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submitted 1 month ago* (last edited 1 month ago) by lgsp@feddit.it to c/fuckcars@lemmy.world

Those who use the bike know this very well: in the city, speeding motorists overtaking other cars, only get one thing: they arrive first to the next red.

With a simple model, the author estimated the probability that one car that overtakes another, will then be reached again at a later red light. Then he estimated the probability that the same thing will happen when there are multiple successive traffic lights, as usual in the cities.

The result is that as fast as an aggressive driver goes, the presence of multiple traffic lights makes it virtually certain that a slower driver will catch up

So, if someone aggressively overcomes you, when you reach him at the next traffic light, you can tell him that it is mathematically proven that he/she is an idiot.

In addition, this study has implications for the 30 km/h city, demonstrating how in urban areas the traffic lights determine the travel times, not the maximum speed reachable between one traffic light and the next.

The original scientific article is here: https://royalsocietypublishing.org/rsos/article/13/4/260310/481212/The-Voorhees-law-of-traffic-a-stochastic-model

crossposted from: https://poliversity.it/users/rivoluzioneurbanamobilita/statuses/116419204210303856

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[-] AA5B@lemmy.world 5 points 1 month ago* (last edited 1 month ago)

This is where you get to properly reducing lanes can improve speeds.

My town has a major road lined with strip malls that used to be two lanes in each direction. It was also one of the most dangerous and aggravating roads as there was always someone maneuvering for position, and sudden stops or lane changes when someone wanted to turn.

Then a few years back they restriped it, plus coordinated the lights. Now it’s one lane in each direction and that lane is a through lane. Every strip mall gets a dedicated turn lane, so there’s no more reason to maneuver, no more sudden stops or lane changes. The stop lights are more likely to let you through.

Now it’s clear and measurable, everyone’s individual speed is down, accidents are down, but stopping for any reason is way down so you get through the busy section noticeable faster. And it’s much calmer

[-] PapaStevesy@lemmy.world 3 points 1 month ago

This doesn't take into account the vast safety benefits of getting away from incompetent/inattentive drivers. I'm not necessarily passing you to "get there" faster, it's pretty easy to tell when a driver has no clue what they're doing and I don't want to have anything to do with that shit.

I actually have no clue if it doesn't take that into account, I didn't read the article, but you see what I'm saying.

I find I want the incompetent/inattentive drivers far off in front of me. Behind me I have a harder time keeping an eye on them along with everyone else. Far ahead, I have a better chance of reacting and correcting to their improper driving.

[-] PapaStevesy@lemmy.world 1 points 1 month ago

Like I said I'm a different reply, It's not in anyone's best interest for me to go 15 to 30 mph below the flow of traffic just because I ended up behind someone who doesn't know they're on Earth much less operating an automobile. If there's a legal way to pass them, I'm going to. Once they're behind you, you only have to worry about getting rear-ended at a stop, which is only an issue in slower city traffic where it is easier to keep an eye on someone behind you. In which case, just stay in the lane you used to get around them.

If they're driving erratically, however that's another story and I definitely agree that I want to stay as far back from them as I can. But they're usually speeding and my whole point is centered on the premise of being stuck behind a slow inattentive or otherwise neglegent driver. They don't even need to be a bad driver, maybe they're new to the area, looking for parking, having a medical issue, etc. Just pointing out that not all overtaking is about getting there first.

[-] magnue@lemmy.world 3 points 1 month ago

Yeah but what about when you leave the city and you just happen to pass that one car that wants to do 30 in a 60 on a straight road. Worth.

[-] mmcintyre@lemmy.world 1 points 1 month ago

No red lights in the country. After you pass that slow car it ain't got no way of catching up to you.

[-] MML@sh.itjust.works 1 points 1 month ago

Oh but now you passed me!? I'm going to accelerate to 75! Driving in the US is awesome.

[-] psud@aussie.zone 1 points 1 month ago

And then pass me and slow back down, right?

[-] UndergroundParking@lemmy.cafe 3 points 1 month ago

Till first light - yes. But then I won't get the penalty of you being slow or on your phone. You won't be behind me at the second light.

[-] kossa@feddit.org 2 points 1 month ago* (last edited 1 month ago)

Joke's on the math. In my city people who overtake dangerously also just go through a red light anyway. Idiots.

Edit: only once I witnessed the sweet sweet karma. Very smart person was going in the bus lane to overtake everybody else. But another very smart person just wanted to get into the bus lane as well to overtake everybody else. "Crash" (well, luckily only dented cars) followed, but I guess they were both late to their important destinations than everybody waiting in line.

[-] IDew@lemmy.zip 2 points 1 month ago

I always say to myself when someone impatiently overtakes me: "See you at the next red light!"

[-] SuiXi3D@fedia.io 2 points 1 month ago

For me it’s, “Wow, you sure did get to that light before everyone else. Good job!”

[-] brewery@feddit.uk 2 points 1 month ago

I see this every week when I drive to the office. Most of the route is 20mph and single lane. I go at the speed limit and every 2/3 weeks one will overtake me. I'll then see them at the next light, then there next one, then the roundabout, etc for the next 30 minutes. I'll usually then go past them as theres one junction with 2 lanes and they always seem to go in the "fast" lane so they end up behind me when it goes down to one. Makes me so happy everytime!

Sometimes you see it when walking even in a black traffic spot - you'll get to the lights before the cars you've passed sitting there.

Im doing to build my fitness up to cycle the route and think it'll take roughly the same time.

Unfortunately the route is really difficult and long on public transport - it's easy to get into central and back but trying to go across the edge to the other side was never designed for

[-] Mongostein@lemmy.ca 2 points 1 month ago

You’re also wasting gas accelerating to speeds that don’t get you anywhere any faster

[-] driving_crooner@lemmy.eco.br 1 points 1 month ago

This happens with me all the time in my e-bike, max speed is 40 or 50 in some roads, and I can go confortable at 30. They horn me, overpass me only to me to catch them on the next red and I pass them again

[-] FatVegan@leminal.space 1 points 1 month ago

I don't even overtake ebikes with a number plate. What ist even the point. But people freak oyt behind.

[-] MachineFab812@discuss.tchncs.de 1 points 1 month ago

What's the point in registering an "eBike" that can't keep-up with traffic? They're either lying that it can, or simply refusing to do so.

[-] MachineFab812@discuss.tchncs.de -1 points 1 month ago

You're the reason so many roads have a minimum-speed of 40mph. You're right that honking at you and trying to pass when there isn't PLENTY of room to do so is pointless, but only those two things, and I doubt the article is about your specific brand of non-sense.

[-] driving_crooner@lemmy.eco.br 2 points 1 month ago

Tell me how useful is a minimum speed if they're going to stop anyway on the next red light? If anything it shows how stupid is having speed limits higher of 30kmh in cities

[-] MachineFab812@discuss.tchncs.de 0 points 1 month ago* (last edited 1 month ago)

You realize light-timings are calibrated and coordinated based-on intended traffic speeds, right? Just because the speeders get stopped at the next light doesn't mean a too-slow driver doesn't get stopped by that same light after the speeder's got their green and gone-on.

Apparently you've never been on one of the roads I mentioned long-enough to notice they tend to have 4-lanes and lights spaced over a mile-apart, but even on a regular road with room to pass, demanding no-one do-so while you putter-along at just-over-half the speed limit is asinine. Drivers can pass farm-equipment that takes up a lane-and-a-half, stopped emergency-vehicles/cops, mail-trucks, busses, street sweepers and dumptrucks, but not you?

So where's the part about what your asking in any way resembles sharing the road again? The article doesn't even mention bikes, golf carts, or glorified mobility-scooters, btw.

Oh, and it literally says the opposite of what OP claims, even between motor vehicles moving with normal traffic, not obstructing it:

That means, on average, the lead of one car over the other remains the same after the light as before.

The results suggest the idea the slower car will inevitably catch up at the lights is something of an illusion.

[-] Hawke@lemmy.world 2 points 1 month ago

I think your hyphen-minus key is acting up.

[-] MachineFab812@discuss.tchncs.de -2 points 1 month ago* (last edited 1 month ago)

I would rather be called an AI than deal with the confusion that results when I don't link certain words and phrases as thoroughly as I can. The language's propensity for and inconistency with hyphenated words isn't my fault either.

The older I get, the more I think I should just switch to Chinese or some other such language and never look back.

Edit: I took the opportunity to remove as many hyphens as I felt comfortable with removing. I really can't complain that you called me out for what amounts to lazy composition and editting on my part.

[-] psud@aussie.zone -1 points 1 month ago

Timed lights — a road near me has four sets of traffic lights spread a kilometre apart, then at one end it becomes clear for 30km, the other end becomes a minor road

They used to use timed lights to force people onto the slower speed limit (100 for the 30km uninterrupted; 80 for the area controlled by traffic lights)

But the timing caused increasing delays on another major road that crosses at one of the traffic lights, so now they're running as individual intersections

Anyway with four sets of lights you might be stopped at any of them but you're quickly on the open road where the cars travelling at 95km/h (and 80 past speed cameras) will take 19 minutes where I'll only take 18 minutes (travelling at the speed limit) and the utes doing 110 will only take 16 and a third minutes

(It hardly matters)

[-] MachineFab812@discuss.tchncs.de 1 points 1 month ago

Your last three words, in hyphens, is exactly my point. It should matter no more to those advocating they should be able to drive or ride as slowly as they want, than it does to those who pass them.

I have no problem sharing the road with farm-equipment, bikes, horses, carriages, what-have-you, and respecting signs/markings that indicate no passing, or even prohibit just the passing of specific categories.

Fact is, those signs already exist and aren't in the places people in this thread are acting like such rules should be in-effect, so at what point is x passing you no longer offensive? Emergency vehicles? Busses? Car-pooling vehicles? Should you as a bike-rider be free to stop and inspect random cars to see if they hold enough passengers in that moment to be qualified to pass you?

You're right, it doesn't matter, there will always be slower and faster vehicles, and passing, no matter how much/many idiots label themselves "Vorhees" and ignore studies that show their claims versus passing vehicles amount to horse-shit, even when the scenario is setup to promote the idea.

Share the road means share the road, from both ends. As a bike-rider, I found nothing more frustrating than when a death-machine, shortly holding-up a row of death-machines, chose to pace me from behind and in-line with myself. Their following distance was almost never enough to have saved my life if I popped a tire or otherwise fell in a moment when they weren't paying perfect attention, and let's be real; Drivers don't use every-excuse to drive slowly when their vision, reflexes, and even attention-to-detail are top-notch.

The slow drivers are literally the last ones an even slower, more vulnerable, means of transport should want to share the road with, and pacing an even slower vehicle isn't "solidarity"; It's menace.

[-] Alcoholicorn@mander.xyz 1 points 1 month ago

When you filter at a red light on a motorcycle and the driver that was aggressively swerving all over the place yells about how dangerous and illegal it is.

[-] psud@aussie.zone 1 points 1 month ago

They just made motorcycle filtering legal in my town, given how much quicker even slow bikes are than most cars it works well

[-] jtrek@startrek.website 1 points 1 month ago

This matches my intuition. I extremely rarely do any city driving (I don't even own a car anymore) but like... You're not going to go that much faster. You're probably not driving very far. The total amount of time can't be that big.

[-] HubertManne@piefed.social 2 points 1 month ago

even on the highway I kinda looked at it like this. If I travel 1mph I can get there twice as fast at 2mph and on and on. so ou get to 64 and its like. ok so the next step is 128? no thank you. I mean its going to be depending on the measurments used but your still going to max out somewhere around there just due to how it works. Add in you are in energy efficient loss territory and its a no brainer.

[-] sorter_plainview@lemmy.today 1 points 1 month ago* (last edited 1 month ago)

My mental model is slightly different. I think of average speed of the car between source and destination. Every segment of the road will have an average speed at a given time, which may vary depending on the time of the day. This average speed is dictated by numerous factors, including traffic lights, number of slow vehicles on the road, speed limits, etc. You cannot really go significantly higher than this average speed, even if you try as aggressively as possible.

There are exception, especially in Asian roads. If you are a large vehicle, who doesn't care about the law and limits, and they do very aggressive driving, then they go at a larger average speed. I have some completely asshole private bus services in my country.

[-] psud@aussie.zone 1 points 1 month ago

My very spread out city has two roads between its southern suburbs and the city, each is about 30km long

Both only have speed cameras to control speed

So most people drive at what their car tells them is the speed limit, which almost always is 5km/h slow, then a few follow of public safety advice and drive 5km/h under the limit, so actually at -10 and very few have accurate speedometers or GPS that tells them their actual speed and try to travel at the speed limit, and a small number deliberately speeding

Then when we reach the speed cameras the cars going slow all slow more, the speeding cars slow down to well under the limit, and the very few confident drivers try to continue at the limit

Traffic is really smooth and will behaved before the speed cameras, and a hundred metres after them

[-] GreyEyedGhost@piefed.ca -1 points 1 month ago

I find people who say this don't properly account for their time waiting at lights. Sure, you may be going faster when you aren't stopped, but you will catch those reds more often and will be stopped longer, reducing those average speeds. Which is the entire point of the article.

[-] Bubbaonthebeach@lemmy.ca 1 points 1 month ago

Unless I am following a very heavy vehicle that takes a long time to get up to speed, I find there is almost no reason to pass the other traffic. Very seldom do the cars dashing around me get to the next light before it changes unless they are exceeding the speed limit by excessive amounts in which they are even more likely to cause a crash and still not beat me to the next light or other destination.

[-] MachineFab812@discuss.tchncs.de 1 points 1 month ago* (last edited 1 month ago)

Assuming that the traffic light changes colour based on a set time cycle rather than a sensor, and that the cars are travelling on a single-lane road, the results reveal that, taking into account the probabilities of each of the four scenarios, on average the possible gains and losses in spacing between the cars balance exactly.

... that's the opposite of most lights where I live. Even at midnight hours where many switch to timed-mode, there are many that won't change at-all unless a heavy-enough vehicle is in certain lanes, and even many cars get stuck having to exercise the rules about such that were meant for motorcycles and bicycles.

[-] psud@aussie.zone 0 points 1 month ago

heavy enough

It's nearly never about weight, the sensor is a metal detector my steel bike triggers lights easily, my carbon fibre bike doesn't trigger any except the newest which can see the metal in my pedals and chain in the bike area — it's really nice when you roll up to a light and see the loops embedded in the bike holding area

The bike holding area is also good, it puts bikes where drivers can't fail to see them

[-] MachineFab812@discuss.tchncs.de 1 points 1 month ago

Again, making assumptions about what every light will be like. Different places installed different things at different times. Sensors fail. Programming gets updated and introduces errors. My city has a dozen or-so painted cross-walks at intersections that work as I've described previously, and without any buttons for pedestrians to push to make the light change; Those lights will NEVER change for a pedestrian at night. The "exceptions" laws stay on the books for many different reasons, reasons that will likely never go-away.

Literally no-one here is arguing against "bike holding areas"(?), but if you want to argue there should never be exceptions, exceptions made to accomodate bikes and pedestrians of all things, you're gonna have a bad time.

[-] HubertManne@piefed.social 1 points 1 month ago

I have experienced this. Someone with a distinctive enough car will get annoyed at my hypermiling and speed around. More often than not having to stop suddenly at the next light while I glide in but maybe they just make it. Later though I will be gliding in just as the green changes and they are there stopped while I just coast on through starting to accelerate as distance increases.

this post was submitted on 18 Apr 2026
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