Traffic Light Inefficiencies

Comments criticize poor traffic light timing that forces unnecessary stops, red light cameras manipulated for revenue by shortening yellow lights, and propose better synchronization, sensors, or removal for improved flow and safety.

➡️ Stable 0.6x Politics & Society
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#3974
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Keywords

US AI scientificamerican.com phys.org houstonchronicle.com CSV accidents.html youtube.com fabema.de PR lights traffic red light red light intersection yellow green speed limit cameras

Sample Comments

jsgo Oct 3, 2019 View on HN

I'd be willing to give that a shot; I drive the speed limit in my town (population estimated at about 15.6k), but the lights seem more in relation to current traffic at the intersection. So you catch this red light and you're going straight, you stop and wait. Now when you approach the second light, because you and others were held back there was no one approaching the light so it will likely be red or turning red when you approach. To actually get out of this loop, you basically have

WWLink Sep 4, 2019 View on HN

There were a few intersections in a city I used to live in, where they set up redlight cameras and quickly figured out why people were running the lights. When they changed the order that the lights changed, suddenly nobody ran red lights anymore.I can't remember the exact reason anymore, but it was pretty interesting. Once they fixed the issue, they deactivated the cameras lol.

Tagbert Mar 18, 2022 View on HN

Maybe because the automated enforcement can easily be applied for unexpected goals. In the US, many red light cameras are operated by private companies that are contracted by local governments. They split the revenue. The private companies will then reduce the duration of yellow lights to to increase the number of tickets. The end result is sometimes more accidents as the time from green to red is reduced and more fine revenue is collected. That seems like a perverse incentive for a perverse out

sliken Sep 4, 2019 View on HN

I'd watch the yellow light times. Often they get reduced to increase revenue, even past the legal limits.

mb7733 Jul 5, 2021 View on HN

Green lights... are synchronized to avoid collisions.

jevoten Jan 21, 2022 View on HN

Running a red light is dangerous, therefore let's remove red lights..

Dumblydorr Oct 21, 2019 View on HN

Lights seem incredibly inefficient to me. How many times have I been driving towards a green at the speed limit and it turns yellow just in time to force me to slam on the brakes or the gas pedal, all to let one waiting car go? Why not detect my coming and wait for an efficient yellow timing, thus I am not wasting gas and braking unnecessarily? This would substantially improve carbon emissions and brake dust, yet dozens of times per month, I see lights inefficiently block traffic unnecessarily.

WalterBright Dec 18, 2015 View on HN

Yesterday I was driving past midnight through the city. I'd frequently come to an intersection where 2 arterials crossed at 90 degrees. 3 of the roads had red lights and 2 or more cars backed up. The 4th had a green and no traffic coming at all. And ..... we'd sit there a while, and eventually the light would go yellow, again, for nobody, turn red, pause a second for the non-existent red light runners, then finally turn green for us.The intersections had cameras mounted pointing all

soperj Aug 21, 2014 View on HN

More than anything I'd love to use this to actually improve the way the lights are run downtown in my city. It's insane that they actually use them to make people spend longer in the downtown corp. (when one turns green, the next turns red, there is literally no flow to traffic and would be faster going through a number of stop signs.)

hevang Jan 14, 2025 View on HN

Legality aside, is that not kind of the issue here? Lights in a high foot traffic area could incentivize people to speed up to make it before the red, which is less predictable and has cars traveling at faster speeds compared to a stop sign, which requires all cars to stop. Embellished yes, but point of the article showing that this intersection is now more dangerous to pedestrians stands imo.