Y Safle

Caredig i Natur wrote an article (in almost illegible yellow text on a bright green background – yuck) titled “Whingy Car Lovers” in which they made this wonderful observation:

Update, Thursday 7th January 2010: Today at 8.45 AM there were only two vehicles in Llanbadarn on Primrose Hill, where there would normally be a hundred blocking the road. Also today the local schools were closed as a precaution due to ‘snow’, even though in reality it isn’t bad at all. This shows how much of the local traffic is school-run based, and therefore a bypass would do nothing to reduce traffic in Llanbadarn Fawr. More roads won’t fix a car-addicted culture, they just encourage it.

So based on this so scientific analysis, they have assumed that nearly all traffic in Llanbadarn Fawr is caused by the school run.

Except look at the date they chose. 7 January 2010. The Daily Telegraph headline for that day was “Britain’s Freezing Weather: Worst Snow for 50 Years Paralyses Transport Networks”.

Aberystwyth is close to the sea and sheltered by hills from north-easterly winds that bring snow. Consequently on 7 January the snow in Aberystwyth and Llanbadarn was not as bad as the rest of the country. The whole of the rest of the country though was white! Even Aberystwyth and Llanbadarn were frozen and had some snow.

Now Caredig i Natur’s point is that the empty roads indicate that no Llanbadarn bypass is called for because most of the traffic is school traffic and not through traffic. He conveniently forgets to mention that there was no through traffic at all on that day because all the roads in and out of town were blocked by snow!

It wasn’t just the schools that were shut (because the teachers, support staff and many children could not get in). Everything was shut. Offices that were open were all but empty, and staff had walked in where they had got in at all. I myself could not move my car for the whole of that week despite living in Aberystwyth itself.

Such terrible sloppy misrepresentation of the facts does no one any good. Caredig i Nature? Angharedig i’r gwirionedd. (Kind to nature? Unkind to the truth).

the writer of the Caredig i Natur blog really really does not like cars taking children to school. To be fair he is not alone. Many people, including most of the parents in the cars, are not happy with the necessity of a daily school run. However, the blog writer is rather disingenuous with his use of evidence, so let’s shine the spotlight on his errors.

In one article he tells everyone to use public transport.

He links to the transport direct CO2 emissions calculator and says:

Private car transport is the least environmentally-friendly way to travel

But look at the assumptions he has plugged into that CO2 calculator to generate the graph showing large cars consuming way more CO2 emissions. He has calculated a journey of nearly 40 miles with a single occupant. To be honest there are really not many children driving themselves 40 miles to school every day.

So I have produced the more representative graph. I have chosen a more realistic 2 mile journey with 4 occupants, and this is the result:

So in fact for the average family school run, a small private car has significantly lower emissions than any other kind of motorised transport. Even a large family car does better than the bus, and comes in at the same emissions level as the train (assuming you have a train connecting your home and school).

Now my assumptions: 2 miles is about average in this area for the school run, but 1 and 3 miles produce almost identical results (more emissions, but the same relative emissions). I am comfortable that is accurate.

Not so firmly established is the number of occupants of the vehicles. However the CIN writer rages against primary schools in particular, and so parents must accompany the children so the minimum number of occupants is 2. 4 is actually extremely common, but there are also many vehicles with three occupants, and otehrs with more. Parents who share the school run may have up to 7 occupants in a private car.

Whilst I am comfortable with 4 in my assumption, we could find average occupancy is closer to 3. In this case the calculator shows the large private car rising to .3kg per person, worse than the train but still better than the bus. The small private car is still at the .1kg per person mark and remains far and away the most efficient means of motorised transport.

Now even though this is a rant against Caredig i Natur’s nonsense and extremely selective choice of facts, I feel duty bound to point out some assumptions in what I have said. It is clear that private cars have lowest emissions, but if a train or bus travels the journey in any case, doesn’t that mean that their pollution will be spent anyway? Shouldn’t we use public transport if the buses are already going our way?

And to that the answer is presumably yes. If the bus is already travelling the route we wish to follow, then we reduce overall emissions by taking the bus.

Of course most school runs do not start or end near public bus stops. Almost no school runs start and end near train stations. The moral here is we should not be fighting for better public transport. If we want to reduce emissions we need to do two things:

1. Encourage walking and cycling where appropriate.
2. Encourage smaller and more efficient cars

caredig i Natur will agree with my first point but he seems not to recognise there may be times when a motor vehicle is actually necessary for the school run. That is his silly assumptions blinding him again. But to more reasonable people, I think those two measures taken hand in hand could considerably help our environment, our wallets, our health and our quality of life.

An article on BBC news today informs us how we should all embrace a new test of phonics for children at age 6 as part of ensuring all children learn the phonics system systematically and early. This post is not a comment on phonics though, but rather on the terrible state of education amongst… our education ministry.

Schools Minister Nick Gibb said: “There is no doubt we need to raise standards of reading. Only last month we learnt that one in 10 boys aged 11 can read no better than a seven-year-old.

So the scandal here is that 1 in 10 boys reads well below the average seven year old. Indeed Nick Gibb is not clear whether he means the average 7 year old or one very special 7 year old, but I suspect if the latter, the numbers would be much higher than 1 in 10.

What is wrong with this statement though?

In brief: “There is no doubt we need to raise standards of reading” does not follow from the statistic we are given. Indeed, it should be entirely unsurprising that a significant proportion of boys lag their peers by this amount.

The reason for this is that in the population of all 11 year olds, there will, as in so many things, be a distribution of reading ages. That distribution ought to follow the bell shaped curve of a normal distribution, with the mean reading age being at the 11 year old mean, but notably with 10% of boys lying a little over 1 “normal distribution” from the mean (see graphic).

So what is wrong with this picture?

Well if you raise reading standards for all and by the same amount for all then all you do is move the means! In particular if all children get better at reading then the average 7 year old after the intervention may now read as an average 8 or 9 year old. The average 11 year old may also improve to the level of the average 12 or 13 year old (although as most improvement comes early, it may be that the means now are closer together). If the spread of results remains unchanged, because you improve results for all, then you would expect that you would still have 1 in 10 boys reading at the ability of the average 7 year old.

To be clear, you would not expect ANY improvement in that statistic. Indeed you might in fact expect it to worsen, as you expect the means to move closer together!

In other words, a worsening trend on that statistic could be a sign of success!

Of course, the tests can be standardised. You could call the average 7 year old attainment now as “level 7″ and not move the average ad standards improve. Then you could judge success of improvement against the level 7 baseline as well as a level 11 baseline. But that is not what the minister said, and it is not clear he understood why what he said was wrong. And this is from the education Minister!

Going wth the raw averages, the best ways to ensure no significant numbers of boys read at the mean 7 year old level, and thus achieve your education targets are:

1. Separate the means. Improvement is hard, but we can hold back 7 year olds instead. If we do not teach them to read at all until they are 7, then their mean reading age will drop, but their rapid progress thereafter should ensure that no 11 year olds read at the level of the average 7 year old.

2. Reduce the spread. That is, concentrate on the poorer readers and hold back the better ones and try to homogenise the group. One would hesitate to suggest this may be a reason why me might insist every child be forced to learn through phonics!

Plaid Cymru pushed a leaflet through my door today. The front page showed a picture of the party’s prospective candidate for the next general election – someone I know and respect, so I took the time to read the rest of the leaflet.

On the back page there was an article that quoted the Daily Mail (always a bad start!) saying that Mark Williams was all but invisible at Westminster.

Well in the information age it is easy enough to check these things. I went to the wonderful They Work for you website to look at my MP’s statistics.

Far from being invisible, the record shows he has spoken in more debates than average, has received written answers to more questions than average and has answered a high number of constituent questions quickly online. All this on reasonable expenses that are only slightly above average, and that because of travel costs, which considering the remoteness of teh constituency, is altogether reasonable.

One area that Mark Williams falls below average on is his parliamentary attendance. At 66% attendance at votes, he is a little below average here. But how much of that is related to the issues of distance, geography and relevance? So the immediate question – as Plaid Cymru is putting this information out – is how would he compare to Plaid Cymru MPs? Well again, a quick search of the Public Whip site turns up the information we need.

• Mark Williams MP, Ceredigion (LibDem) – 66.2%
• Hywel Williams MP, Caernarfon (PC) – 64.2%
• Adam Price MP, Carmarthen East & Dinefwr (PC) – 60.5%
• Elfyn Llwyd MP, Meirionnydd Nant Conwy (PC) – 63.5%

So to be clear, Mark Williams has a better voting record than any Plaid Cymru MP. A case of the pot calling the kettle black?

I don’t have a problem with Plaid Cymru. I often vote for them. But I do have a problem with misleading statements, and this surely qualifies.

A while back I wrote on a wave of Wi-Fi hysteria in the media. Since then the agitators have gone quiet, but I have been asked more than once for authorative guidance on the subject, so I am linking here the WHO factsheets on the issue.

WHO Factsheet on Electromagnetic fields and public health – Base stations and wireless technologies

WHO Factsheet on Electromagnetic fields and public health – Electromagnetic Hypersensitivity

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.