I see this a lot, truckies are great for it.

Number one rule for driving in traffic . . . Drive. Don't film.

Oh, don't forget, Econ 101: think of the highway, free market is like that . . . . Yeah, I've never been to a Chicago styled Econ class where they didn't use the highway as an example of free markets where people doing everything they can in their "best" interest causes the whole system to move along quickly . . .

@shatterdrose

Agreed, don't film while driving and the free market is very much like a highway.

At times things zip along quickly, but the selfish motives and aggressive acceleration and deceleration of the typical commuter are the main causes of both volume-related and collision based traffic jams. In much the same way, the risky bets in a Wall Street boom result in a painful economic correction or financial traffic jam.

In fact, there's now a mathematical model that demonstrates the cause of traffic jams (the bilateral-control algorithm.)

http://www.youtube.com/watch?v=Nk87bwAL6PI

I'm impressed by the other drivers actually, there's like, a good 100 ft of foot-to-the-floor-to-get-past-the-two-people-in-front-of-you room.

Around here, if you leave 4 ft in front of you, some short dick with a lifted 1ton dually crew-cab will cut you off and flip you the bird for the privilege.

Traffic is a living being and this guy just makes it worse. It's ok by me tho, I'm the guy going back and forth getting where I'm going hours before him. Traffic is caused by idiots. This guy is one of them.

The roads have a capacity.
~15 feet per car.

100 feet of road will fit about 6 or 7 cars, bumper to bumper.
Alternatively, 100 cars will require 1500 feet of distance to fit.

If a driver keeps 30 feet in front of him, at all times, even when stopped in traffic, then that takes the total per-car size up to 45 feet.
100 feet of road now fits 2 cars.
100 cars now require 4500 feet of distance to fit.

The greater the distance kept between cars, the bigger the strain on road capacity, and the farther back the traffic jam will stretch.



Traffic jams in massive commuter areas do not exist because people are driving too close.

They exist because the rate of people entering the highway exceeds the rate of people exiting the highway, for a long enough duration that the highway 'runs out of room' to fit the cars.

You can widen the roads to increase capacity, so the traffic jam doesn't go as far back.
You can increase highway speed limits, so that people can attempt to 'evacuate' the highway faster.

(Travel-capacity in terms of cars-per-second of any given section of road, is 'cars-per-second-per-lane x number-of-lanes'. Increasing either factor will improve travel.)

...But you can't eliminate the jam.

The rate of 'highway exit' is determined by the number of exits, and the capacity of the exit roads to absorb traffic from the highway.

When people exit from a highway, they usually go into local traffic, and are met by a light within 100 feet.
Between the lights, and other cars looking for parking spots, pedestrians, etc, local traffic is a dog.

Highway traffic can't diffuse out of the exits fast enough, and the traffic backs up on the exit ramps, and then backs up onto the highway. Once the traffic backs up onto the highway, exiting traffic consumes a lane for queuing, which forms a choke.


Basically, to avoid a jam, the rate of people entering the highway can not exceed the maximum possible rate of people exiting and diffusing into the destination city.

Because 'everyone goes to work at once', and local traffic is not geared to rapidly absorb exiting traffic, the jams are unavoidable.

Driving with a massive space in front, refusing to fill in the gap, only uses up the highway's buffering capacity more quickly.
That leads to the 'complete' jam happening sooner, where traffic is queued all the way from the destination, all down the highway, and onto the feeder roads miles away, blocking local traffic elsewhere.




IMO, if people really care abut stopping traffic jams, they should put a commuter parking lot at every exit at major commuter areas.

When you exit off of the highway, you would immediately wind your way through a parking lot, and at the other end of the lot you would exit into local traffic.

The parking lot acts as a buffer, allowing the highway exit lane to not get backed up, and prevents the queue from building up onto the highway.

That way the traffic on the highway can travel without chokes.

Although, this would just move the "parking lot" occurring on the highway, into a literal parking lot. You'd still be stuck waiting a while, as the rate of people exiting the parking lot into local traffic would still be limited by the rate at which local traffic can absorb the highway traffic.

Basically, to have literally no waiting, the city streets absorbing exiting highway traffic need the same uninterrupted cumulative bandwidth as the highway.

In the end, if you want to fix highway traffic jams, fix city streets.




You can make the argument that keeping more space in front will make people more comfortable with driving faster, and traffic will move faster.
But, that faster moving traffic will merely more quickly arrive at the same clogged exit, and queue with the same other cars waiting to get onto the local roads.

-scheherazade

I just commute on a motorcycle instead

"Traffic?......what traffic?...You mean that stuff not moving either side of these special motorbike lanes?"

Get real. This guy knows the pace of the living being, and acts accordingly.

IDK why you guys cant see or understand what this dude is saying.

Stop and go, stop and go traffic starts a chain reaction that just waves along in reverse FOREVER. If everybody was to move along at a slow, steady, and constant speed, traffic would clear up very quickly.

I am a truck driver, and my motto has always been. If people would think collectively, instead of independently. there would be no such thing as traffic.

I'm no expert but everything I've ever heard/read from informed sources (i.e. people who study these things rather than random people on the internet) concurs with exactly you you just said there.

Traffic Jams supposed to act like longitudinal waves that snowball as they go due to people driving too close and needing to overcompensate. i.e. what starts as a few people braking a bit too much becomes 100's of people at a standstill a few miles down the line of traffic.

I think you are entirely correct to suggest that if everyone maintained a healthy distance and steady pace traffic would flow considerably more smoothly and many jams wouldn't even happen in the 1st place.

There are choke points but these need never take up more than a lane if people had some perspective and collective sympathy....

Unfortunately they don't and most (or at least enough) tend to drive like the impatient selfish twats they are. This makes biking gently past all of them in their self inflicted gridlock misery all the more satisfying (wouldn't be the 1st time I've sung the Trololol song while doing so either )

Imagine every truck driver doing it. Traffic jams would be even bigger.

There's some confusion in the comments concerning the difference between smooth flowing traffic and fast flowing traffic.

These are not the same things.

Increasing the distance between you and the car in front of you to maintain a consistent speed will help to buffer the slinky effect in traffic.
It will NOT eliminate traffic jams.
You're actually reducing the efficiency of the highway and causing the slow down behind you to increase.

Decide what you mean by 'traffic jam'. Is it stop-and-go traffic or slow speeds? Follow this guy's advice to stop the slinky, with the negative effect of reducing average highway speed behind you. Fill in the gaps if you dread slow highway traffic, with the negative effect of creating more inconsistency in speeds.

Both @Chairman_woo and @Rawhead are 100% correct.

Traffic behaves like a wave. Canceling the amplitude (not stopping and going all the time, rather going a constant speed) reduces the chain reaction.

If you really want to know the chain reaction happens because people are no machines. They need time to reaccelerate once stopped. This time adds up.

Here is an example of this: http://videosift.com/video/Traffic-Jam-Simulation

@scheherazade it's not about keeping space in front of you. It's about going a constant speed. You're parking lot theory seems to stem from playing Sim City too much.
I do realize less cars = less traffic. But jams will still occur. You just need two cars.

All the research I've ever read/heard from professional sources appears to completely refute what you are suggesting.

Maintaining a decent distance speeds up the average flow of traffic! Being a little further behind doesn't slow anyone down it just makes them further away from each other.

A car doing 30mph 2 feet behind another is going EXACTLY as fast as a car going 30mph 20 feet behind another. Distance between cars doesn't make anyone have to go any slower, simply that they are further away relative to each other.

It also has the benefit of reducing or even preventing the wave phenomenon which SLOWS DOWN the traffic or even stops it dead. (capitals just for emphasis not sarcasm).

The distinction you are suggesting between smooth and fast flowing makes no sense to me. Smooth flowing traffic IS fast flowing traffic. It's the wave effect that slows traffic down not the amount of tarmac taken up.

The physical length of highway a car takes up would only matter if you were trying to park them. I can see why this might seem to matter from the subjective POV of someone stuck in a jam/slow moving traffic. But if everyone maintained distance this situation would be less likely to occur (and reduced in effect when it does).


Smooth traffic is fast traffic. We are not confused. This is based on modern professional studies of traffic dynamics. Having less lanes is know to actually speed up jammed traffic under many circumstances (London M25 springs to mind)


Let me put this another way. Watch that vid again. He isn't going any slower than the flow of traffic he's just further away from the car in front. You can tell this because he's maintaining a steady distance from the car in front. The only people who are being slowed down are the asshats behind him driving bumper to bumper. They experience what seems like a temporary reduction in speed but this is simply an illusion created by giving back the healthy separation between vehicles that should have existed in the 1st place. i.e. they are just "paying back" a few feet of roadspace each, which they took up at a previous point in time. They won't get anywhere any faster or slower as a result & this way it helps to reduce the "slinky effect" which actually does reduce average travel time from point A to B.

As a side issue, smooth slow traffic is definitely better for fuel consumption (and therefore emissions) than stop start traffic, even at a lower average speed.

And he's moving a lot of mass. Stop-and-going, accelerating and stopping that large mass would be quite arguably terribly inefficient economically (wear and tear; increased fuel consumption)---and big rigs being jerked to a stop is scary.