Speed Cameras Increase Freeway Accidents 31-55%
from the shhhhhhhh dept
Bob Dole writes “Illinois readers should pay special attention to an official newly-uncovered study that the UK government never wanted you to see. It shows that injury accidents increased 31 percent when speed cameras were used on freeways, and they increased 55 percent when used in freeway work zones. When the researchers who were commissioned to study the effects of cameras in construction zones came up with these results, the UK government did everything in its power to prevent the data from ever seeing the light of day. After all, they make about 700 million pounds (a billion US dollars) yearly from the machines. Illinois is about to implement its own work zone speed camera program, “to reduce accidents and save lives.” I’m sure the last thing on the mind of Illinois bureaucrats is all the $375 first offense, $1000 second offense citations it will generate.” Update: Some good points in the comments ripping this study apart. It is worth noting, by the way, that the source of it, TheNewspaper, is based on the idea of stopping redlight and speed cameras. It sounds like they’re misquoting this study and misreading it on purpose.
Comments on “Speed Cameras Increase Freeway Accidents 31-55%”
Say NO to Speed Cameras
I remember when we had photo radar in Ontario a while back. Everytime there was a van or van-looking vehicle parked at the side of the road, a sea of red brake lights would appear, as everyone braked to slow down. There were a few near misses. I always wondered how that made driving safer. Raise the speed limits to the 85th percentile and accidents will fall.
No Subject Given
A few years back Arkansas tore up I-40 and repaved it. I have to give them credit that they did the best job of maintaining traffic flow I’ve ever seen. About five miles before the construction zone were signs posted saying “RIGHT LANE CLOSED 5 MILES” and so on until at one mile it was “MERGE NOW” and then “NO PASSING.” Traffic usually flowed at a pretty steady rate through the construction zones. One afternoon some bozo tried to cut through the no passing zone and cut in at the convergence of orange cones right behind me. Then Kaboom! The semi directly behind me just rammed him out of the way and into the orange cones. I’d hate to have to explain that to my insurance company. Or the state troopers. And yes he was yakking on a cell phone the whole time.
Please Check Your Facts
If you look at the study (PDF: http://www.thenewspaper.com/rlc/docs/04-trl595.pdf) you will see that it actually shows no increase in accidents as a result of speed cameras, and a 1% decrease in serious accidents. The 31-55% increase quoted is either the result of extremely bad math, or perhaps the group that created the press release containing these inaccuracies (http://www.safespeed.org.uk/) fudged the figures on purpose.
There is also a serious mis-quote in the article.
“”sites with speed camera enforcement had a significantly higher without works ratio than sites that did not use camera enforcement”
became
“non-works [personal injury accident] rate is significantly higher for the sites with speed cameras than the rate for sites without.”
Obviously someone is bending this study to their own ends, and betting that people will reprint it without checking their facts.
Re: Please Check Your Facts
> The 31-55% increase quoted is either the result of extremely bad math, or perhaps the group that created the press release containing these inaccuracies (http://www.safespeed.org.uk/) fudged the figures on purpose.
If you’ve seen SafeSpeed/Paul Smith before, you’ll know the obvious answer is “both of the above”.
This piece of 'news' is rubbish
This techdirt article, and the “theNewspaper.com” article, are incorrect.
“[The UK study] shows that injury accidents increased 31 percent when speed cameras were used on freeways,…”
No it doesn’t. Read the report. All the accidents that make up this 31% happened over three preceding years, BEFORE any cameras were installed.
(Does the techdirt author believe these speed cameras somehow went back in time and injured people? Sheesh!)
The “31%” actually shows that road engineers chose to deploy analogue speed cameras on the more dangerous sections of freeway. On average, the sections chosen were _already_ 31% more dangerous. That’s probably why they were chosen.
“… and they increased 55 percent when used in freeway work zones.”
Also rubbish, for the same reason. Cameras were used on sites that were already known to be 31% more dangerous, even under normal conditions. Yes, there was an 18% accident rate increase when the road works began on these busy sections. But no, you can’t blame the cameras for that. And you certainly can’t mutliply-in the 31% from before the cameras were even there! (55% is 31% compounded with 18%, or equivalently 1.31 x 1.18 = 1.55).
Re: This piece of 'news' is rubbish
RK:Thanks for reading the article closely, I tried but it turned out to be a bit of a beast for which I didn’t have time to do it justice.
As an anecdote, the Flying Spaghetti Monster website (http://www.venganza.org/) states that:
“You may be interested to know that global warming, earthquakes, hurricanes, and other natural disasters are a direct effect of the shrinking numbers of Pirates since the 1800s(…)As you can see, there is a statistically significant inverse relationship between pirates and global temperature.”
I also heard that something like 90% of child molesters have milk in their fridge, suggesting a direct causal link between milk ingestion and perverse behavior.
Kind of sounds like that is the logic that concludes that the addition of traffic cameras at otherwise dangerous freeway sites is the obvious cause of any accidents that may occur there.
Re: This piece of 'news' is rubbish
Safespeed Explanation
Kudos to previous posters
“The study showed that there was no significant difference in the rate of PIAs [Personal Injury Accidents] when road works were present on the motorway … No significant difference was observed in the PIA rate for sites with and without speed cameras. However there was a 1% decrease in the proportion of Fatal and Serious PIAs recorded at the sites with speed cameras” PDF
speed cameras
Mike, I suggest you start being a little more critical of Bob Dole’s contributions. Anyone who reads Techdirt regularly already knows what he thinks about speed cameras: he doesn’t like them. If you see “Bob Dole” at the top of a post, it means without fail that it will be about some study or news story relating how terrible speed cameras are. Fine, great — message received, speed cameras are evil, we get it already. And if this latest bit of misinformation is typical of Bob’s contributions, he doesn’t deserve the soapbox that Techdirt supplies him.
Re: speed cameras
If there are MORE accidents with speed cameras (that make drivers slow down), then there is a flaw in the study (or statistics). Just use common sense…Why would a camera that looks for speeders make people SPEED UP”?? Hellooo???
Re: Re: speed cameras
What are you on about? Who said anything about making people speed up?
The problem is that slowing down does not necessarily mean less accidents. If traffic is forced to travel at a speed that is well below the 85th percentile, that section of roadway will have more accidents than a section where the speed is set at the 85th percentile.
Re: Re: Re: speed cameras
Mousky said “The problem is that slowing down does not necessarily mean less accidents. If traffic is forced to travel at a speed that is well below the 85th percentile, that section of roadway will have more accidents than a section where the speed is set at the 85th percentile”
Ahh..so going slower leads to more accidents than going faster. In that case the study does make sense. Thanks for clearing that up.
Re: Re: Re:2 speed cameras
Going slower than the 85th percentile typically leads to a greater speed differential between cars – you have more cars travelling over a greater speed range which usually means having to break for slower cars, more left lane bandits, and so on, leading to a greater probability of accidents.
You want as many cars as possible travelling over a narrow speed range – setting the speed limit at the 85th percentile achieves that goal. The use of speed cameras usually indicates that the speed limit has been set artifically too low.
Re: Re: Re:3 speed cameras
“The use of speed cameras usually indicates that the speed limit has been set artifically too low.”
This just boggles the mind.
So the “artificial” 40 km/h speed limit outside schools that’s set to stop people killing school children. It’s sometimes enforced by speed cameras and yet you’re blaming the speed cameras for any injury or fatality that occurs there?!?
The 50 km/h residential street speed limit, set to ensure that people have a higher chance of stopping when a kid runs out onto the road. Some of those streets happens to be straight. “hey, it’s straight, why can’t I travel as fast as my car will go?” Sometimes there are speed cameras to catch people speeding along the street. And you blame the speed camera?!?
I wish all you speed-camera blamers would just get a bloody grip on reality and learn to be responsible for your actions.
Re: Re: speed cameras
That assumes that faster speeds cause more accidents.
Why is it then that in the UK (where the original study came from) the roads with the highest speed limits (called ‘motorways’) have the lowest number of accidents?
Jeffj – if higher speeds automatically mean more accidents then good luck to you on your next airline flight….
Re: Re: Re: speed cameras
PS SteveC above is a member of a speed camera operating organisation that took its own forum down rather than answer the dozens of questions posted there from members of the public regarding their own published misuse of statistics, an example being CSCP trying to claim success by trumpeting a reduction in deaths on their roads over a 4 month period (Jan-Apr 2004) based on the same quarter the previous year.
The success claim stayed on their forum until the annual figures revealed an INCREASE in deaths in 2004 over the preceding 12 months.
SteveC claimed the information had ‘timed out’ and deleted itself automatically, yet when pressed about it one of his colleagues revealed that the information had indeed been deleted.
The outcry and criticism that followed led SteveC and his colleagues to withdraw the forum rather than face the music.
No Subject Given
Another note worth mentioning is that only two sites “with works” had traffic flow data available…. I wonder what the error in traffic flow is for those sites? Probably much higher than any of the small percentages of differences that were found (ignoring the larger percentages that speedsafe are touting, as others have pointed out they aren’t really valid).
I didn’t look at all the numbers in the report, and I don’t have time. Did anyone notice if the numbers are their at an individual site level? cause then I think they would be valid. Of course they either aren’t their, or don’t give the numbers that speedsafe wanted, otherwise they would hav used them.
If you ask me this survey is pretty useless (2 sample sites for accurate flow vs 24, hello?) even for the purpose of what it was really trying to do, let alone for determining the pros/cons of speed cameras.
But hey, any thing that helps get rid of them is ok by me 🙂
Re: No Subject Given
ooops, should have proof read:
Another note worth mentioning is that only two sites “with works” had traffic flow data available…. I wonder what the error in traffic flow is for those sites?
should read:
I wonder what the error in traffic flow is for the other sites? (ie those without available data)
Re: Re: Responding to the charges.
First, to the “misquote” charge, why don’t you look here: graphic. There’s a direct link to it in the article itself. Obviously the “defender” of cameras didn’t bother reading much. Aside from changing PIA into Personal Injury Accident, it’s verbatim.
Second, to the numbers. Again, READ the chart.
Works accidents with speed cameras: .138
Works accidents without speed cameras: .089
Divide the number of accidents with cameras (.138) by the number without(.089), you get 1.55 — i.e., 55 percent. The same transformation (1.117 / .089) gives you 31 percent.
Is this what the report wants you to conclude? No. Is it doing injustice to the report? NO.
“non-works [personal injury accident] rate is significantly higher for the sites with speed cameras than the rate for sites without.”
They don’t want to give the numbers because that’s not what the UK government paid them to find. The numbers, however, are there.
More replies.
Two additional points in response. Pete Austin made some effective quotes from the summary. Nice work, but the summary compared road works with cameras to open freeways without road works. That’s where you get “no significant difference” in the PIA rate. No surprise there. What we’re concerned with is the cameras and, again, I direct you to the footnote on the chart: Non-works freeways with cameras have a significantly higher injury rate than non-works without speed cameras.
Now, are we just to be lemmings and not ask, how much higher? If the answer isn’t 31 percent, what is it? All the footnote says is that it’s > 5%. And if the study is all sunshine and roses for the cameras, why all the effort to hide it? It was completed 18 months ago, and only made available because the UK FOIA law kicked into effect this year. As for the KSI rate, fewer than 4 people are killed annually in road works in the UK. The fatality statistic is too small to be statistically useful. BBC article.
To Mark — everyone who reads Techdirt knows the patent system is broken. I personally like the constant reinforcement that comes from facts about the situation. If you think I’m trying to be misleading, why would I include links to a complete copy of the study? If I really wanted to mislead, it’d be easy to find (or make) an article that hid the data. I suggest you ought to ask who has something to hide before making assertions like that. The Dept. for Transport is the one who doesn’t want you to read the study.
Speed Cameras Increase Freeway Accidents 31-55%
They are misquoting it, they do have a set agenda and the report was not covered up, it was released in teh same fasion as all of the other reports from the organisation that produced it, the Transport Research Lab.
The press release that started all of the nonesense based around the report was produced from a one page summary of the report. It was generated from one sentence that said there was no significant decrease in fatality accidents at road works with speed cameras compared to those without. It completely ignored the very next sentence that quantified the insgnificant difference which was a reduction of 2%. Significant to some but not to others, it rather depends on your agenda!
The income figures are also wildly misquoted.