Safe Speed Forums

The campaign for genuine road safety
It is currently Sun Apr 26, 2026 17:45

All times are UTC [ DST ]




Post new topic Reply to topic  [ 123 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6, 7  Next
Author Message
 Post subject:
PostPosted: Thu Dec 20, 2007 01:33 
Offline
Final Warning
Final Warning

Joined: Fri Oct 26, 2007 23:59
Posts: 280
hjeg2 wrote:
I didn't say that they were, but they are much better than nothing.


smeggy wrote:
Posted: Mon Dec 10, 2007 9:02 am
Please explain why you believe that to be.


hjeg2 wrote:
Posted: Mon Dec 10, 2007 7:40 pm
… I have seen figures that show that RTTM isn't the case; it's somewhere between that and the original DfT figures. In other words, speed cameras do have an effect.


[Then I mentioned ‘bias on selection’ where I thought that you meant something else.]

hjeg2 wrote:
A good example of where in my opinion they are much better than nothing is the A3 which is a three-laned road in west London. It used to have a 70 limit but now has a 50 limit, backed up by fairly frequent speed cameras. You used to get quite a lot of KSIs on it.


As we now know, the figures that I was talking about were the ones in George Monbiot’s article. The “original DfT figure” was something like a fall of 35% in KSIs attributed to speed cameras. When talking about RTTM like this there is/was an implication, even if you didn’t mean it, that RTTM is the sole cause of this fall – this is why I said above that “RTTM isn’t the case”.


Ah, now continuing down this thread I come on to the first of Robin’s posts. Well, well, well, it does seem, everyone (but especially Bombus, Smeggy and Robin), that it was Robin to start the pointless posts. I expect that Bombus and Smeggy will wish to criticise him for doing so, right?

Here are some of the points (or ‘points’ if you prefer) that I asked him which he then dodged:
hjeg2 wrote:
1. Oh right, so it's okay for you to make random 'points' which have no bearing whatsoever on the topic being discussed, but it's not okay for me to do the same?

2. What bearing does the following have then?
"Didn't take long to resume cutting up posts and answering points in isolation, and with no meaning, did it?"

3. And why did you say this:
"So where are these figures that debunk RTTM?" when I had already said this: "I'm afraid I can't remember where they were from"

4. And why bother saying this:
"The reason your avenue of debate has become vapid is that your only rebuttal is "some stats you saw, that were recent, but you can't remember where"." Who said it was meant to be a rebuttal?

5. Why say this:
"Physician..." What has that got to do with road safety?

6. Why say this:
"....and another!!"

7. And finally (I think), why put the "2" in hjeg2 in bold? You did it, not me, and now I'm just asking why.


It’s no good just saying that the above is “arguing about arguing” when it was Robin who came out with the comments that I am merely responding to.


Here are some points of Robin’s which I always intended to come back to, just as soon as I could get past the irrelevant rubbish that he comes out with:

Robin wrote:
There is plenty to read about RTTM on this site, if you venture outside the forum, and its a very simple concept to understand: If a road is accident free for a significant period, and then in one year there is a single incident in which 4 people, in the same vehicle, die, then siting a camera there does not mean that the following year's lack of fatalities is due in any part to the presence of the camera. Given that this is exactly how speed cameras have been sited, its not too hard to see that it must apply! The DfT's own report contained an acceptance of RTTM, albeit hidden in an annex, and there have been other, independent, reports pointing to it's significance.


No-one is arguing that RTTM doesn’t exist. Coming out with the above just shows how Robin is either confused or is, as usual, trying to engineer an argument with me. The point is whether RTTM is responsible just by itself for the reduction of collisions after a speed camera has been installed. [Have patience; I shall come back to this.]

Robin wrote:
More Police Officers - Speed cameras are not the only ill effect of current policy, the targets imposed on the police service also play a large part. The current administration is obsessed with measurement, even if the things they can measure are not really that important. Thus a speeding ticket issued counts as a crime detected and solved, a double tick.


This is another paragraph by Robin which only has a passing reference to the actual issues at hand. Yes, the targets, at least as they are now, are wrong. And the thing is, according to an article in The Times, is that there aren’t targets for motoring offences! This is why I say, and the police say, that even if we got rid of speed cameras we still wouldn’t get any more police on the roads.


smeggy wrote:
Posted: Wed Dec 12, 2007 2:19 pm
I presume you agree that I did not “clearly wanted to talk about stats”.


No because you said:

smeggy wrote:
Why should a lack of peer review prevent you from ‘arguing statistics’? If that's the case why are you here posting on this forum?


In other words if I wasn’t willing to argue statistics then I shouldn’t be on this forum – I took that, perhaps wrongly, to mean that you wanted to talk about stats.

As for the issue of peer review, I think we should now drop that for obvious reasons.

smeggy wrote:
We have "some police", but fewer on the roads than before, needlessly so because of the huge amount of paperwork they now have to do. The increased of cameras fooled people into thinking their loss was compensated; however, the continued loss of the nationwide fatality trend proves the folly of it.
Hence we can have more police on the roads without being "at the detriment of other crimes".


I think that even if the amount of paperwork that the police have to do was reduced, you would still not have as many police on the roads as before because of the public moaning that they should concentrate on ‘real’ crime.

smeggy wrote:
Well I never, RTTM is proven, accepted and extremely significant, and that’s excluding other effects of bias on selection …


I don’t recall ever saying that RTTM wasn’t those things!

But we now get to a very important point:


You have very conveniently decided that that entire 10% “overall average reduction in FSCs attributable to these cameras” is not down to the cameras but instead is down to bias on selection.

Warning, warning!!! Alert, alert!!!


I can now see what you and Bombus have been alluding to for a while – that there is in fact a reduction in fatal and serious collisions of (up to) 10%!!! Well you hardly rushed to say that now did you!

Yes, now that I know that, it certainly would be good to conduct research into what difference other measures make, but until then, I really don’t see how you can claim that speed cameras have no effect when you simply can’t say for sure.

And tell me, Smeggy, if I can’t trust you to be consistent and fair in your moderation, how can I possibly trust that you are telling me the whole truth when it comes to your sources?

smeggy wrote:
No, you are clearly trying to put words into my mouth.


Rubbish. I was merely asking you a question.

smeggy wrote:
I am explaining to you bias on selection. The A3 example is likely to be mostly RTTM (as explained). The limit drop may not have been significant at all; furthermore it isn’t the only example of bias on selection.


Except that I’ve told you that the A3 is a three-laned road. There aren’t any extra traffic calming features. There hasn’t been, to the best of my knowledge, any local road safety awareness courses. What else could there have been?

smeggy wrote:
No, I said it could play a part: "even if true". Are you trying to misrepresent me?


Smeggy, I never try to misrepresent anyone.

smeggy wrote:
I said that in response to you saying that it "will" play a part. I asked you to justify the "will" in your statement. I presume anything of relevance still won’t be forthcoming.


No of course it won’t be; as I said before, I just assumed that that would be one of the things that you would say had played a part. I was saying it so that you didn’t have to. Your negativity really is completely unfounded here.

smeggy wrote:
Do you now understand bias on selection and that it is separate from RTTM and additional to the illusion of perceived effectiveness of cameras?


Yes, thank you.

smeggy wrote:
Are you not concerned that figures exist for the effectiveness of speed cameras but no such figures exist for other safety measures, even though they exist at cameras sites?


I am now, yes.

smeggy wrote:
Isn’t that exactly what you get with RTTM? If so then explain the difference.


No what I was talking about was getting less accidents than the short period beforehand on which it is decided to put up a speed camera – so less accidents overall.



Posted: Wed Dec 12, 2007 8:21 pm
In reply to r11co:
“Er, moderator, ad hominem alert”
Also:
“moderator, another ad hominem”

Smeggy, why have you taken no action over the above?

_________________________


Right, it’s taken a long time to put the above all together, so I shall have to leave any other comments for now. I do hope you all enjoy the sentence in bold. I certainly did.

_________________
Before you moan about middle-lane hoggers, check that you yourself are obeying all the rules of the road.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Thu Dec 20, 2007 08:57 
Offline
User
User avatar

Joined: Sat Aug 13, 2005 23:28
Posts: 1940
hejeg2 wrote:

Quote:
A good example of where in my opinion they are much better than nothing is the A3 which is a three-laned road in west London. It used to have a 70 limit but now has a 50 limit, backed up by fairly frequent speed cameras. You used to get quite a lot of KSIs on it.



As we now know, the figures that I was talking about were the ones in George Monbiot’s article. The “original DfT figure” was something like a fall of 35% in KSIs attributed to speed cameras. When talking about RTTM like this there is/was an implication, even if you didn’t mean it, that RTTM is the sole cause of this fall – this is why I said above that “RTTM isn’t the case



But you still do not know whether the cam ist "preventingthe incidents" or whether the 50 mph ist "preventing the incidents" :popcorn: especially since 50 mph head on in the shared overtaking lane will also cause a bad nasty.


If they really wanted to prevent incidents .. then perhaps re-engineering this road by making each carriageway wider two way would be better as I think people tend to "think through" the overtake better than if a specific lane which can cause two to pull out und completely mis -read the situation.

They engineer most of these out up North.. without lowering limits on some roads. That stretch of A6 ist still NSL ;)


By the way - if this was single carriageway road as a 3 laner would be.. then it would be 60 mph NSL surely - nicht? :popcorn:

_________________
Nicht ganz im Lot!
Ich setze mich immer wieder in die Nesseln! Der Mad Doc ist mein Mann! Und ich benutzte seinen PC!

UND OUR SMILEYS? Smile ... und the the world smiles with you.
Smiley guy seen when you read
Fine me for Safe Speed
(& other good causes..)

Greatest love & Greatest Achievements Require Greatest Risk
But if you lose the driving plan - don't lose the COAST lesson.
Me?
Je ne regrette rien
!


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Thu Dec 20, 2007 09:52 
Offline
Friend of Safe Speed
Friend of Safe Speed
User avatar

Joined: Tue Mar 09, 2004 23:09
Posts: 6737
Location: Stockport, Cheshire
WildCat wrote:
If they really wanted to prevent incidents .. then perhaps re-engineering this road by making each carriageway wider two way would be better as I think people tend to "think through" the overtake better than if a specific lane which can cause two to pull out und completely mis -read the situation.

They engineer most of these out up North.. without lowering limits on some roads. That stretch of A6 ist still NSL ;)


By the way - if this was single carriageway road as a 3 laner would be.. then it would be 60 mph NSL surely - nicht? :popcorn:

Just to clarify, it's a dual carriageway with 3 lanes each way (D3) not a single carriageway with 3 lanes (S3).

_________________
"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Thu Dec 20, 2007 12:45 
Offline
Gold Member
Gold Member

Joined: Thu Nov 09, 2006 14:06
Posts: 3654
Location: Oxfordshire
hjeg2 wrote:
No-one is arguing that RTTM doesn’t exist. Coming out with the above just shows how Robin is either confused or is, as usual, trying to engineer an argument with me. The point is whether RTTM is responsible just by itself for the reduction of collisions after a speed camera has been installed. [Have patience; I shall come back to this.]


It is probable that, at many discrete sites, RTTM is responsible for the entire reduction, as there just aren't sufficient numbers of KSIs (before and/or after treatment) to apportion causation to anything else. I'm not sure where you have got the 10% figure from, but its my recollection that 10% was quoted in one study as the proportion of the claimed benefit that remained after RTTM was taken into account, not the proportion of the total. 10% of the total after RTTM might be a little optimistic, given that less than 5% of accidents are caused by exceeding a speed limit.

Interesting to see that even attempting rational debate you cannot avoid adding barbs, but your effort is appreciated!

hjeg2 wrote:
And tell me, Smeggy, if I can’t trust you to be consistent and fair in your moderation, how can I possibly trust that you are telling me the whole truth when it comes to your sources?


Package-deal fallacy, this carries equal logical veracity:

If I can't trust you to conduct rational debate without resorting to ad hominem, how can I possibly trust you to wash regularly? Ergo you smell bad.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Thu Dec 20, 2007 13:30 
Offline
Friend of Safe Speed
Friend of Safe Speed
User avatar

Joined: Sun Sep 25, 2005 10:16
Posts: 7986
Location: Moved to London
hjeg2 wrote:
I think that even if the amount of paperwork that the police have to do was reduced, you would still not have as many police on the roads as before because of the public moaning that they should concentrate on ‘real’ crime.

I disagree. I believe have more police than ever before (as well as other ‘services’), we just don’t see them; we can have more tackling ‘real’ crime, both on and off the roads.

hjeg2 wrote:
As we now know, the figures that I was talking about were the ones in George Monbiot’s article. The “original DfT figure” was something like a fall of 35% in KSIs attributed to speed cameras. When talking about RTTM like this there is/was an implication, even if you didn’t mean it, that RTTM is the sole cause of this fall – this is why I said above that “RTTM isn’t the case”.

I’ve shown Monbiot’s article to be misleading (as well as based on erroneous claims).

Now I understand your confusion. I don’t know how but you have wrongly inferred (from me?) that RTTM is the sole cause of reductions. I have been clear on that point within several posts earlier on: "The figures put the RTTM portion at between 2/3 to 3/4 of the gross reduction…", I even quoted from the forth year report for you. If you feel I have been unclear than please say where and I will modify the post accordingly.

hjeg2 wrote:
No-one is arguing that RTTM doesn’t exist. Coming out with the above just shows how Robin is either confused or is, as usual, trying to engineer an argument with me. The point is whether RTTM is responsible just by itself for the reduction of collisions after a speed camera has been installed. [Have patience; I shall come back to this.]

No it isn’t, it never was. The actual point is why you believe speed cameras are "much better than nothing", especially given the significance of RTTM, the long-term trend and the unaccounted effects of ‘bias on selection’.

hjeg2 wrote:
You have very conveniently decided that that entire 10% “overall average reduction in FSCs attributable to these cameras” is not down to the cameras but instead is down to bias on selection.

Warning, warning!!! Alert, alert!!!


I can now see what you and Bombus have been alluding to for a while – that there is in fact a reduction in fatal and serious collisions of (up to) 10%!!! Well you hardly rushed to say that now did you!

I have not decided any such claim. I repeat from much earlier in our discussion: "so leaving 1/3 to 1/4 of the claimed reduction seemingly genuinely attributable to speed cameras. However, the resultant 'genuine reduction' did not take into account 'bias on selection'. ". Perhaps you simply missed it or forgot it?

hjeg2 wrote:
Smeggy, I never try to misrepresent anyone.

OK I’ll take your word for that, but that doesn’t mean you haven’t inadvertently succeeded.

hjeg2 wrote:
Rubbish. I was merely asking you a question.

Your wording indicated that I was making an (erroneous) claim: "…are you trying to claim that… ". The direct answer to your question is obviously no. Another one…

hjeg2 wrote:
Yes, now that I know that, it certainly would be good to conduct research into what difference other measures make, but until then, I really don’t see how you can claim that speed cameras have no effect when you simply can’t say for sure.

Let’s be clear that I have made no such claim. My actual words (in full) were: "Given RTTM, 'bias on selection' and the accident stats, it is hard to understand how they can be of any significant benefit at all. Couple that with the negative side effects and you have to wonder if they really are better than nothing, let alone much better. ". As you can see, no such claim was put forward.

hjeg2 wrote:
Except that I’ve told you that the A3 is a three-laned road. There aren’t any extra traffic calming features. There hasn’t been, to the best of my knowledge, any local road safety awareness courses. What else could there have been?

An awareness campaign need not be limited to local road safety courses. Drivers knowing that there was a serious accident in an area may prompt them to drive more cautiously in that area. There are usually signs installed following such accidents asking for witnesses of such events.

hjeg2 wrote:
smeggy wrote:
I said that in response to you saying that it "will" play a part. I asked you to justify the "will" in your statement. I presume anything of relevance still won’t be forthcoming.

No of course it won’t be; as I said before, I just assumed that that would be one of the things that you would say had played a part. I was saying it so that you didn’t have to. Your negativity really is completely unfounded here.

In short: you cannot substantiate your comment. I think we can leave it at that.

hjeg2 wrote:
smeggy wrote:
Isn’t that exactly what you get with RTTM? If so then explain the difference.

No what I was talking about was getting less accidents than the short period beforehand on which it is decided to put up a speed camera – so less accidents overall.

No you weren’t. The term ‘short’ has come from nowhere; you’re twisting your argument.

To remind you: your actual words were " A good example of where in my opinion they are much better than nothing is the A3 which is a three-laned road in west London. It used to have a 70 limit but now has a 50 limit, backed up by fairly frequent speed cameras. You used to get quite a lot of KSIs on it."

I say again: Isn’t that exactly what you get with RTTM? If not then explain the difference - and I do mean explain the difference.

hjeg2 wrote:
As for the issue of peer review, I think we should now drop that for obvious reasons.

The thread has been reopened. It has been decided that there’s nothing to stop us discussing it. Feel free to answer my posts on the issue, by PM if necessary.



Now to end on something positive:
hjeg2 wrote:
smeggy wrote:
Do you now understand bias on selection and that it is separate from RTTM and additional to the illusion of perceived effectiveness of cameras?


Yes, thank you.

smeggy wrote:
Are you not concerned that figures exist for the effectiveness of speed cameras but no such figures exist for other safety measures, even though they exist at cameras sites?


I am now, yes.

Thanks for your honesty. Interestingly, we’ve almost come full circle.

Given that the best study on the subject has shown that 10% (absolute) of the KSI fall is due to speed cameras, but that ‘bias on selection’ exists and was unaccounted for, do you agree that the 10% figure must also be optimistic and that the figure could (probability aside) actually be 0%, or even negative? If not then why not?

_________________
Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Thu Dec 20, 2007 21:47 
Offline
User
User avatar

Joined: Sat Aug 13, 2005 23:28
Posts: 1940
PeterE wrote:
WildCat wrote:
If they really wanted to prevent incidents .. then perhaps re-engineering this road by making each carriageway wider two way would be better as I think people tend to "think through" the overtake better than if a specific lane which can cause two to pull out und completely mis -read the situation.

They engineer most of these out up North.. without lowering limits on some roads. That stretch of A6 ist still NSL ;)


By the way - if this was single carriageway road as a 3 laner would be.. then it would be 60 mph NSL surely - nicht? :popcorn:

Just to clarify, it's a dual carriageway with 3 lanes each way (D3) not a single carriageway with 3 lanes (S3).



Ach.. so we back to blinkered stupidity as in "reduce limit.. whack up speed cam"

But we still have no tangible evidence as to whether or not this road regressed to mean (more likely).. became less busy as folk hate cams ..und we do not know if other roads around are experiencing incident. I suspect the latter as the KSI to local hospitals does not tally with the claims as made by the prats :popcorn:

All we do ist move a problem around. We not solving it. Only police und education can make in-road into this problem... und we have to SPEND money sometimes to SAVE money und have those lives MAKING us MONEY :wink:

Bluntly.. we are an economic commodity first to the government.. cannon fodder .. but very human und much loved by famuly/pals - including virtual ones on these media :wink:

_________________
Nicht ganz im Lot!
Ich setze mich immer wieder in die Nesseln! Der Mad Doc ist mein Mann! Und ich benutzte seinen PC!

UND OUR SMILEYS? Smile ... und the the world smiles with you.
Smiley guy seen when you read
Fine me for Safe Speed
(& other good causes..)

Greatest love & Greatest Achievements Require Greatest Risk
But if you lose the driving plan - don't lose the COAST lesson.
Me?
Je ne regrette rien
!


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Thu Dec 20, 2007 21:55 
Offline
User
User avatar

Joined: Sat Aug 13, 2005 23:28
Posts: 1940
By the way.. Stevienbabes und the other pratsters get all uptight over posts like mine..


because they cannot refute them. The stats show that KSI on the roads are not down.. we just moved the problem to another road .. which again backs RTTM on targeted roads too :popcorn:

IG right when he move the RPU around und use the police intelligence properly. One third less KSI as constant :bow: They must be doing something right there. But they have police.. not cams.. hmmmmm ! :scratchchin:

Paulie hat Recht! :love:

_________________
Nicht ganz im Lot!
Ich setze mich immer wieder in die Nesseln! Der Mad Doc ist mein Mann! Und ich benutzte seinen PC!

UND OUR SMILEYS? Smile ... und the the world smiles with you.
Smiley guy seen when you read
Fine me for Safe Speed
(& other good causes..)

Greatest love & Greatest Achievements Require Greatest Risk
But if you lose the driving plan - don't lose the COAST lesson.
Me?
Je ne regrette rien
!


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Fri Dec 21, 2007 07:34 
Offline
Final Warning
Final Warning

Joined: Fri Oct 26, 2007 23:59
Posts: 280
smeggy wrote:
hjeg2 wrote:
smeggy wrote:
Isn’t that exactly what you get with RTTM? If so then explain the difference.

No what I was talking about was getting less accidents than the short period beforehand on which it is decided to put up a speed camera – so less accidents overall.

No you weren’t. The term ‘short’ has come from nowhere; you’re twisting your argument.


I'm not twisting my argument. Sure, I've now used the word "short", but that was only because I clearly wasn't getting the point across before, despite saying it several times. I have always meant the same thing, even if it didn't come across right.

smeggy wrote:
To remind you: your actual words were " A good example of where in my opinion they are much better than nothing is the A3 which is a three-laned road in west London. It used to have a 70 limit but now has a 50 limit, backed up by fairly frequent speed cameras. You used to get quite a lot of KSIs on it."

I say again: Isn’t that exactly what you get with RTTM? If not then explain the difference - and I do mean explain the difference.


No because the mean in this subject is the long-term average, right? And the 'baseline' period is the three-year period beforehand, right? So if the number of collisions was regressing to the long-term average then it would be going back to the number before the 'baseline' period, wouldn't it?

And then I said above that you "used to get quite a lot of KSIs on it", in other words that there were more KSIs on it in the years before simply the baseline period than there are now. Remember here that speed cameras have only been in widespread use for a short number of years.

_________________
Before you moan about middle-lane hoggers, check that you yourself are obeying all the rules of the road.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Fri Dec 21, 2007 08:58 
Offline
User
User avatar

Joined: Sat Aug 13, 2005 23:28
Posts: 1940
hjeg2 wrote:
smeggy wrote:
hjeg2 wrote:
smeggy wrote:
Isn’t that exactly what you get with RTTM? If so then explain the difference.

No what I was talking about was getting less accidents than the short period beforehand on which it is decided to put up a speed camera – so less accidents overall.

No you weren’t. The term ‘short’ has come from nowhere; you’re twisting your argument.


I'm not twisting my argument. Sure, I've now used the word "short", but that was only because I clearly wasn't getting the point across before, despite saying it several times. I have always meant the same thing, even if it didn't come across right.





So you are :scratchchin: talking about the criteria which say that the site has to have 4 deaths in the preceding 3 years for scam...


So we have one London road which Kevin Delaney (who placed the first one) passed comment that one camera claim 100% "efficiency" because 4 die in ONE SINGLE CAR which collide with tree. (Was a kid who had nicked the car by the way.. so not quite the "speeder" who gets "disciplined" by a NIP or an offered Speed Aware/DIS course. :roll:


No accident/collision or whatever occurr there before or after.. but the spot qualified under the rigid interpretation of the rules as opposed to common sense leading the logic. :roll:


There are others..... (the best one was Cambs claiming justification for a mobile because of 400 KSI on that spot on that day over past 4 years. An outrageous fibble as no hospital in the county had treated so many on one single day und even if this spread over 365 days over the previous 5 years - it show perhaps that the road must have some very different problem which can be resolved by some civil engineering or lick of tarmac paints.)


But Lancs at height of scam infestation was whacking up cams over slightest shunt over a some other bending of the "guidelines".

Small wonder then that there can be claims of

:listenup: See how effective our lovely scams are - )(really meaning flashing the tills as opposed to the county having less RTACS brought into A&E :roll: )

Then there ist the rather dodgy way of collating the data. Pennington acknowledged this when he found "cam efficiency of decreasing incident ranged from 17% to 70%" with there being no system of collating the raw data.. so again - "they" dupe the gullible public into accepting less police und more danger of losing a driving licence from the smallest of margin which the old police from even the "Life on Mars" era would not dunk a doughnut for.

We then have Paul's research which took something as "constant" - und the calculations - no matter how you play around with them - come back to RTTM on many high profile sites .. which incidentally are placed not at where any accident occurred ,.. but on the very roads where the police used to lurk as they knew someone would be tempted to drive above the lolly because of the nice wide clear straight nature of the road.

Past history then has nothing to do with it. Ings had police lurkers long before Steviebabes upped periscope here. :popcorn: It just that the sites have history of revenue .,,, :popcorn:


Folk ain't as daft as the dumbed down Maths exams try to make them. :wink:

Quote:
smeggy wrote:
To remind you: your actual words were " A good example of where in my opinion they are much better than nothing is the A3 which is a three-laned road in west London. It used to have a 70 limit but now has a 50 limit, backed up by fairly frequent speed cameras. You used to get quite a lot of KSIs on it."

I say again: Isn’t that exactly what you get with RTTM? If not then explain the difference - and I do mean explain the difference.


No because the mean in this subject is the long-term average, right? And the 'baseline' period is the three-year period beforehand, right? So if the number of collisions was regressing to the long-term average then it would be going back to the number before the 'baseline' period, wouldn't it?

And then I said above that you "used to get quite a lot of KSIs on it", in other words that there were more KSIs on it in the years before simply the baseline period than there are now. Remember here that speed cameras have only been in widespread use for a short number of years.



But not saving anything like as claimed. Accidents have chance element in them.. set of particular circumstances which all combine.


The criteria used for setting up a scam has been "loosely interpreted" without paying attention to actual common sense or worse with the idea of building up a nice little business. One single freak incident has met the required number of KSI at one fell swoop in many cases - which again skews up any chance of accurate measurement.

_________________
Nicht ganz im Lot!
Ich setze mich immer wieder in die Nesseln! Der Mad Doc ist mein Mann! Und ich benutzte seinen PC!

UND OUR SMILEYS? Smile ... und the the world smiles with you.
Smiley guy seen when you read
Fine me for Safe Speed
(& other good causes..)

Greatest love & Greatest Achievements Require Greatest Risk
But if you lose the driving plan - don't lose the COAST lesson.
Me?
Je ne regrette rien
!


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Fri Dec 21, 2007 11:33 
Offline
Friend of Safe Speed
Friend of Safe Speed
User avatar

Joined: Sun Sep 25, 2005 10:16
Posts: 7986
Location: Moved to London
hjeg2 wrote:
No because the mean in this subject is the long-term average, right? And the 'baseline' period is the three-year period beforehand, right? So if the number of collisions was regressing to the long-term average then it would be going back to the number before the 'baseline' period, wouldn't it?

It took you a long time to get there. Anyway, at least we understand each other now.

To confirm, you’re defining the long term average to be that before (not including) the nominal 3 year baseline – in principle that’s OK. Unfortunately there are two counfounding factors at play.

Long-term trend: the national KSI level was falling anyway due to many other factors; you can expect (on average) a KSI fall at all sites all over the country anyway. The forth year report puts that figure at 10% over the 3 year baseline period, this figure will of course be higher if one is to go back further than the 3 year period (which you have). A new baseline prior to the nominal 3 year baseline would put as back on a steeper part of the national KSI curve. If assuming another 3 year baseline immediately preceding the nominal 3 year baseline, we can expect long-term trend to account for significantly more than 20% (absolute) of any drop.

Furthermore, ‘bias on selection’ cannot be discounted (as explained in my previous post). There is no data regarding the significance of this. We’ve already agreed this is real and an issue of concern, I suspect this is another significant driver.

hjeg2 wrote:
And then I said above that you "used to get quite a lot of KSIs on it", in other words that there were more KSIs on it in the years before simply the baseline period than there are now. Remember here that speed cameras have only been in widespread use for a short number of years.

Do you have figures for that site or was it just a gut feeling?

_________________
Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Fri Dec 21, 2007 21:46 
Offline
Final Warning
Final Warning

Joined: Fri Oct 26, 2007 23:59
Posts: 280
smeggy wrote:
hjeg2 wrote:
No because the mean in this subject is the long-term average, right? And the 'baseline' period is the three-year period beforehand, right? So if the number of collisions was regressing to the long-term average then it would be going back to the number before the 'baseline' period, wouldn't it?

It took you a long time to get there.


Or rather it took you a long time to get there. I have always meant the same thing.

smeggy wrote:
Anyway, at least we understand each other now.

To confirm, you’re defining the long term average to be that before (not including) the nominal 3 year baseline – in principle that’s OK. Unfortunately there are two counfounding factors at play.

Long-term trend: the national KSI level was falling anyway due to many other factors; you can expect (on average) a KSI fall at all sites all over the country anyway. The forth year report puts that figure at 10% over the 3 year baseline period, this figure will of course be higher if one is to go back further than the 3 year period (which you have). A new baseline prior to the nominal 3 year baseline would put as back on a steeper part of the national KSI curve. If assuming another 3 year baseline immediately preceding the nominal 3 year baseline, we can expect long-term trend to account for significantly more than 20% (absolute) of any drop.

Furthermore, ‘bias on selection’ cannot be discounted (as explained in my previous post). There is no data regarding the significance of this. We’ve already agreed this is real and an issue of concern, I suspect this is another significant driver.


But how do you know that these 'bias on selection' factors aren't actually responsible for part of the general downward trend? In other words that they aren't already in effect included?

smeggy wrote:
hjeg2 wrote:
And then I said above that you "used to get quite a lot of KSIs on it", in other words that there were more KSIs on it in the years before simply the baseline period than there are now. Remember here that speed cameras have only been in widespread use for a short number of years.

Do you have figures for that site or was it just a gut feeling?


It was just a gut feeling.

_________________
Before you moan about middle-lane hoggers, check that you yourself are obeying all the rules of the road.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Fri Dec 21, 2007 22:01 
Offline
Final Warning
Final Warning

Joined: Fri Oct 26, 2007 23:59
Posts: 280
WildCat wrote:
Past history then has nothing to do with it. Ings had police lurkers long before Steviebabes upped periscope here. :popcorn: It just that the sites have history of revenue .,,, :popcorn:

Folk ain't as daft as the dumbed down Maths exams try to make them. :wink:


I've cut a load of the waffle out... :)

I have no idea what or who "Steviebabes" is, but the study that Smeggy is quoting shows that speed cameras do affect what has happened in the past history.

The study showed that speed cameras on average cut fatal and serious collisions by 10%. It's worth noting that that breaks down into 9% for mobile speed cameras and 17% for fixed cameras. A lesson here, perhaps?

WildCat wrote:
But not saving anything like as claimed. Accidents have chance element in them.. set of particular circumstances which all combine.


I refer you to what I wrote above. Also, you will note that I try to avoid talking about "accidents", and instead talk about "collisions". There are what I would call genuine accidents and avoidable accidents.

WildCat wrote:
The criteria used for setting up a scam has been "loosely interpreted" without paying attention to actual common sense or worse with the idea of building up a nice little business. One single freak incident has met the required number of KSI at one fell swoop in many cases - which again skews up any chance of accurate measurement.


But how come there are so many of these "single freak incidents" then? We now have 6,000 (fixed?) speed cameras in place now don't we?

As for the nice little business point, how about if, instead of being done for speeding when caught by a yellow speed camera, you get done for driving without due care and attention?

_________________
Before you moan about middle-lane hoggers, check that you yourself are obeying all the rules of the road.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Fri Dec 21, 2007 22:30 
Offline
Friend of Safe Speed
Friend of Safe Speed
User avatar

Joined: Sun Sep 25, 2005 10:16
Posts: 7986
Location: Moved to London
hjeg2 wrote:
But how do you know that these 'bias on selection' factors aren't actually responsible for part of the general downward trend? In other words that they aren't already in effect included?

Because I’ve read the study and the report, it wasn’t mentioned in any shape or form.

Moreover, the analysis is a quantative one; no such figures exists for the effects of ‘bias on selection’ hence no inclusion in the report is possible. Feel free to look for yourself.

hjeg2 wrote:
It was just a gut feeling.

Forgive me if I seem to be putting words into your mouth, but have you based your claim of 'they are much better than nothing' on nothing more than a gut feeling? (as well as perhaps a misleading article written by Monbiot)

hjeg2 wrote:
but the study that Smeggy is quoting shows that speed cameras do affect what has happened in the past history.

Yes the study shows it, but I’ve already explained to you have the study is also flawed, in favour of cameras. I have already asked you a direct question on the issue, I await your response to that.

hjeg2 wrote:
As for the nice little business point, how about if, instead of being done for speeding when caught by a yellow speed camera, you get done for driving without due care and attention?

Cameras do not play a part in hazard recognition within the mental driving process because they are not a hazard (at least not directly). The subconscious will automatically filter them out, simply because they are static and away from the road. It is reasonable for drivers not to notice them, especially when there are real potential hazards ahead.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sat Dec 22, 2007 19:34 
Offline
User
User avatar

Joined: Sat Aug 13, 2005 23:28
Posts: 1940
hjeg2 wrote:
WildCat wrote:
Past history then has nothing to do with it. Ings had police lurkers long before Steviebabes upped periscope here. :popcorn: It just that the sites have history of revenue .,,, :popcorn:

Folk ain't as daft as the dumbed down Maths exams try to make them. :wink:


I've cut a load of the waffle out... :)

I have no idea what or who "Steviebabes" is,



:hehe:


He the local "Speedfinder General". I also call him the "Sub-marianted one" (he used to drive submarines when he was in Navy. :wink: - it alluding to this plus a tease to the daftness of his logic at times. (such as safer :yikes: to overtake on bend when justifying why scam on the healthy straight "straight" after the bend in question und not on its approach where it could be dangerous.


He called Steve C. We not see whisker to claw on speed cams :hehe: - but we agree on daft nonsense cycling lanes which undermine all safety issues anyway. :wink: He gave us a useful contact.. we getting somewhere at last on this one... but it difficult when you talking to some moron in "planning" who about as much use as the average chocolate teapot a the Mad Hatter's tea party. :popcorn:

Quote:

but the study that Smeggy is quoting shows that speed cameras do affect what has happened in the past history.

The study showed that speed cameras on average cut fatal and serious collisions by 10%. It's worth noting that that breaks down into 9% for mobile speed cameras and 17% for fixed cameras. A lesson here, perhaps?





Ach.. Pennington's "research" which got mixed reviews when appearing in BMJ. You now have to pay to view this now if you are not in the profession by the way :roll:

He did not really conclude anything und actually said this in one sentence in his piece because he found that there was no standard means of collating the data. Dr Mountain came across the same flaw too in her work. All he could conclude was that "based on what he was supplied with .. it would seem that the cams were "efficient" in what they were supposed to be doing. :popcorn: .. which not at all the same thing as presenting concrete hard evidence.

The reviews were mixed because it was "non research" in a way as it not based on a constant tangible of consistent data collection on the part of those operating these scams. Indeed they had no real history of the site before hand. Some of the scams were set up by the police as the road in question was a money spinner - with "discretion allowance even" A666 in Kearsley seem to be case in point. In-laws in Manchester say this lovely wide road und locals say "fave fine area" for police as far back as 60s. It has hereditary speed cam .. behind a bus shelter in front of some garage apparently ..

There are a number of these.. including Steve's most notorious ones. He not placed these at sites with KSI history.... but at sites with "easy revenue history". We live here longest time und people tell me things when I shop around the farm shoppes here. :wink:

Quote:

WildCat wrote:
But not saving anything like as claimed. Accidents have chance element in them.. set of particular circumstances which all combine.


I refer you to what I wrote above. Also, you will note that I try to avoid talking about "accidents", and instead talk about "collisions". There are what I would call genuine accidents and avoidable accidents.



If you COAST - you avoid many incidents. You also drive at safe speed at all times for the conditions which may be just above to just under .. but on average drive ..still compliant to lolly :wink:


But people still manipulate .. und the classic one was on Traffic Cops where unmarked just happened to be on road when dangerous twazak decide to drive like a w:censored:r


He drove at OTT speeds.. tailgating. cutting up.. but slowed to perfection past a Gatso before revving up again to OTT standards.

But for the happy co-incidence of un-marked police car.. which why I want more happy co-incidences of all types of police cars on the road as their presence make a difference to general standards of behaviour :wink:

It the COAST though - which help diffuse danger .. but chance always there just the same.

Quote:

WildCat wrote:
The criteria used for setting up a scam has been "loosely interpreted" without paying attention to actual common sense or worse with the idea of building up a nice little business. One single freak incident has met the required number of KSI at one fell swoop in many cases - which again skews up any chance of accurate measurement.


But how come there are so many of these "single freak incidents" then? We now have 6,000 (fixed?) speed cameras in place now don't we?



Cars carry people. If 4 people in one car in one single car incident are KSI .. then this count in the stats. Lots of people have passengers in their cars. That where the car score over bicycle und motorbike :wink: in terms of practicality of transporting family/pals.

Also - lot of bending of rules under the 15% minor incident clause in the guidelines too.. und these are guidelines for good practice und thus prone to manipulation.

Besdes as Pennington prove in his peer reviewed :wink: piece.. the way they collate data lead to skewing of stats to paint picture they want to paint .. which as "impressionist" as Monet's art und just as obscure as Picasso.. ..:popcorn:




Quote:
As for the nice little business point, how about if, instead of being done for speeding when caught by a yellow speed camera, you get done for driving without due care and attention?


That does not make as much money for them. :popcorn:

_________________
Nicht ganz im Lot!
Ich setze mich immer wieder in die Nesseln! Der Mad Doc ist mein Mann! Und ich benutzte seinen PC!

UND OUR SMILEYS? Smile ... und the the world smiles with you.
Smiley guy seen when you read
Fine me for Safe Speed
(& other good causes..)

Greatest love & Greatest Achievements Require Greatest Risk
But if you lose the driving plan - don't lose the COAST lesson.
Me?
Je ne regrette rien
!


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Dec 23, 2007 03:25 
Offline
Final Warning
Final Warning

Joined: Fri Oct 26, 2007 23:59
Posts: 280
WildCat wrote:
:hehe:

He the local "Speedfinder General". I also call him the "Sub-marianted one" (he used to drive submarines when he was in Navy. :wink: - it alluding to this plus a tease to the daftness of his logic at times. (such as safer :yikes: to overtake on bend when justifying why scam on the healthy straight "straight" after the bend in question und not on its approach where it could be dangerous.

He called Steve C. We not see whisker to claw on speed cams :hehe: - but we agree on daft nonsense cycling lanes which undermine all safety issues anyway. :wink: He gave us a useful contact.. we getting somewhere at last on this one... but it difficult when you talking to some moron in "planning" who about as much use as the average chocolate teapot a the Mad Hatter's tea party. :popcorn:

Quote:
but the study that Smeggy is quoting shows that speed cameras do affect what has happened in the past history.

The study showed that speed cameras on average cut fatal and serious collisions by 10%. It's worth noting that that breaks down into 9% for mobile speed cameras and 17% for fixed cameras. A lesson here, perhaps?


Ach.. Pennington's "research" which got mixed reviews when appearing in BMJ. You now have to pay to view this now if you are not in the profession by the way :roll:


No, this was the National Safety Camera Partnership study I think.

_________________
Before you moan about middle-lane hoggers, check that you yourself are obeying all the rules of the road.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Dec 23, 2007 03:50 
Offline
Final Warning
Final Warning

Joined: Fri Oct 26, 2007 23:59
Posts: 280
smeggy wrote:
hjeg2 wrote:
As we now know, the figures that I was talking about were the ones in George Monbiot’s article. The “original DfT figure” was something like a fall of 35% in KSIs attributed to speed cameras. When talking about RTTM like this there is/was an implication, even if you didn’t mean it, that RTTM is the sole cause of this fall – this is why I said above that “RTTM isn’t the case”.

I’ve shown Monbiot’s article to be misleading (as well as based on erroneous claims).


Well hold on, it's one or the other, as I was only dealing with the one claim in it, the 19% claim.

smeggy wrote:
hjeg2 wrote:
No-one is arguing that RTTM doesn’t exist. Coming out with the above just shows how Robin is either confused or is, as usual, trying to engineer an argument with me. The point is whether RTTM is responsible just by itself for the reduction of collisions after a speed camera has been installed. [Have patience; I shall come back to this.]

No it isn’t, it never was. The actual point is why you believe speed cameras are "much better than nothing", especially given the significance of RTTM, the long-term trend and the unaccounted effects of ‘bias on selection’.


Because, without knowing (if there are any) the unaccounted effects of 'bias on selection', speed cameras are responsible for (up to) a 10% reduction in FSCs, which includes 17% for fixed speed cameras, which are the type that I normally think of when I think of speed cameras.

smeggy wrote:
I have not decided any such claim. I repeat from much earlier in our discussion: "so leaving 1/3 to 1/4 of the claimed reduction seemingly genuinely attributable to speed cameras. However, the resultant 'genuine reduction' did not take into account 'bias on selection'. ". Perhaps you simply missed it or forgot it?


I must have missed it.

smeggy wrote:
hjeg2 wrote:
Smeggy, I never try to misrepresent anyone.

OK I’ll take your word for that, but that doesn’t mean you haven’t inadvertently succeeded.


And it would be different for you because...?

smeggy wrote:
hjeg2 wrote:
Yes, now that I know that, it certainly would be good to conduct research into what difference other measures make, but until then, I really don’t see how you can claim that speed cameras have no effect when you simply can’t say for sure.


Let’s be clear that I have made no such claim. My actual words (in full) were: "Given RTTM, 'bias on selection' and the accident stats, it is hard to understand how they can be of any significant benefit at all. Couple that with the negative side effects and you have to wonder if they really are better than nothing, let alone much better. ". As you can see, no such claim was put forward.


Is "you have to wonder" so different from "no effect"? Do you think that speed cameras have an effect? If so, what effect?

smeggy wrote:
hjeg2 wrote:
Except that I’ve told you that the A3 is a three-laned road. There aren’t any extra traffic calming features. There hasn’t been, to the best of my knowledge, any local road safety awareness courses. What else could there have been?

An awareness campaign need not be limited to local road safety courses. Drivers knowing that there was a serious accident in an area may prompt them to drive more cautiously in that area. There are usually signs installed following such accidents asking for witnesses of such events.


How many drivers would have known that there had been a serious accident? And I really doubt there would have been any signs installed on a three-lane dual carriageway.

smeggy wrote:
hjeg2 wrote:
smeggy wrote:
I said that in response to you saying that it "will" play a part. I asked you to justify the "will" in your statement. I presume anything of relevance still won’t be forthcoming.

No of course it won’t be; as I said before, I just assumed that that would be one of the things that you would say had played a part. I was saying it so that you didn’t have to. Your negativity really is completely unfounded here.

In short: you cannot substantiate your comment. I think we can leave it at that.


Well considering that I said "no of course it won't be", I really don't know why you bothered to say the above. Unless of course you hated the idea that a lower speed limit had played any part in reducing the number of serious collisions, and you wanted to ram the point home. Which of course means that if there has been a reduction above and beyond RTM then it was in fact the speed cameras that were the cause.

smeggy wrote:
Given that the best study on the subject has shown that 10% (absolute) of the KSI fall is due to speed cameras, but that ‘bias on selection’ exists and was unaccounted for, do you agree that the 10% figure must also be optimistic and that the figure could (probability aside) actually be 0%, or even negative? If not then why not?


Sure it could be 0%. But I don't accept that the 10% figure "must" be optimistic. Also, it's interesting and worth noting that whilst mobile speed cameras are attributed with a 9% drop in FSCs, fixed cameras were attributed with a 17% drop.

_________________
Before you moan about middle-lane hoggers, check that you yourself are obeying all the rules of the road.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Dec 23, 2007 08:54 
Offline
User

Joined: Sun Sep 03, 2006 04:10
Posts: 3244
All-in all, we can agree that we don't agree ?
I don't agree with the camera partnerships figures, in many cases they ignore reality.
In any case, they need to enlist some statisticians that understand statistics.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Dec 23, 2007 15:23 
Offline
Friend of Safe Speed
Friend of Safe Speed
User avatar

Joined: Sun Sep 25, 2005 10:16
Posts: 7986
Location: Moved to London
hjeg2 wrote:
Well hold on, it's one or the other, as I was only dealing with the one claim in it, the 19% claim.

It’s both, as one was based upon the other, the original being flawed (erroneously included long-term trend).

hjeg2 wrote:
And it would be different for you because...?

Because I have demonstrated instances of misrepresentation (accidental or otherwise); you even accept that I was correct with one of them (the one you missed).

hjeg2 wrote:
Is "you have to wonder" so different from "no effect"? Do you think that speed cameras have an effect? If so, what effect?

Yes it is different, I made no definitive claim as to the significance of a characteristic, you did (which is what prompted our discussion – “they are much better than nothing.”).

www.safespeed.org.uk/sideeffects.pdf

hjeg2 wrote:
How many drivers would have known that there had been a serious accident? And I really doubt there would have been any signs installed on a three-lane dual carriageway.

Why do you say that?
To answer yours: drivers who drove past the accident (other carriageway too), saw the appeal signs (if applicable), listened to the radio reports or local TV news.

hjeg2 wrote:
Which of course means that if there has been a reduction above and beyond RTM then it was in fact the speed cameras that were the cause.

Of course not. What have we been discussing for the last 6 pages?

hjeg2 wrote:
Because, without knowing (if there are any) the unaccounted effects of 'bias on selection', speed cameras are responsible for (up to) a 10% reduction in FSCs, which includes 17% for fixed speed cameras, which are the type that I normally think of when I think of speed cameras

Sure it could be 0%. But I don't accept that the 10% figure "must" be optimistic.

Why not? We’ve already discussed (dare I say agree) that speed cameras in general result with a 10% drop. The study and report made no reference to the bias on selection effects already discussed; hence this is inherently contained within the overall figure (unless you can dispute it). So how can you not accept that the 10% must be optimistic – unless you are claiming that the bias on selection effect could have an average contribution of 0 ? Would claiming so be a bit far fetched? (especially given what I’ve just discovered below)

Seperately: would you agree that it is wrong the SCPs/government to tout even the 10% figure because it poses a real risk of being optimistic and that their study/report must be reviewed?

hjeg2 wrote:
Also, it's interesting and worth noting that whilst mobile speed cameras are attributed with a 9% drop in FSCs, fixed cameras were attributed with a 17% drop.

I am so glad you brought this up. In digging further, I found something that strongly supports my original argument, something that I had previously overlooked.

Where did the 17% figure come from? A quick Google indicates there are 5000 fixed sites and about 3000 possible mobile sites in the UK. How a large weighting of 17% summed with a smaller weighting of 9% results with an overall weighting of 10% is beyond me...

... unless you were being as selective with your figures as PA Consulting Group - so making my argument of ‘bias on selection’ greatly more significant than previously discussed (and making your A3 example less significant). Can you see what it is?


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Dec 23, 2007 18:55 
Offline
User
User avatar

Joined: Mon Mar 08, 2004 21:41
Posts: 3608
Location: North West
hjeg2 wrote:
smeggy wrote:
hjeg2 wrote:
As we now know, the figures that I was talking about were the ones in George Monbiot’s article. The “original DfT figure” was something like a fall of 35% in KSIs attributed to speed cameras. When talking about RTTM like this there is/was an implication, even if you didn’t mean it, that RTTM is the sole cause of this fall – this is why I said above that “RTTM isn’t the case”.

I’ve shown Monbiot’s article to be misleading (as well as based on erroneous claims).


Well hold on, it's one or the other, as I was only dealing with the one claim in it, the 19% claim.



Oh Mongiblet's pieces (all of them) more or less revolve around the gov stats (which have never been "peer reviewed". Subject to the audit commission though.. who recommended changes to various practices :popcorn:


Quote:


smeggy wrote:
hjeg2 wrote:
No-one is arguing that RTTM doesn’t exist. Coming out with the above just shows how Robin is either confused or is, as usual, trying to engineer an argument with me. The point is whether RTTM is responsible just by itself for the reduction of collisions after a speed camera has been installed. [Have patience; I shall come back to this.]

No it isn’t, it never was. The actual point is why you believe speed cameras are "much better than nothing", especially given the significance of RTTM, the long-term trend and the unaccounted effects of ‘bias on selection’.


Because, without knowing (if there are any) the unaccounted effects of 'bias on selection', speed cameras are responsible for (up to) a 10% reduction in FSCs, which includes 17% for fixed speed cameras, which are the type that I normally think of when I think of speed cameras.




But you have not really answered the question as to why you think they are better than nothing - without relying on some data which has not really been proven to absolute - given that this same data includes the type of incident which Kevin Delaney recounted on R4 and which my wife referred to.. the one which takes out 4 in one car and this provides the criteria for a speed cam.


(Delaney set up the first ever cam and now has some grave doubts over the way these cams have replaced real road safety practices .. the ones which were tested and true. By this I mean the fact that the Green Cross Code Man and Tufty have published stats from their campaign which showed the child pedestrian rate fall rapidly. Mind you .. :hehe: Darth Vader could not get away with calling a child - stepping out in front of a car a stupid muppet these days. :hehe: And I do not suppose the one about the playing near a railway - ending with a really sarcastic voice about how stupid the boy who died was - would be allowed today. You did not see him die.. but you knew he had. I was about 5 when this was on the TV. I still recall that stern voice in the advert ..and I think this also made little boys think twice about playing near rail tracks - which seemed to kill a lot of kids around that time. I do recall a boy at school dying on a railtrack. Not playing chicken .. but logging train numbers. That was a hobby back then. , in the age of steam and diesels sharing the railways.

Also Jimmy Fix It Saville's Clunk Click campaign also saved countless lives and is just as valid today.

But there are stats to show these campaigns were very effective

However, these were drawn up from proper police and hospital records to a standard and could thus be regarded as reasonably reliable.

The cam data? No one has anything standard. I will have to send Claire or Peter or Roger the few results which Lancs eventually parted with. I cannot get Steve to reply likewise. I wish he would as any data better than none and a fail to reply just makes one .. well.. suspicious.

But back to Lancs. They have one cam which we always thought well placed really. At the start .. it pinged like mad. Now it's a low earner as they re-engineered the road in question. Unusually for Lancs.. this cam in the Blackburn area did not involve a reduced limit.. but some paint work and better and yet uncluttered road signage.


Lancs are honest to admit that the road engineering did negate the need for the cam in question and it rarely houses a camera these days.

We have another three which are definitely "dodgy" as Lancs revealed they had no pre-cam incident data ,. but could confirm no incident occurred since the cams appeared. These cams show a more than positive "efficiency stat" on their website.. but they are nor measuring anything or comparing anything .........so this throws up a big question as to why they were erected or how one can claim 80% success on this basis

Lancs though made use of the 15% "get out clause" and included minor scrapes/no injury per the data we did receive. I think Willi passed it up to Paul. It's recent and might just be in the stuff he never got around to sorting.

I knew he was ill.. more seriously so than he let on. I phoned about 3 weeks before.. he sounded "tired to point of fatigued to my ears. I knew he was awaiting surgery and why. But he was so dedicated to his cause.


Oh and hjeg2..

We are a polite bunch on here and no one is insulting you.. just perhaps disagreeing with your point of view or meeting half way at times

but.. riding a bicycle would not have helped Paul that much in his condition. Please convey this to your cycling mates. I am a doctor and whilst I specialise in virology .. I do have some knowledge of cardiology in so far as when a virus affects the heart .. requiring a new one.

But lurgies .. lack of exercise (and I understand Paul Smith enjoyed a walk all the same so you cannot level this at him either ) are one thing // but .. with the best will in the world.. stress and circumstance take their toll and I only wish I'd donated more to his fund now.



Quote:

smeggy wrote:
hjeg2 wrote:
Except that I’ve told you that the A3 is a three-laned road. There aren’t any extra traffic calming features. There hasn’t been, to the best of my knowledge, any local road safety awareness courses. What else could there have been?

An awareness campaign need not be limited to local road safety courses. Drivers knowing that there was a serious accident in an area may prompt them to drive more cautiously in that area. There are usually signs installed following such accidents asking for witnesses of such events.


How many drivers would have known that there had been a serious accident? And I really doubt there would have been any signs installed on a three-lane dual carriageway.




We have incidents on M network around here. There are always signs appealing for witnesses.. the last ones being for the J-walkers on Mgi and M60 :popcorn:

It's routine. :popcorn:

Quote:
smeggy wrote:
hjeg2 wrote:
smeggy wrote:
I said that in response to you saying that it "will" play a part. I asked you to justify the "will" in your statement. I presume anything of relevance still won’t be forthcoming.

No of course it won’t be; as I said before, I just assumed that that would be one of the things that you would say had played a part. I was saying it so that you didn’t have to. Your negativity really is completely unfounded here.

In short: you cannot substantiate your comment. I think we can leave it at that.


Well considering that I said "no of course it won't be", I really don't know why you bothered to say the above. Unless of course you hated the idea that a lower speed limit had played any part in reducing the number of serious collisions, and you wanted to ram the point home. Which of course means that if there has been a reduction above and beyond RTM then it was in fact the speed cameras that were the cause.


Reducing the limit and re-engineering may have reduced the incidents. You cannot claim the speed cam had any influence here because it is monitoring a completely different road condition :popcorn:

Had the incidents continued after reducing a speed limit.. then we have KSI history of road at that speed limit.

But it seems to me that they reduced the limit and set up the scam to enforce without seeing how far the lowered limit changed the situation.

You have not proven that the cam works.. only that it enforces a new limit which can still kill all the same :popcorn:

Quote:

smeggy wrote:
Given that the best study on the subject has shown that 10% (absolute) of the KSI fall is due to speed cameras, but that ‘bias on selection’ exists and was unaccounted for, do you agree that the 10% figure must also be optimistic and that the figure could (probability aside) actually be 0%, or even negative? If not then why not?


Sure it could be 0%. But I don't accept that the 10% figure "must" be optimistic. Also, it's interesting and worth noting that whilst mobile speed cameras are attributed with a 9% drop in FSCs, fixed cameras were attributed with a 17% drop.


You still are only quoting the dogma served ,, which has never been peer reviewed. I mention this as this seems ever so important to some... and it means nowt in the real world out there really :popcorn:

_________________
If you want to get to heaven - you have to raise a little hell!

Smilies are contagious
They are just like the flu
We use our smilies on YOU today
Now Good Causes are smiling too!

KEEP SMILING
It makes folk wonder just what you REALLY got up to last night!

Smily to penny.. penny to pound
safespeed prospers-smiles all round! !

But the real message? SMILE.. GO ON ! DO IT! and the world will smile with you!
Enjoy life! You only have the one bite at it.


Top
 Profile Send private message  
 
 Post subject:
PostPosted: Sun Dec 23, 2007 22:32 
Offline
Final Warning
Final Warning

Joined: Fri Oct 26, 2007 23:59
Posts: 280

Mad Moggie wrote:
I knew he was ill.. more seriously so than he let on. I phoned about 3 weeks before.. he sounded "tired to point of fatigued to my ears. I knew he was awaiting surgery and why. But he was so dedicated to his cause.


I don't know why you're telling me this.

Mad Moggie wrote:
Oh and hjeg2..

We are a polite bunch on here and no one is insulting you.. just perhaps disagreeing with your point of view or meeting half way at times


I don't know specifically what you're referring to here, but I consider being called a kid an insult, as well as, I believe, having it suggested that I am blind and stupid. The point here is that they are ad hominems which I have been warned about.

Mad Moggie wrote:
but.. riding a bicycle would not have helped Paul that much in his condition.


Er, I never said it would have!

Mad Moggie wrote:
Please convey this to your cycling mates.


I really do hate it when people make random asumptions. What cycling mates?

Mad Moggie wrote:
But lurgies .. lack of exercise (and I understand Paul Smith enjoyed a walk all the same so you cannot level this at him either )


Er, I'm not.



Any other random assumptions you wish to make?

_________________
Before you moan about middle-lane hoggers, check that you yourself are obeying all the rules of the road.


Top
 Profile Send private message  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 123 posts ]  Go to page Previous  1, 2, 3, 4, 5, 6, 7  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: Bing [Bot] and 44 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You can post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group
[ Time : 0.146s | 12 Queries | GZIP : Off ]