Smith alert.. on the BBC AGAIN!!!



Status
Not open for further replies.
A

Al_mossah

Guest
There was an article on Radio 4's "More or less" programme this pm (Thurs 29th Jan) , which
purports to take a look at statistics. Today they were looking at speed cameras, and had a
soundbite from our hero on it. Distressingly, probably because they limited him to a few dozen
words, he sounded almost sane.

http://news.bbc.co.uk/1/hi/programmes/more_or_less/

He argued that improvements in road safety following the placement of cameras at accident blackspots
were often entirely coincidental, and a garden gnome would have had the same effect due to the
effect known as "regression to the mean". In other words, a bad couple of years is likely to be
followed by years which are nearer to the mean.

I shall write to the BBC to suggest that if they want to use authoritative sources they may be able
to do better than our hero.

Btw, A logical extension of his argument is that speed cameras are wasted at accident blackspots.
But I thought that the anti-camera lot objected to them being anywhere but at accident blackspots!
Oh, well, why should I expect logic.

Peter.
 
al_Mossah wrote:

> I shall write to the BBC to suggest that if they want to use authoritative sources they may be
> able to do better than our hero.

I'm sure there's a joke in here somewhere about Teflon Tony and his faithful sheepdog Hutt, but the
whole thing is too depressing to contemplate. Bah!

--

Dave Larrington - http://www.legslarry.beerdrinkers.co.uk/
===========================================================
Editor - British Human Power Club Newsletter
http://www.bhpc.org.uk/
===========================================================
 
"al_Mossah" <[email protected]> wrote in message
news:[email protected]...

> Btw, A logical extension of his argument is that speed cameras are wasted
at
> accident blackspots. But I thought that the anti-camera lot objected to them being anywhere but at
> accident blackspots! Oh, well, why should I expect logic.

No, they object to them anywhere, they just pretend they don't mind them being at accident
blackspots in order to not appear quite so extreme.

cheers, clive
 
In article <[email protected]>,
"al_Mossah" <[email protected]> writes:

> He argued that improvements in road safety following the placement of cameras at accident
> blackspots were often entirely coincidental, and a

If you replace "were often" with "could be", and if you restrict the definition of "accident
blackspot" to a limited period of time (like studies using three years), then he could have a point.

> "regression to the mean". In other words, a bad couple of years is likely to be followed by years
> which are nearer to the mean.

Indeed. The argument boils down to whether what's been classified as accident blackspots are
anything more than a statistical blip.

> Btw, A logical extension of his argument is that speed cameras are wasted at accident blackspots.

Yep. They should be everywhere without discrimination.

But of course, this falls down when you consider what most local people would think of as an
accident black spot - one with a far longer history of trouble than just the three years.

--
Nick Kew
 
On Thu, 29 Jan 2004 19:05:26 +0000, [email protected] (Nick Kew)
wrote:

>this falls down when you consider what most local people would think of as an accident black spot -
>one with a far longer history of trouble than just the three years.

Quite - and these are the places where locals often campaign long and hard for erection of a camera.

Guy
===
May contain traces of irony. Contents liable to settle after posting.
http://chapmancentral.demon.co.uk
 
al_Mossah <[email protected]> wrote:

: He argued that improvements in road safety following the placement of cameras at accident
: blackspots were often entirely coincidental, and a garden gnome would have had the same effect due
: to the effect known as "regression to the mean".

Sigh. This is were general bad understanding of basic stats hurt.

The obvious next question should have been

"So, if a road had a 30 m hole in it just round a blind bend, would accidents there revert to
the mean?"

Sigh. Again.

Arthur

--
Arthur Clune http://www.clune.org "Technolibertarians make a philosophy out of a personality defect"
- Paulina Borsook
 
On Thu, 29 Jan 2004 20:57:20 +0000, "Just zis Guy, you know?"
<[email protected]> wrote:

>On Thu, 29 Jan 2004 19:05:26 +0000, [email protected] (Nick Kew) wrote:
>
>>this falls down when you consider what most local people would think of as an accident black spot
>>- one with a far longer history of trouble than just the three years.
>
>Quite - and these are the places where locals often campaign long and hard for erection of
>a camera.
>

The rules regarding placement of cameras really annoys me. But, sadly, this requirement for blood on
the road is pretty standard when attempting to get any highway intervention. Traffic calming, ped
crossings etc; unless you can demonstrate the road is actively killing people (you know what I
mean), nothing will get done.

Locals are quite understandably disappointed to be told that the three cars that have landed in
their living room in the past year don't count.

The answer to how many people have to die before the law even stands a chance of being enforced is
3. Within 100 yards. Within 3 years.
 
There is a particularly clue-free pair of cameras near Larrington Towers. They are situated near a
corner where there have been numerous RTAs. A couple of years ago They realised that this was a
dodgy corner and resurfaced the eastbound lane with high-grip Stuff. However, a Several of months
after that, They resurfaced the whole road and didn't replace the high-grip Stuff. Doh!

Anyway, They also put in cameras, one facing in either direction. The one acting on the
westbound lane is before the corner, as the point is to ensure drivers slow down before reaching
the said corner. The one in the eastbound lane is /after/ the corner, as the point is to ensure
that, er, hang on.

--

Dave Larrington - http://www.legslarry.beerdrinkers.co.uk/
===========================================================
Editor - British Human Power Club Newsletter
http://www.bhpc.org.uk/
===========================================================
 
"[Not Responding]" <[email protected]> wrote in message
news:[email protected]...

> The rules regarding placement of cameras really annoys me. But, sadly, this requirement for blood
> on the road is pretty standard when attempting to get any highway intervention.

It is my understanding (and you will know more about this than I) that in the Olden Days a 30 limit
in a village required the usual justification-by-carnage, and these rules were changed. Drivers now
bleat about the plethopra of 30 limits in places they hadn't noticed there were houses (presumably
because they were going too fast to see them) and the result is a move back to the old blood-and-
gore criteria, as seen with camera placements.

Is it necessary to demonstrate a certain level of muggings before installling CCTV in a town centre?
I think not. Time to challenge the absurd pretence that speeding isn't /really/ illegal.

--
Guy
===

WARNING: may contain traces of irony. Contents may settle after posting.
http://www.chapmancentral.co.uk
 
Just zis Guy, you know? wrote:
> Time to challenge the absurd pretence that speeding isn't /really/
illegal.

Or victimless, not only from the potential injury and loss of life in crashes, but also due to the
excess noise and pollution and intimidatory effects on non motor users.

--
Andy Morris

AndyAtJinkasDotFreeserve.Co.UK

Love this:
Put an end to Outlook Express's messy quotes
http://home.in.tum.de/~jain/software/oe-quotefix/
 
On Thu, 29 Jan 2004 20:57:20 +0000, "Just zis Guy, you know?"
<[email protected]> wrote:

>>this falls down when you consider what most local people would think of as an accident black spot
>>- one with a far longer history of trouble than just the three years.
>
>Quite - and these are the places where locals often campaign long and hard for erection of
>a camera.

Hi Guy

ISTM that many want cameras in or near their own little village but object to them elsewhere. A
YIMBY/NIMBY state of affairs.

Being silly for a mo. ... Taking PS's argument to the extreme (I'm assuming I heard him correctly),
there should be cameras everywhere apart from in accident blackspots.

James
 
On Sat, 31 Jan 2004 20:29:33 +0000, James Hodson
<[email protected]> wrote:

>Being silly for a mo. ... Taking PS's argument to the extreme (I'm assuming I heard him correctly),
>there should be cameras everywhere apart from in accident blackspots.

If I understand his argument correctly it is that a reduction in accidents could be due only to one
of two things: the cameras or regression to the mean. As he has demonstrated that cameras increase
accidents, that only leaves regression to the mean, and all accident blackspots must therefore be
due to a statistical blip.

Is that it?

--
Dave...

Get a bicycle. You will not regret it. If you live. Mark Twain
 
Just zis Guy, you know? wrote:
> "[Not Responding]" <[email protected]> wrote in message
> news:[email protected]...
>
>
> Is it necessary to demonstrate a certain level of muggings before installling CCTV in a town
> centre? I think not.

Wrong!

30seconds on google turned up

http://216.239.59.104/search?q=cache:TTAQzs37qtMJ:www.ne-
erbyshire.gov.uk/EasySite/lib/serveDocument.asp%3Fdoc%3D453%26pgid%3D773+cctv+criteria&hl=en&ie=UTF-
8

aFbl3ZP2wJ:www.cambridge.gov.uk/councillors/agenda/2002/1111strat/09.pdf+cctv+criteria&hl=en&ie=UTF-
8

from the second one:

one of the criteria to justify a scheme:

The proposal relates to an area which has a higher than average crime rate of types of crime where
CCTV has a proven role in prevention or detection (or both). Evidence of crime in the area should be
capable of demonstration by hard evidence, rather than anecdote. CCTV should not be used simply to
reduce the fear of crime. The problem(s) which CCTV is intended to address should be clearly
defined, so that an assessment can be made of its likely success in dealing with the problem(s

pk
 
On Sun, 01 Feb 2004 15:19:20 +0000, Dave Kahn <[email protected]>
wrote:

>If I understand his argument correctly it is that a reduction in accidents could be due only to one
>of two things: the cameras or regression to the mean. As he has demonstrated that cameras increase
>accidents, that only leaves regression to the mean, and all accident blackspots must therefore be
>due to a statistical blip.
>
>Is that it?

It could be be so, Dave. At least that's how I understand it to be.

There will always be some road deaths in this country; perhaps (approximately) three thousand is
that figure.

James
 
Status
Not open for further replies.

Similar threads

C
Replies
32
Views
1K
I
S
Replies
1
Views
431
T
T
Replies
0
Views
664
T
M
Replies
0
Views
437
M
N
Replies
4
Views
378
P
R
Replies
0
Views
351
R
T
Replies
267
Views
5K
B