4 ms·

I think the statistics are misleading. In cases where the number of "accidents at intersections" fell, I'd like to know whether the number of accidents between

by byoung2 16y ago

I think the statistics are misleading. In cases where the number of "accidents at intersections" fell, I'd like to know whether the number of accidents between the crosswalks fell, while the number of accidents leading up to the intersection rose. I have personally witnessed people either speeding up to beat the camera or slamming on the brakes to avoid getting a ticket. I'd bet that the number of rear-end accidents on approach to camera-monitored intersections increased.

cninja 16y ago
Statistics are always misleading, especially when politics are involved.
zacharycohn 16y ago
I'd love to see a detailed breakdown of the types of accidents too. I know that I have slammed on my brakes when a light turns yellow, or the person in front of me does, and we narrowly avoid a collision. I think it'd also be interesting to know the geography of the area leading up to the light. One in my hometown is at the top of a steep hill, so you pretty much have to be accelerating rather hard to even get to the light. There's an area where you can be in when it switches to yellow where you HAVE to go or destroy your brakes, but it puts you pretty solidly in the middle of the intersection.
Timmy_C 16y ago
You bet right: http://vtrc.virginiadot.org/PubDetails.aspx?PubNo=05-R21 http://vtrc.virginiadot.org/PubDetails.aspx?PubNo=05-R21
- byoung2 16y ago
  A-ha! Further the data show that the cameras are correlated with a definite decrease in crashes that are directly attributable to red light running, a definite increase in rear-end crashes, a possible decrease in angle crashes, a net decrease in injury crashes attributable to red light running, and an increase in total injury crashes. More time is needed to determine whether the severity of the eliminated red light running crashes was greater than that of the induced rear-end crashes.
ergo98 16y ago
Total number of accidents is only a part of the story. I would fully expect minor rear-ending types of accidents to increase, possibly substantially. On the flip side I would expect the deadly T-boning variety to decrease. The unproven assumption being that minor accidents increase, serious accidents decline.
- byoung2 16y ago
  I would expect the deadly T-boning variety to decrease I think this variety of accident happens when the light has been red for quite some time (i.e. more than a few seconds). The people who get tickets (from what I've seen personally, and from talking to police) are people who just missed the yellow light by a few tenths of a second. The latter group are the ones a traffic light cameras are affecting (the ones alert enough to slam on the brakes or speed up). People who run stale red lights (the ones who cause major accidents) are either oblivious to the fact the light is red at all (e.g. drunk drivers), or they don't care (e.g. high speed pursuits).
  - ergo98 16y ago
    You overestimate people's ability to time lights. I have absolutely seen people accelerate to "catch a yellow", and then fall into the red by a substantial period of time. Where the only safety from an accident is that the crossing traffic was aware of them. http://www.iihs.org/research/qanda/rlr.html http://www.iihs.org/research/qanda/rlr.html In addition to reducing red light violations, cameras have been shown to reduce intersection crashes. In Oxnard, California, significant citywide crash reductions followed the introduction of red light cameras, and injury crashes at intersections with traffic signals were reduced by 29 percent.9 Front-into-side collisions — the crash type most closely associated with red light running — were reduced by 32 percent overall, and front-into-side crashes involving injuries were reduced by 68 percent. An Institute review of international red light camera studies concluded that cameras reduce red light violations by 40-50 percent and reduce injury crashes by 25-30 percent.10 Some studies have reported that while red light cameras reduce front-into-side collisions and overall injury crashes, they can increase rear-end crashes. Because the types of crashes prevented by red light cameras tend to be more severe than rear-end crashes, research has shown there is a positive aggregate benefit. Exactly what I said, though I got the requisite downvote from the came-from-Reddit "red light cameras are just money grabs!" ignorant crowd. Though I suppose the IIHS -- the foremost authority on traffic safety -- has less sway than various anecdotes.
mrbird 16y ago
From the report: "We found that the program cannot conclusively demonstrate that it has reduced traffic collisions, thereby increasing public safety." It goes on to recommend that data collection be improved to answer the question of what kinds of collisions and violations are being observed, in greater detail.

by byoung2 16y ago

cninja 16y ago

Statistics are always misleading, especially when politics are involved.

zacharycohn 16y ago

I'd love to see a detailed breakdown of the types of accidents too. I know that I have slammed on my brakes when a light turns yellow, or the person in front of me does, and we narrowly avoid a collision. I think it'd also be interesting to know the geography of the area leading up to the light. One in my hometown is at the top of a steep hill, so you pretty much have to be accelerating rather hard to even get to the light. There's an area where you can be in when it switches to yellow where you HAVE to go or destroy your brakes, but it puts you pretty solidly in the middle of the intersection.

Timmy_C 16y ago

You bet right: http://vtrc.virginiadot.org/PubDetails.aspx?PubNo=05-R21 http://vtrc.virginiadot.org/PubDetails.aspx?PubNo=05-R21

byoung2 16y ago
A-ha! Further the data show that the cameras are correlated with a definite decrease in crashes that are directly attributable to red light running, a definite increase in rear-end crashes, a possible decrease in angle crashes, a net decrease in injury crashes attributable to red light running, and an increase in total injury crashes. More time is needed to determine whether the severity of the eliminated red light running crashes was greater than that of the induced rear-end crashes.

ergo98 16y ago

Total number of accidents is only a part of the story. I would fully expect minor rear-ending types of accidents to increase, possibly substantially. On the flip side I would expect the deadly T-boning variety to decrease. The unproven assumption being that minor accidents increase, serious accidents decline.

byoung2 16y ago
I would expect the deadly T-boning variety to decrease I think this variety of accident happens when the light has been red for quite some time (i.e. more than a few seconds). The people who get tickets (from what I've seen personally, and from talking to police) are people who just missed the yellow light by a few tenths of a second. The latter group are the ones a traffic light cameras are affecting (the ones alert enough to slam on the brakes or speed up). People who run stale red lights (the ones who cause major accidents) are either oblivious to the fact the light is red at all (e.g. drunk drivers), or they don't care (e.g. high speed pursuits).
- ergo98 16y ago
  You overestimate people's ability to time lights. I have absolutely seen people accelerate to "catch a yellow", and then fall into the red by a substantial period of time. Where the only safety from an accident is that the crossing traffic was aware of them. http://www.iihs.org/research/qanda/rlr.html http://www.iihs.org/research/qanda/rlr.html In addition to reducing red light violations, cameras have been shown to reduce intersection crashes. In Oxnard, California, significant citywide crash reductions followed the introduction of red light cameras, and injury crashes at intersections with traffic signals were reduced by 29 percent.9 Front-into-side collisions — the crash type most closely associated with red light running — were reduced by 32 percent overall, and front-into-side crashes involving injuries were reduced by 68 percent. An Institute review of international red light camera studies concluded that cameras reduce red light violations by 40-50 percent and reduce injury crashes by 25-30 percent.10 Some studies have reported that while red light cameras reduce front-into-side collisions and overall injury crashes, they can increase rear-end crashes. Because the types of crashes prevented by red light cameras tend to be more severe than rear-end crashes, research has shown there is a positive aggregate benefit. Exactly what I said, though I got the requisite downvote from the came-from-Reddit "red light cameras are just money grabs!" ignorant crowd. Though I suppose the IIHS -- the foremost authority on traffic safety -- has less sway than various anecdotes.

mrbird 16y ago

From the report: "We found that the program cannot conclusively demonstrate that it has reduced traffic collisions, thereby increasing public safety." It goes on to recommend that data collection be improved to answer the question of what kinds of collisions and violations are being observed, in greater detail.