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Comment by nawitus | Hacker News Reader

>This means raising the price of driving on a road when demand is high. During rush hour, drivers would have to pay a fee to use the most congested roads.

Drivers already pay for the cost in lost time. It's a 'natural' market.

The main problem with this article is the idea that the goal in traffic policy is to reduce congenstion. No, it should be to maximize utility. Sure, if you reduce roads, add congenstion charges then people will find alternatives to cars. That doesn't imply that utility is increased.

Public transportation is typically worse than using a private car. You can't decide when to leave, you pretty much need to plan your trips around public transportation. They don't take you directly from A to B etc. Public transportation becomes effective only when population density becomes high enough.

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> Drivers already pay for the cost in lost time. It's a 'natural' market.

Yes, but it's a negative sum market. The lost time the drivers are paying is lost, it is destroyed, hours that could have been spent in productive work, or in enjoyable leisure are being wasted. Setting up the market to work in dollars rather than hours avoids this. The dollars are transferred but no resource is squandered.

This is typically true in North America, but it is not a fundamental law. Particularly, in Europe, but also for some trips in Sydney, Vancouver, et cetera, I have found public transit superior to a private car. The key is to have as wide of a network as possible, frequent service (every 5 minutes so you don't need to think about schedules) and a average speed that is higher than the car (doable with trains, dedicated bus lanes and so on). Anywhere that there is enough traffic to cause congestion ought to be a viable place for public transportation . . . population density is not necessarily the driving factor. In fact, in some situations, a high population density might allow people to move less as they are closer to shops, work, friends, et cetera, rendering transit less important.

No, the problem with public transit in North America isn't some fundamental flaw with public transit, it is because we tend to half-ass it.

Population density is key to mass transit otherwise you have to spend a lot more money to provide frequent and convenient service. You can't get around the need for high enough ridership to make a transit system financially viable. Sparse population density = higher per rider cost = more difficult to offer frequent service without losing a lot of money.

In North America part of the reason we don't have as much mass transit as other parts of the world is because we like our urban sprawl and that makes it difficult to make the economics work out.

> make a transit system financially viable

I don't know about other parts of Europe, but where I'm from public transit is most definitely not financially viable. Even in the big cities, it produces millions of euro of losses each year. Those are covered by taxes.

The problem in North America isn't [just] the suburban sprawl, it's also that you want to make a profit off of everything. Sometimes some things just need to be a public service because it's better that way.

Roads are (mostly) not free, and also cost millions of (insert currency unit here) which are covered by taxes. In particular, the asphalted road in a residential street occupied without charge by someone's expensive vehicle is being paid for by, among other people, me -- and as a non-car-owner, I gain essentially no benefit from the provision of this parking space. So clearly, we've opted as a society for subsidizing public services -- but only certain services.

I think the difference is in the perception that roads are static and once built just sort of stay there for everyone, whereas public transit has a lot of running costs. Sure roads have a lot of upkeep cost as well, but it's not as obvious.

Then again, the roads I've seen in the US are so shitty I'm [almost] certain there's no upkeep being done anyway.

The way this works in municipalities or low-population regions of states (which is what most people experience traveling through 95% of the United States' road miles) is that roads are left to deteriorate until such time as they can't avoid fixing, and preferentially might be completely rebuilt which takes a different flavor of money that can be subsidized by the federal govt.

Regions with affluent populations and dense metros essentially have their own road budgets and taxes to keep conditions acceptable.

The other problem in the states is that the weather varies very strongly; this coupled with snowplows and road freight does a number on roads in short order. Some stretches have to be resurfaced yearly. Doing this is expensive and disruptive, so sometimes it is only done in the worst spots if the other parts can wait.

Roads have to be maintained, the cost is non-trivial.

The roads in the US are absolutely a dream compared to say Indonesia, or even China where new roads tend to crumble after a few years of iffy maintenance.

I can think of a few benefits you get from your neighbor's parking space, but the most important is the increased economic output of your neighbor due to their happiness with suburban life.

The challenge for mass transit systems in the United States is that if the operating costs are so high that it requires heavy subsidization from taxes it becomes a very tough sell politically. "Our taxes are being raised by how much to subsidize the subway???"

Perhaps that's just a failing of how mass transit systems are sold to the public though. If your mass transit system takes several hundred thousand people off the road every day and significantly reduces gridlock it makes everyone's commute better and wastes a lot less time and gas. Maybe that's how these systems need to be sold rather than, "It'll run profitably after X years."

They also promote economic activity (people can get to work and spend less time commuting). Even cities in red states are striving for more of that (though to be fare, even those cities are mostly blue).

Mass transit in the USA used to be mostly operated by private companies, and yes they made a profit.

I don't think anyone really expects government-run mass transit to be profitable, I for one would be happy if it were less of an enormous money pit. Given the level of corruption in most public transit authorities however, I don't hold out much hope.

The private companies couldn't compete with public subsidized roads that came online in the 20th century. If you want to see transit companies making a profit, try highly dense Japan, and you'll still pay more for it.

As if the USA was a third-world country with a high level of corruption compared to say...China, which many conservatives/libertarians "praise" for its cost and efficiency.

'Drivers already pay the cost in lost time.' Yes, but not all of the cost. If each additional car adds 10 seconds to commutes, each driver will only pay a pittance more for her decision to hit the road. Meanwhile they are imposing large costs of 10 seconds * each driver on the road. Look up the economics of externalities again and you'll see that an additional congestion charge is well founded in theory.

I'm curious why this is being downvoted. Isn't congestion a textbook externality?

Assume 100 drivers each cause 10 seconds of slowdown.

Assume every driver is equally at fault.

Each driver is causing 1000 person-seconds of slowdown.

Each driver is receiving 1000 person-seconds of slowdown.

Seems fair to me, and each driver is paying their exact cost.

It's wrong to look at the externalities drivers output and ignore the externalities drivers input.

No, you have to look at the margin. The other 99 people are already there, and you have to choose whether or not to drive; you slow down everyone after you, but you don't slow yourself down.

Everyone before you chose to inconvenience all comers before and after. In a situation like this, especially because it's iterated every day, these people are clearly choosing to slow, and be slowed by, everyone coming after them. Being on the road first doesn't give you moral superiority.

In some situations the margin of newcomers is a fair way to look at it. But with drivers on the road, these people are all getting up in the morning and choosing to use this road at the same time. It is a continuous reaffirmation, day by day, that this is the path they want, no matter who they slow down, and they accept being slowed in return.

Each driver is causing themselves 10 and everybody else 990. Your analysis acts as if people make decisions as a group.

"Each driver is paying their exact cost." Yes, but on the margin each driver can only choose a small chunk of their cost. Seriously, have you looked at the enormous literature on this? One major annoyance on HN is the way CS people assume that they can independently grok the intricacies of any field.

I'm not trying to argue about the intricacies, I'm pointing out that your original example was terribly flawed.

Assuming drivers actually consider their effect on congestion, they are willingly accepting the congestion of those coming after just as much as they accept the congestion they cause. (Most probably don't consider it but that's beside the point) Most importantly, the drivers are choosing to use the road every day even after seeing the final congestion every day. That's not a marginal decision. They are choosing to accept the final congestion.

But even if you insist on a marginal explanation with actors incapable of anticipating future cars, the average driver is intentionally accepting and causing 500 with past cars, and unwittingly accepting and causing 500 with future cars. Versus your characterization of them only intentionally having 10 delay.

Framing it as a new car 'paying a pittance more' is nonsense. The twentieth car either doesn't travel or attempts to pay 200 to travel. Comparing 190 to 200 is meaningless, because they never had the chance to travel at 190.

You need to count the people who would like to use the road, but must choose their next-best option because the road is too congested for them to use (either that time, or in general).

There is a congestion externality on them despite not using the road.

That's fair, but it probably leaves drivers feeling at least half of the effect they cause, rather than the fraction of a percent implied by seizethecheese.

But that's highly inefficient. Everyone pays in the form of time, but some peoples' time is more valuable. Congestion pricing fixes that.

Some people's money is more valuable as well. Congestion pricing simply tips the balance of the system in favour of people who value time more than money.

Well except that the people paid the least per hour are also the ones who can afford to lose time the least and have the least ability to pay for congestion.

So the people who can least afford to lose time will avoid congested traffic and lose less time? Sounds like that could work out well.

If you wait an extra hour before commuting home because of the cost, I don't call that "lose less time".

> Public transportation is typically worse than using a private car. You can't decide when to leave, you pretty much need to plan your trips around public transportation. They don't take you directly from A to B etc. Public transportation becomes effective only when population density becomes high enough.

When PT is done right, it's much more predictable than private cars. Being able to leave when you want does you no good when you're dealing with unpredictable traffic.

Yep. Solid PT runs on a demand schedule too: during hours heavily traveled a train might run every four minutes; during the dead of night it may not run at all or run infrequency, like every forty-five minutes.

And to the GP's point, they most definitely take you from point A to point B. Those two points may not be where you are and where you want to go, though with a solid network it'll usually be within ambulatory distance.

;)

> Drivers already pay for the cost in lost time. It's a 'natural' market.

Except it's not: unless you're extraordinarily prescient (or have access to real-time, accurate-to-the-meter traffic data), the driver cannot act as a rational actor because he has imperfect knowledge about the transaction. And that's assuming he'd act like a rational actor anyways -- and anyone who's studied real life instead of theory will tell you that most actors are not rational except, sometimes, in aggregate.

> Public transportation is typically worse than using a private car.

Says who? Instead of spending time stressfully navigating through a slow maze of cars, you can read a book while quickly and predictably getting to your destination. (Public transit is substantially more predictable than traffic.)

I'd take a train over a car every time.

In big cities like Tokyo you can just go into the subways/train lines and demand is high enough that you'll only wait maybe 5 or 10 minutes. Not to mention that it's faster than a car most of the time (due to no red lights or the like).

And if you really need A -> B directly, there are taxis.

In the same cities owning a car is also inconvenient, it's not like you can park anywhere.

The fact that public transportation sucks in a lot of cities is not due to intrinsic qualities of these solutions, it's a consequence of shitty urbanisation planning that makes it hard to offer a good public transportation strategy.

Have you not ever been in a traffic jam?

'Traffic jam' is not a good concept to talk about. You need to talk about utility. In more concrete terms, you need to talk about travel time. Talking about whether or not something is a traffic jam or not is simply losing information.

I'm not interested in the definition of a 'traffic jam'. I'm not interested to know if I've ever been in a 'traffic jam' or not.

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