembourg (1.3), and Spain (1.0). I also note that the comparison is only with Western Europe - although I expect that Eastern Europe might have lower figures, as there are generally fewer cars there.

So again your facts are wrong. Our child pedestrian death rate is poor, but not the worst in Europe. It is however a significant blot on our otherwise very good driving record.

We do, however, have a lower overall mortality rate than most of the rest of Europe, so I have discovered, which is food for thought.

We also might note that children living in the most socially deprived areas of the UK are up to three times as likely to be hit by a car than those living in the most affluent parts of the country. [”Streets Ahead”, Institute for Public Policy Research (IPPR) and the Imperial College Centre for Transport Studies (ICCTS)]

There are no doubt many factors for this, but it would perhaps be just as productive in reducing the child death toll to lift such children out of this social deprivation. This would also have long term benefits for the children and society as a whole… but it would cost more and take longer to implement than a speed hump and yet another speed limit, wouldn’t it.

In a previous article I wrote about a correspondent, MW, who argued (against the evidence) that most people break the speed limits - relying on anecdotal evidence.

He also wrote:

2) People who don’t break speed limits tend not have accidents

My answer:

Are you sure? I am sure I read an article somewhere that showed that people who tend to drive well below the speed limit are much more likely to have accidents than people who travel at around the speed limit (whether a little below or a little above). This was, I think, in an old issue of Advanced Driving magazine, although unfortunately I have no reference to hand.

Munden (1967), reported some interesting results for drivers in the United Kingdom who habitually drive at deviant speeds (speeds well above or below the average speed for a road.) The speed of selected drivers were observed and compared to the four preceding and four following vehicles. For drivers observed more than once, those traveling more than 1.8 standard deviations above or below the mean traffic speed had significantly higher crash rates. This from:

J. M. Munden, “The Relation Between A Driver’s Speed and His Accident Rate,” Report LR 88, Transport and Road Research Laboratory, Crowthorne, England, 1967.

But that survey was one of a number that discovered an interesting U shaped curve in accident rates against deviation from the mean speed by drivers (when excluding changes of speed for purposes of maneuvering). What is shown quite clearly is that both very slow moving vehicles and very fast moving vehicles are much more likely to have accidents. Strangely we do not see a move towards a simplistic “slowness kills” message, because we understand that other factors are at play here.

What is very interesting was some follow up research [2] by David L. Harkey, H. Douglas Robertson, and Scott E. Davis. “Assessment of Current Speed Zoning Criteria.” Transportation Research Record, 1281 (1990), p. 51.

“Speed at which accident risk is minimized occurred at the 90th percentile of the travel speeds observed.”

Thus those who exceed the speed limit a little are statistically (in that survey) the least likely to have accidents, and in fact all the U curves in all the studies show accident rates at their lowest at about 10% over the mean speed, which is usually a little over the speed limit.

Of course there are other surveys that show those who seek compliance with speeding laws are at less risk of having accidents, and that there is often a direct correlation between excessive speed in a driving situation and higher accident rates. I do not want to excuse habitual or excessive speeding, nor suggest that speeding is really acceptable. What these data do demonstrate, however, is that MW was wrong to say:

“People who don’t break speed limits tend not have accidents.”

Again the evidence shows otherwise. The statement is too simplistic and ignores the real data.

What we can say is that those who habitually and/or excessively speed are statistically more likely to have accidents.

Notes:

[1] The Relation Between a Driver’s Speed and His Accident Rate, Report LR 88 JM Munden - Road Research Laboratory, Crowthorne, England, 1967

[2] Assessment of Current Speed Zoning Criteria DL Harkey, HD Robertson, SE Davis - Transportation Research Record, 1990