The effects of imposing speed limits
Discussion
On January 1st 2007 the Northern Territory in Australia imposed open road speed limits. As most will be aware the NT had unrestricted roads until of course the Territory government (Labour natch) decided that speed limits were the answer to the road toll. What the research showed was that most accidents up in NT were caused by alcohol, tourists on dirt roads; pretty much everything other than speed in fact. So naturally, if speed is not the prime cause of accidents and you are a politician or a bureaucrat what do you do? Correct, impose speed limits.
Anyway, one year on and the NT has announced the success of this policy via the road toll statistics and the percentage reduction is? Well actually it's a 20% increase.
Anyway, one year on and the NT has announced the success of this policy via the road toll statistics and the percentage reduction is? Well actually it's a 20% increase.
80Bob said:
On January 1st 2007 the Northern Territory in Australia imposed open road speed limits. As most will be aware the NT had unrestricted roads until of course the Territory government (Labour natch) decided that speed limits were the answer to the road toll. What the research showed was that most accidents up in NT were caused by alcohol...
Hence my favourite road sign from across there "If you drink and drive, you're a Bloody idiot"80Bob said:
...tourists on dirt roads...
True enough. Been there, done it, got the T-shirt.80Bob said:
...pretty much everything other than speed in fact. So naturally, if speed is not the prime cause of accidents and you are a politician or a bureaucrat what do you do? Correct, impose speed limits....
This is probably more to do with the NT being a world unto itself, not even recognised as part of Australia by the majority of Australians!!!80Bob said:
Anyway, one year on and the NT has announced the success of this policy via the road toll statistics and the percentage reduction is? Well actually it's a 20% increase.
Increase in what? Deaths. Injury. Collisions. Also, what are the actual numbers (you can't tell everything from a percentage as you know).BFF
80Bob said:
On January 1st 2007 the Northern Territory in Australia imposed open road speed limits. As most will be aware the NT had unrestricted roads until of course the Territory government (Labour natch) decided that speed limits were the answer to the road toll. What the research showed was that most accidents up in NT were caused by alcohol, tourists on dirt roads; pretty much everything other than speed in fact. So naturally, if speed is not the prime cause of accidents and you are a politician or a bureaucrat what do you do? Correct, impose speed limits.
Anyway, one year on and the NT has announced the success of this policy via the road toll statistics and the percentage reduction is? Well actually it's a 20% increase.
i'll really must dig out some very old magazines ive got in the loft. including articles by Sir Stirling Moss arguing against the 'new' 70limit over here & his extremley sensible reasons against it.Anyway, one year on and the NT has announced the success of this policy via the road toll statistics and the percentage reduction is? Well actually it's a 20% increase.
Im pretty sure that other articles in there say how much more dangerous the motorways seem since the limit due to traffic bunching. plus i seem to remember that while the 70limit was in its 3months trial accidents when UP by about one third.
time & time its proved limits outside urban areas are NOT the answer, yet do the prats in charge listen? of course they dont.
These are an increase in fatalities in the NT over the 12 months. The increase was from 44 to 57 which in actual fact looks like 29% to me (although my maths may be a bit ropey). There are now calls for the limits to be scrapped.
A brief link;
http://www.caradvice.com.au/9009/opposition-nt-spe...
A brief link;
http://www.caradvice.com.au/9009/opposition-nt-spe...
Sorry, Von but 57 minus 44 is not 5. Not sure where you got that number from?
The history is that the roads where the most fatalities were occurring pre the limits were on roads with limits already (in urban areas) and the main problems were alchohol related and loss of control on unsealed (gravel) roads. The unrestricted sections were not the problem but this was a typical knee jerk reaction by the politicians.
The history is that the roads where the most fatalities were occurring pre the limits were on roads with limits already (in urban areas) and the main problems were alchohol related and loss of control on unsealed (gravel) roads. The unrestricted sections were not the problem but this was a typical knee jerk reaction by the politicians.
What was the year on year variation like prior to the enforcement of a speed limit? We have to be careful not to fall into the same regression to the mean trap that the SCPs do. I suspect that there was a +/- variation of about 10% (very small data set) anyway. What this means is that it makes no difference whether there is an enforced speed limit or not. The real killer statistic would be what the average speed was along these roads after the introduction of the speed limit. If the average speed dropped by a significant amount yet the number of deaths failed to get outside the (probably) massive standard error, then you have a pretty strong argument that effective enforcement of speed limits has little or no effect.
Otherwise, basing anything on this observation is no better than the disingenuous nonsense the camera partnerships vomit forth from time to time.
Otherwise, basing anything on this observation is no better than the disingenuous nonsense the camera partnerships vomit forth from time to time.
fluffnik said:
Cpn Jack Spanner said:
So, it proves (once again) that anyone who imposes or enforces speed limits is partially responsible for the deaths of innocent people, and must live with the consequences of their actions.
...Nothing new.
They should be jailed for manslaughter....Nothing new.
If the SCP reacted to data in this way everyone would condemn them. Why are you so willing to support what you say you disagree with (rhetorical question, as I think I know why).
BFF
Big Fat F'r said:
fluffnik said:
Cpn Jack Spanner said:
So, it proves (once again) that anyone who imposes or enforces speed limits is partially responsible for the deaths of innocent people, and must live with the consequences of their actions.
...Nothing new.
They should be jailed for manslaughter....Nothing new.
If the SCP reacted to data in this way everyone would condemn them. Why are you so willing to support what you say you disagree with (rhetorical question, as I think I know why).
BFF
So there are 2 possibilities for the increase:
1. Statistically insignificant natural variation
2. Statistically significant upward movement
Either of these is difficult for the partnership to swallow because it means at best that cameras have had a neutral effect.
Peter Ward said:
Big Fat F'r said:
fluffnik said:
Cpn Jack Spanner said:
So, it proves (once again) that anyone who imposes or enforces speed limits is partially responsible for the deaths of innocent people, and must live with the consequences of their actions.
...Nothing new.
They should be jailed for manslaughter....Nothing new.
If the SCP reacted to data in this way everyone would condemn them. Why are you so willing to support what you say you disagree with (rhetorical question, as I think I know why).
BFF
So there are 2 possibilities for the increase:
1. Statistically insignificant natural variation
2. Statistically significant upward movement
Either of these is difficult for the partnership to swallow because it means at best that cameras have had a neutral effect.
Without more data you cannot say that at best they have had a neutral effect, as you don’t know there has been no change. Just like they cannot say it has been an improvement, as there is not enough data provided to show any.
Both sides are wrong to argue their passionately held beliefs based only on very small data sets.
So lets get all the data, agree it is an acceptable amount, then study it properly, not this subjective “ye is all murderers” crap.
BFF
80Bob said:
Sorry, Von but 57 minus 44 is not 5. Not sure where you got that number from?
The history is that the roads where the most fatalities were occurring pre the limits were on roads with limits already (in urban areas) and the main problems were alchohol related and loss of control on unsealed (gravel) roads. The unrestricted sections were not the problem but this was a typical knee jerk reaction by the politicians.
I didn't use a journalist's figures, I got that latest figures released (14/12/07 & released monthly) from the Australian government's transport safety bureau. The history is that the roads where the most fatalities were occurring pre the limits were on roads with limits already (in urban areas) and the main problems were alchohol related and loss of control on unsealed (gravel) roads. The unrestricted sections were not the problem but this was a typical knee jerk reaction by the politicians.
It doesn't break down on which roads the fatalities happened, that's why I asked if there was an increase or decrease in fatalities on the newly limited roads.
Edited by vonhosen on Monday 7th January 17:45
Er, I think you'll find that that Brunstrom chap takes all the credit for a reduction in road deaths, I don't see why there should be any other conclusion when the same statistics point the other way. Speed limits in one area reduce deaths, speed limits in another increase deaths. QED.
However . . . the speed limit thing is something we've lived with for 40 years, both those that enforce and those that are enforced live in an institutonalised system where no-one can do any wrong if they stay under the limit (or that is the perception). And those that exceed the limits dive around sections of road where they think they can get away with it, rather than keep a steady speed for a whole journey, and the enevitable happens - mistakes are made. Direct cause: bad speed limits.
It's an easy case to prove, for either side. Pick a large county in England, look at the statistics for a place that has been under the thumb of 40 years of limits and the long term effects on the mental perspective of the driving citizens, then pick a similar sized chunk of the Isle of Man, where there are no speed limits and people make their own pace on the roads based on their own personal opinion of their and their cars abilities.
This would be the clearest comparison of like for like. (who knows - England may be safer!) Anyone know where to find out?
However . . . the speed limit thing is something we've lived with for 40 years, both those that enforce and those that are enforced live in an institutonalised system where no-one can do any wrong if they stay under the limit (or that is the perception). And those that exceed the limits dive around sections of road where they think they can get away with it, rather than keep a steady speed for a whole journey, and the enevitable happens - mistakes are made. Direct cause: bad speed limits.
It's an easy case to prove, for either side. Pick a large county in England, look at the statistics for a place that has been under the thumb of 40 years of limits and the long term effects on the mental perspective of the driving citizens, then pick a similar sized chunk of the Isle of Man, where there are no speed limits and people make their own pace on the roads based on their own personal opinion of their and their cars abilities.
This would be the clearest comparison of like for like. (who knows - England may be safer!) Anyone know where to find out?
Edited by Cpn Jack Spanner on Monday 7th January 21:49
Cpn Jack Spanner said:
Er, I think you'll find that that Brunstrom chap takes all the credit for a reduction in road deaths, I don't see why there should be any other conclusion when the same statistics point the other way. Speed limits in one area reduce deaths, speed limits in another increase deaths. QED.
However . . . the speed limit thing is something we've lived with for 40 years, both those that enforce and those that are enforced live in an institutonalised system where no-one can do any wrong if they stay under the limit (or that is the perception). And those that exceed the limits dive around sections of road where they think they can get away with it, rather than keep a steady speed for a whole journey, and the enevitable happens - mistakes are made. Direct cause: bad speed limits.
It's an easy case to prove, for either side. Pick a large county in England, look at the statistics for a place that has been under the thumb of 40 years of limits and the long term effects on the mental perspective of the driving citizens, then pick a similar sized chunk of the Isle of Man, where there are no speed limits and people make their own pace on the roads based on their own personal opinion of their and their cars abilities.
This would be the clearest comparison of like for like. (who knows - England may be safer!) Anyone know where to find out?
Why do you need speed limits in town if you truly trust the judgement of drivers to choose appropriate speeds for circumstances ?However . . . the speed limit thing is something we've lived with for 40 years, both those that enforce and those that are enforced live in an institutonalised system where no-one can do any wrong if they stay under the limit (or that is the perception). And those that exceed the limits dive around sections of road where they think they can get away with it, rather than keep a steady speed for a whole journey, and the enevitable happens - mistakes are made. Direct cause: bad speed limits.
It's an easy case to prove, for either side. Pick a large county in England, look at the statistics for a place that has been under the thumb of 40 years of limits and the long term effects on the mental perspective of the driving citizens, then pick a similar sized chunk of the Isle of Man, where there are no speed limits and people make their own pace on the roads based on their own personal opinion of their and their cars abilities.
This would be the clearest comparison of like for like. (who knows - England may be safer!) Anyone know where to find out?
Edited by Cpn Jack Spanner on Monday 7th January 21:49
Edited by vonhosen on Monday 7th January 21:55
vonhosen said:
It doesn't break down on which roads the fatalities happened, that's why I asked if there was an increase or decrease in fatalities on the newly limited roads.
i don't know the type of roads being discussed either but looking at such small data sets and such a small number of incidences I would hazard a guess that the existence of a speed limit on these roads has no effect on the natural variation year on year. 10, 15, 20% changes in casualties sounds like a lot, until you realise that that could be accounted for by a single multiple occupancy incident. At best speed limit enforcement, in this case, has failed to move the casualties figures significantly (the SEM of such a small data set is going to be massive) in either direction, at worst it has increased the numbers. Edited by vonhosen on Monday 7th January 17:45
Of course without a more complete data set over a number of years its impossible to draw any meaningful conclusions either way.
Cpn Jack Spanner said:
Er, I think you'll find that that Brunstrom chap takes all the credit for a reduction in road deaths, I don't see why there should be any other conclusion when the same statistics point the other way. Speed limits in one area reduce deaths, speed limits in another increase deaths. QED.
There is not enough data to say anything about the introduction of limits in this particular case. You can't say there was a good change, you can't say there was a bad change, and you can't even say there has been no change.What you need is as much data as possible, collected on the roads where the cameras were introduced, before and after the change. Conclusions based on anything else are pure smokescreens, used to highlight an individuals personal bias (whichever side they are on).
What we should be pushing for on here is rational analysis (which may lead to genuine changes) not emotive junk (which only serves to extend the membership of websites, and increase the sales of newspapers).
Perhaps the most revealing comment is the one from the spokesperson who said that she was worried about this attack on their (NT) way of life. Methinks therein lies the real problem.
BFF
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