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How traffic actually works

jliszka.github.io

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Re: How traffic actually works

#51

Post by nether »

joosters wrote: post #33

What an arrogant article. How can you title something 'How traffic actually works' when you don't examine actual traffic. Instead, make up a simple model, run some code, claim it shows what you want. It's not like modelling traffic is so insanely hard that we need such simplistic models. Pick as complex a model as you like; we have the computing power to simulate it!

He's derived the fundamental diagram of traffic flow: https://en.wikipedia.org/wiki/Fundamental_diagram_of_traffic....

Up next: why F = ma really, really matters for space launches. Experts don't know this!

Re: How traffic actually works

#52

Post by dvanduzer »

DanBC wrote: post #43
unoti wrote: post #23

There are cases where leaving a greater-than-normal lane spacing makes sense, in the interest of safety. Safety is something utterly ignored in the fascinating analysis in this article. For example, if I'm in a left lane buzzing along at wide-open freeway speeds and the right lane next to me is congested and backed up and not moving, I leave more than normal spacing in front of me. Why? Because it's very likely that…

Shouldn't you leave less space, to dissuade people from jumping in the gap?

No! Read the original article this author is trying to critique.

Re: How traffic actually works

#53

Post by jwallaceparker »

I wish more drivers would follow the driving etiquette that advises one to "stay right except to pass."

On every highway trip I see countless cars camped out in the left lane but moving at the same rate as the rest of traffic.

One should only use the left lane for passing. Otherwise, stay right.

Traffic flows smoothly when people follow this system.

Re: How traffic actually works

#54

Post by szirka »

I honestly believe it's the quick decrease in speed by drivers that causes non-accident traffic jams during rush hour.

Don't hit the brakes before merging and when someone merges in front of you, you should have kept enough space so you do not need to hit the brakes. Really, I think traffic would move much smoother if drivers leave at minimum 2 car lengths of open space between the vehicles in front of them and only hit the brakes on the highway when it is absolutely necessary.

If all the cars are put to a halt because of quick and hard braking cars ahead of them, its going to cause a chain reaction that is way more time consuming to drivers behind you than the author's "2 seconds slower to destination" factor due to a merge in front of you.

Re: How traffic actually works

#56

Post by HelloMcFly »

dvanduzer wrote: post #49
HelloMcFly wrote: post #34

Earlier quoted context omitted.

I don't know why people get so mad about this. You use the term "right lane", but what does that mean? It only means what you want it to mean in a given situation. The lane is open until it is not, and as long as both lanes are open they are both "right" (in the non-directional sense, obviously). Why rely on clearly nebulous (sometimes variable, sometimes non-existent) social norms rather than concrete traffic norms?…

There are known choke points where traffic is forced to merge. There is the occasional tourist, but rush hour happens every weekday . People know about these merge points, see traffic backing up in all lanes, and will still jump into the lane about to end trying to rush around a few extra cars. It's rude, and it demonstrably increases traffic.

Okay, when do you think people should start merging? Thirty feet before the "choke point"? One hundred feet? One mile? Three miles?

It's an arbitrary game, and everyone makes up their own "rules of decency" and gets mad when someone follows the rules of the road rather than the rules of their head. Yes, people "know" about choke points, but that doesn't mean it's wrong (or rude) to use open lanes. So long as those lanes are open, they are going to be used, so everyone may as well make use of the space.

Is it my fault that others choose not to use those lanes? No. Is it your fault that it upsets you? Yes. It's not rude. I'm not being impolite. I wish everyone would just follow the same set of rules so we could stop being mad at each other. Which set of rules should we follow? I vote against the ones that change in with the person you're asking.

Having said that, I don't really like when people change lanes just to jump ahead of one or two cars. It doesn't upset me and I think it's fair game so long as it's done safely, but I empathize with the distaste for that a little more.

Re: How traffic actually works

#57

Post by isaacaggrey »

jliszka wrote: post #4
themodelplumber wrote: post #3

Great. I really hope that like 100% of jerk drivers do not find out about this. Never let people merge in front of you...geez man, really?

That was a joke ;) Onramp regulators are the real answer, letting only 1 car merge into traffic at a time at a rate well under 1 every 2 seconds.

> That was a joke ;)

I found your article interesting in light of the popular traffic piece you mentioned, but ending it with jokey suggestions after a fairly serious analysis doesn't really make it clear if you're joking or not.

But hey, maybe @themodelplumber and I are the only two who thought you were serious.

Re: How traffic actually works

#58

Post by maxerickson »

CodeCube wrote: post #41
jameshart wrote: post #17

Earlier quoted context omitted.

re spinning up a new lane: the A38-M Aston Expressway into Birmingham, UK dynamically multiplexes its lanes together into variable width channels depending on the required upstream/downstream bandwidth :) - http://i3.birminghammail.co.uk/incoming/article1294911.ece/A...

aww hell no. I'd be terrified of merging into that lane with no highway divider between me and oncoming traffic. Small two lane highways are bad enough! :P

There are less terrifying, less dynamic alternatives:

http://en.wikipedia.org/wiki/Barrier_transfer_machine

Re: How traffic actually works

#59

Post by acomms »

"At the risk of being helpful, here are some things YOU can do that are actually guaranteed to improve commute times for everyone: ... 2. Don’t let people merge in front of you, ever."

How will the commute times of those who sit there waiting to merge be improved? If traffic flow was heavy enough they would never merge.

If they didn't pack a sandwich they'd starve!

Re: How traffic actually works

#60

Post by [deleted] »

DanBC wrote: post #43
unoti wrote: post #23

There are cases where leaving a greater-than-normal lane spacing makes sense, in the interest of safety. Safety is something utterly ignored in the fascinating analysis in this article. For example, if I'm in a left lane buzzing along at wide-open freeway speeds and the right lane next to me is congested and backed up and not moving, I leave more than normal spacing in front of me. Why? Because it's very likely that…

Shouldn't you leave less space, to dissuade people from jumping in the gap?

[deleted]
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