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Your ideas about what red light cameras do are contradicted by the actual studies done to see what red light cameras do. https://www.fhwa.dot.gov/publications/r

Your ideas about what red light cameras do are contradicted by the actual studies done to see what red light cameras do. https://www.fhwa.dot.gov/publications/research/safety/05048/05048.pdf https://www.fhwa.dot.gov/publications/research/safety/05048/...

AnthonyMouse 9y ago
Red light cameras increase rear end collisions and decrease side impact collisions; but side impact collisions are more dangerous. The problem, of course, is that there is a better way to reduce side impact collisions -- and red light running in general -- which is to increase the length of the yellow light. But because doing that actually does reduce the number of people who run a red light, the intersections with red light cameras do the opposite of that, because they need people to run red lights in order to generate revenue and pay for the cameras. And if you compare the results at red light camera intersections with short yellow lights against normal intersections with appropriately timed yellow lights, the cameras are killing people.
- obstinate 9y ago
  I'm interested to read a citation that shows that increasing yellow light length is superior to RLCs. Please send it my way. Thank you.
  - AnthonyMouse 9y ago
    Compare the percentages for right-angle crashes on page 63 of your link to the numbers here: http://saferstreetsla.org/wp-content/uploads/reports/A%20Compendium%20of%20Yellow%20Interval%20Increase%20Studies.pdf http://saferstreetsla.org/wp-content/uploads/reports/A%20Com... Assuming the number of right-angle crashes is proportional to the number of people who run red lights, the reduction due to having a longer yellow light is larger than the reduction due to the RLC. And that's before considering the rear-end collisions, which a red light camera increases but a longer yellow light reduces.
    - obstinate 9y ago
      This is interesting, but it seems to mostly be focused on violations rather than crashes. I can see how the two might be related. But I also somewhat suspect that early into red violations may not be the type of red light running that causes accidents the most.
- douche 9y ago
  In my experience, I don't see that longer yellow lights really help much - people just keep going through until the light turns red. At least in this state, as long as you have already entered an intersection before the light turns red, you haven't run the red light. I would think that a better strategy would be to increase the delay before turning the next light green, after the last one turned red.
  - u801e 9y ago
    > In my experience, I don't see that longer yellow lights really help much Studies done in Virginia and Texas contradict that assertion. Increasing the yellow phase time decreased the incidence of red light running and the effect was sustained over time.
reitanqild 9y ago
Around here red light cameras where removed. I heard it was because they where found to significantly increase accidents.
- LoSboccacc 9y ago
  It's a complex matter. The company demands to retain control over the camera and makes the municipality pay rent if not enough tickets are issued. Rlc issue is that incentive structure is all wrong, which lead to shortened yellows and people doing emergency braking at the slightest hint of light change.
  - reitanqild 9y ago
    Around here is not US and while I haven't seen anything written about such incentives I think that might be because any setup like that would be found illegal.
- obstinate 9y ago
  Your "I heard" is not a relevant response to my linked meta-analysis.
Retric 9y ago
That's not what your link says, there is a modest aggregate crash cost benefit of RLC systems. It found this by: The economic analysis examined the extent to which the increase in rear end crashes negates the benefits for decreased right-angle crashes. Rear end crashes cost less than right angle crashes. Further this does not mean there was a lower severity of crashes simply fixing doors costs more.
- obstinate 9y ago
  It examined the extent to which the rear end crashes negated the economic advantages, and found that they did not fully negate the economic advantages. They instead had an economic advantage of ~40-50k USD per site per year. See pages 5, 68, 74. This is why it's important to go further into papers than just reading the abstract.
  - Retric 9y ago
    I say they increase accidents you say, that's not true they lower costs. I say that does not mean they lower accidents. You respond yes they do, they lower cost. Do you really want me to say that's not my argument using different words? If your point is sure they cause more accidents but that's ok because X then use that argument don't pretend there are zero costs. PS: Economic arguments are very easy to manipulate based on what you do and do not count. So, yes I also disagree with the study, but that's not the argument I am making.

AnthonyMouse 9y ago

Red light cameras increase rear end collisions and decrease side impact collisions; but side impact collisions are more dangerous. The problem, of course, is that there is a better way to reduce side impact collisions -- and red light running in general -- which is to increase the length of the yellow light. But because doing that actually does reduce the number of people who run a red light, the intersections with red light cameras do the opposite of that, because they need people to run red lights in order to generate revenue and pay for the cameras. And if you compare the results at red light camera intersections with short yellow lights against normal intersections with appropriately timed yellow lights, the cameras are killing people.

obstinate 9y ago
I'm interested to read a citation that shows that increasing yellow light length is superior to RLCs. Please send it my way. Thank you.
- AnthonyMouse 9y ago
  Compare the percentages for right-angle crashes on page 63 of your link to the numbers here: http://saferstreetsla.org/wp-content/uploads/reports/A%20Compendium%20of%20Yellow%20Interval%20Increase%20Studies.pdf http://saferstreetsla.org/wp-content/uploads/reports/A%20Com... Assuming the number of right-angle crashes is proportional to the number of people who run red lights, the reduction due to having a longer yellow light is larger than the reduction due to the RLC. And that's before considering the rear-end collisions, which a red light camera increases but a longer yellow light reduces.
  - obstinate 9y ago
    This is interesting, but it seems to mostly be focused on violations rather than crashes. I can see how the two might be related. But I also somewhat suspect that early into red violations may not be the type of red light running that causes accidents the most.
douche 9y ago
In my experience, I don't see that longer yellow lights really help much - people just keep going through until the light turns red. At least in this state, as long as you have already entered an intersection before the light turns red, you haven't run the red light. I would think that a better strategy would be to increase the delay before turning the next light green, after the last one turned red.
- u801e 9y ago
  > In my experience, I don't see that longer yellow lights really help much Studies done in Virginia and Texas contradict that assertion. Increasing the yellow phase time decreased the incidence of red light running and the effect was sustained over time.

reitanqild 9y ago

Around here red light cameras where removed. I heard it was because they where found to significantly increase accidents.

LoSboccacc 9y ago
It's a complex matter. The company demands to retain control over the camera and makes the municipality pay rent if not enough tickets are issued. Rlc issue is that incentive structure is all wrong, which lead to shortened yellows and people doing emergency braking at the slightest hint of light change.
- reitanqild 9y ago
  Around here is not US and while I haven't seen anything written about such incentives I think that might be because any setup like that would be found illegal.
obstinate 9y ago
Your "I heard" is not a relevant response to my linked meta-analysis.

Retric 9y ago

That's not what your link says, there is a modest aggregate crash cost benefit of RLC systems. It found this by: The economic analysis examined the extent to which the increase in rear end crashes negates the benefits for decreased right-angle crashes. Rear end crashes cost less than right angle crashes. Further this does not mean there was a lower severity of crashes simply fixing doors costs more.

obstinate 9y ago
It examined the extent to which the rear end crashes negated the economic advantages, and found that they did not fully negate the economic advantages. They instead had an economic advantage of ~40-50k USD per site per year. See pages 5, 68, 74. This is why it's important to go further into papers than just reading the abstract.
- Retric 9y ago
  I say they increase accidents you say, that's not true they lower costs. I say that does not mean they lower accidents. You respond yes they do, they lower cost. Do you really want me to say that's not my argument using different words? If your point is sure they cause more accidents but that's ok because X then use that argument don't pretend there are zero costs. PS: Economic arguments are very easy to manipulate based on what you do and do not count. So, yes I also disagree with the study, but that's not the argument I am making.