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Washington, Minnesota officially endorse a “safer, faster” traffic merge

arstechnica.com

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Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#61

Post by justinpaulson »

ericHosick wrote: post #40
notacoward wrote: post #27

Zipper merging works great as long as everyone on both sides is willing to alternate (or if strong enforcement requires them to do so). Otherwise, letting "late mergers" scream past fifty "early mergers" often creates a situation worse than simple early merge. There's plenty of blame to go around. * The vast majority of the people blasting down the late-merge lane clearly have no interest in alternating or merging in…

Zipper merging is the optimal solution. People early merge because they think it is the optimal/moral/better/'done my part' solution. If everyone knew about zipper merging there would be no early mergers (and 'late mergers' don't exist within the context of zipper merging).

Zipper merging is only optimal if traffic is already slowed down dramatically. If traffic is still moving at any kind of speed, then early merge when there is space available will clear congestion faster than everyone driving up to the merge point and hoping that it works out.

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#62

Post by slantyyz »

ericHosick wrote: post #40
notacoward wrote: post #27

Zipper merging works great as long as everyone on both sides is willing to alternate (or if strong enforcement requires them to do so). Otherwise, letting "late mergers" scream past fifty "early mergers" often creates a situation worse than simple early merge. There's plenty of blame to go around. * The vast majority of the people blasting down the late-merge lane clearly have no interest in alternating or merging in…

Zipper merging is the optimal solution. People early merge because they think it is the optimal/moral/better/'done my part' solution. If everyone knew about zipper merging there would be no early mergers (and 'late mergers' don't exist within the context of zipper merging).

>> Zipper merging is the optimal solution. People early merge because they think it is the optimal/moral/better/'done my part' solution.

It is optimal only when the local driving culture allows it to be.

I live in an area where drivers are extremely selfish and the police don't seem to spend a lot of time ticketing bad drivers, so zipper merging typically doesn't work here.

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#63

Post by _delirium »

joshwa wrote: post #57
flomo wrote: post #43

Earlier quoted context omitted.

Disagree. I used to reverse-commute through the Golden Gate Bridge and the Caldecott Tunnel, where the freeway went from 4 lanes to 2 in both places. 99% of drivers manage to zipper-merge properly. Likewise, almost everyone zippers at the South 101 Central Freeway merge. California drivers may or may not be bad, but they're much better than the ones in Minnesota.

I wish some of the "exit only" lanes would change to be zipper-merge-able-- in SF, think about the 7th street exit on 80E just before the Bay Bridge-- two empty lanes!-- and lots of "cheaters" whereas with a zipper merge everything would move faster. IIRC California officially endorses early merging, though?

You could just make two exit lanes in that case, and merge them as or after they exit. People exiting at the last minute from a non-exit lane though aren't really merging, but rather changing lanes. And it doesn't really result in a proper zipper merge since not everyone is exiting, so you can't predictably alternate cars.

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#64

Post by slantyyz »

Klinky wrote: post #55
rcthompson wrote: post #52

Earlier quoted context omitted.

If enough people are doing zipper merging, then there is no way to cut in line, because both lanes are equally backed up. Then once people get to the merge point, they won't have any sense of unfairness because the other lane was waiting just as long, so there will be less impetus for "vigilantes" to mess things up. I'm not saying there will be no problems, but I don't think that more zipper merging will automaticall…

The question then is, do enough people zipper merge, and do people really have a proper understanding of fairness? A lot of the driving population may not be acting rationally, or even have enough awareness to comprehend the big the picture. Cars put people into their own bubble, where quite oftenly only their needs are being considered.

>> Cars put people into their own bubble, where often only their needs are being considered.

This is so true. At congested merge points in my city, you have people who don't really care about the alternating needed to make a zipper merge work. First, you have people who just won't let people in, and then you have people who will try to sneak into the lane with the merging car ahead of them.

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#65

Post by peeters »

malandrew wrote: post #35

That video explanation made no sense to me. Basically the "interface" presented to the drivers has not changed, so why would drivers deviate from how they currently merge? Because the government said so? I don't see this working. However there are two solutions that could promote zipper merging: (1) Force both lanes to the center before moving that center lane to the side that is available ahead: ____________________…

I like the idea of #1. But it seems from my experience in the U.S. and Canada, that there is a tendency towards unambiguous right-of-way. That tends to rule out collaborative scenarios where there's no clear "winner" when two cars are competing for the same resource. Which is a shame, because making this collaborative is exactly what will change the mentality (i.e. you can't ignore the drivers trying to merge, because you're trying to merge too).

Even with zipper merging the right-of-way is going to be on the person who is staying in their own lane.

I'm not sure if my experience is regional, or even imagined, nor do I know the reason...I'd imagine it makes assigning blame in an accident much easier, but that's a really crappy basis for traffic rules.

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#66

Post by IgorPartola »

I really wish people would actually do this. I call this "driver karma". For every person you let in, you get to go in front of another person. If everyone followed this heuristic, we wouldn't have a problem. Oh, and if you let a bus full of people in front of you, your score is increased by the number of people on the bus :).

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#67

Post by [deleted] »

john_b wrote: post #59
notacoward wrote: post #27

Zipper merging works great as long as everyone on both sides is willing to alternate (or if strong enforcement requires them to do so). Otherwise, letting "late mergers" scream past fifty "early mergers" often creates a situation worse than simple early merge. There's plenty of blame to go around. * The vast majority of the people blasting down the late-merge lane clearly have no interest in alternating or merging in…

> "Without enforcing proper merge behavior on both sides, zipper merge just becomes a big Prisoners' Dilemma game with a few defectors screwing all of the cooperators." Except unlike prisoner's dilemma, it's not a zero (or negative) sum game. The entire traffic flow can speed up if zipper merging is done. The "late mergers" don't have to risk losing their game of "chicken" while the "vigilantes" don't have to deal wi…

[deleted]

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#68

Post by peeters »

slantyyz wrote: post #62
ericHosick wrote: post #40

Earlier quoted context omitted.

Zipper merging is the optimal solution. People early merge because they think it is the optimal/moral/better/'done my part' solution. If everyone knew about zipper merging there would be no early mergers (and 'late mergers' don't exist within the context of zipper merging).

>> Zipper merging is the optimal solution. People early merge because they think it is the optimal/moral/better/'done my part' solution. It is optimal only when the local driving culture allows it to be. I live in an area where drivers are extremely selfish and the police don't seem to spend a lot of time ticketing bad drivers, so zipper merging typically doesn't work here.

> It is optimal only when the local driving culture allows it to be.

Yeah, which is why almost the entire article was about the campaigns to change the culture, not about justifying zipper merging as optimal.

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#69

Post by joshwa »

_delirium wrote: post #63
joshwa wrote: post #57

Earlier quoted context omitted.

I wish some of the "exit only" lanes would change to be zipper-merge-able-- in SF, think about the 7th street exit on 80E just before the Bay Bridge-- two empty lanes!-- and lots of "cheaters" whereas with a zipper merge everything would move faster. IIRC California officially endorses early merging, though?

You could just make two exit lanes in that case, and merge them as or after they exit. People exiting at the last minute from a non-exit lane though aren't really merging, but rather changing lanes. And it doesn't really result in a proper zipper merge since not everyone is exiting, so you can't predictably alternate cars.

I guess I mean that they shouldn't be exit lanes at all, but should be used as extra capacity to facilitate zipper merges. In the case above, the exit lanes stretch back almost 1/2 a mile, which is waaay above the actual demand for that exit, esp in the evening hours.

Re: Washington, Minnesota officially endorse a “safer, faster” traffic merge

#70

Post by ics »

john_b wrote: post #59
notacoward wrote: post #27

Zipper merging works great as long as everyone on both sides is willing to alternate (or if strong enforcement requires them to do so). Otherwise, letting "late mergers" scream past fifty "early mergers" often creates a situation worse than simple early merge. There's plenty of blame to go around. * The vast majority of the people blasting down the late-merge lane clearly have no interest in alternating or merging in…

> "Without enforcing proper merge behavior on both sides, zipper merge just becomes a big Prisoners' Dilemma game with a few defectors screwing all of the cooperators." Except unlike prisoner's dilemma, it's not a zero (or negative) sum game. The entire traffic flow can speed up if zipper merging is done. The "late mergers" don't have to risk losing their game of "chicken" while the "vigilantes" don't have to deal wi…

> [...] inconveniencing everyone behind them for the self satisfaction of having helped the one person they can see.

Or because you know that otherwise they'll be at that crossing for the next hour if nobody's willing to let them by. Perhaps there are some funny allusions to net neutrality to be made here...

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