Comment by Frost1x | Hacker News Reader

Comment by Frost1x | Hacker News Reader

It seems similar to anecdata as the US migrated from dialup to broadband internet services. In theory you could finish downloading everything you needed in a fraction of the time so the bandwidth should remain unused longer.

In practice, people started downloading everything. I just need this Linux distribution but here's a dozen more I can now get in minutes and try out that were prohibitive to download before to experiment with but now aren't. People started downloading video game demos like crazy, setup file servers on their home systems, etc.

It turns out the new efficiencies tend to be quickly gobbled up by existing processes that were stonewalled before. As long as there are problems bound by some technological constraint, any efficiency gains disappear rapidly as they're quickly integrated into existing or new processes. You didn't use that much bandwidth before because it was scarce but now you have a firehydrant so let's see what we can use. Humans are pretty great at quickly finding ways to gobble up and expand resources whenever they're found. Once you break one of those barriers it may be that the other barriers weren't as unsormountable which leads to rapid rise in demand. That's been my 2 cents.

I think that would fall under a slightly different but very similar concept know as induced demand. Basically that occurs when an increase in supply leads to an increase in demand.

Roads are the most commons example of induced demand. Adding new roads rarely decreases travel times because new roads encourage more people to drive which leads to more traffic that soaks up any benefit the new roads added.

The impact is the same regardless of whether the supply increase is real in a quantifiable way or whether the actual amount is fixed but the same quantity is able to satisfy more buyers due to an increase in efficiency.

Your example is more induced demand because we weren't making more efficient use of existing bandwidth. More bandwidth was now being supplied which caused demand to also increase.

It seems like Jevons Paradox is just another example of induced demand, the demand is just induced due to increased efficiency.

Roads and bandwidth can be structured as a Jevons Paradox as well, no? The roads were made more efficient by being able to transport more cars. The Internet connection was made more efficient by allowing more bandwidth.

I think the difference is a real vs nominal increase in supply. Is the quantity of supply higher or is the supply just being used more efficiently? It is the difference between roads being added and the speed limit being increased.

Lots of topics in economics are talked about as if they occur in isolation, but that rarely happens in practice. The bandwidth example includes both because we were increasing efficiency of existing data lines as well as adding more lines, but I think the latter was much more impactful than the former.

Cars are just very space inefficient compared to motorcycle, bicycles, or even pedestrians, though.

Saturation comes much faster for cars, so it's more efficient to use rail and other form of transport.

They are very time efficient, though, and people tend to care about time efficiency too, not just about space efficiency.

But the space inefficiency forces time inefficiency rather quickly ( because cars take so much space, it's relatively easy for them to be enough to create traffic and/or parking congestion). Not to mention the fact that all of the space dedicated to fit the space inefficient cars is wasted, and wastes time for humans ( e.g. when having to cross a huge stroad or parking lot).

Time efficiency, maybe, but time utilization definitely not. Based on current times from Google Maps, driving from New York City to Boston is 3h45m. Taking a Greyhound bus is 4h20m, but you can read a book, play video games, etc during that time. One of them uses the majority of your attention for the full duration, while the other uses barely any of your attention, leaving you free to do something else.

And that's not even counting trains, which would make the same trip in 3h30m.

Okay, and how do you get from the Greyhound station to where you actually want to be? With a car, you can get directly from your home to where you want to be, which makes enormous difference in practice, especially on shorter, intra-city routes.

Cars only work if someone build infrastructure for them and land use pattern is built for them. Think about gas station, garage, etc.

We could use bikes for last mile transport, or make streetcar suburbs an automatic assumption.

> Cars only work if someone build infrastructure for them and land use pattern is built for them.

That's a fully general argument against everything. Buses and streetcars also work only if someone builds infrastructure and land use pattern is built for them.

Of course. So, the idea that car is time efficient doesn't seem to really hold water even when our urban landscape is designed for it, especially in my lived experience.

Is it really going to be all that useful for me if I only walk 5 minutes as opposed to driving 5 minutes to a local convenience store? Especially given the cost on society?

If you can get to a store by a car, you could get to a store by a motor bike.

I have a really hard time justifying myself that I need a one or two ton electric vehicle that can seat five people just to get a drink at that corner shop only accessible by driving.

In congested areas cars are not particularly time efficient. For most journeys up to ten kilometers or so I'm almost as fast on my bike than I would be in a car, sometimes I'm even a bit faster. And that's despite traffic lights not really being optimized for bike traffic.

"Induced demand" usually happens when the product you are supplying is free, like roads.

What you are talking is more like latent demand.

> Roads are the most commons example of induced demand. Adding new roads rarely decreases travel times because new roads encourage more people to drive which leads to more traffic that soaks up any benefit the new roads added.

The problem with "induced demand" is that it's misnamed. It's really suppressed demand.

Suppose you have a congested road. It has two lanes and currently has enough traffic to require three lanes. So you add a third lane. Then you turn around and it's congested again.

Because the congestion suppresses demand. The third lane relieved some of the congestion which increased use. To satisfy the demand that exists when there isn't any congestion, you would need four lanes.

But not necessarily five, because once the congestion is gone, adding more lanes doesn't make it any more gone. If you built a twenty lane road there, traffic to fill it wouldn't just magically appear. (China has done the experiment.)

This is important because it applies to anything else you want to use to relieve the congestion. "Don't build more roads, that's induced demand. The only solution is more mass transit." But if you build the mass transit and it removes one lane worth of traffic from the road, that's the same result as adding the third lane. Which isn't enough for the same reason -- the reduction in congestion increases use of the road. Because the demand isn't being induced by a wider road, it's being suppressed by the existing congestion.

The internet speeds are a great example. In the dial up days, the low speed heavily suppressed demand. Your connection was pretty much maxed out whenever you were using it. Now connections are 1000 times faster or more and we use what, 20 times more bandwidth? Maybe 100 times? The speed increases outpaced the usage increases. It's possible to do that.

> But if you build the mass transit and it removes one lane worth of traffic from the road, that's the same result as adding the third lane.

Mass transit can handle much more than one lane worth of traffic.

> Mass transit can handle much more than one lane worth of traffic.

It's not about how many people you can physically fit on a train car. They all have to be going the same way or it doesn't work.

There could be one lane worth of people who are doing that and the others are going to thousands of different places.

I read this mostly as a semantic difference. Both supply and demand generally exist as curves and changing the position of the supply curve changes the position it intersects with the demand curve. The demand curve isn't actually changing. Whether we call that move from the first intersection to the second "induced demand" or "release of suppressed demand" doesn't really matter in my opinion. The concept is the same.

Jevons Paradox is a little different in that it doesn't change how we traditionally model the supply curve (that is probably why the two graphs on that Wikipedia page only show the demand curve). But the end result is the same that we have now moved to a different spot on the demand curve.

Yes, it's all about moving to a different place on the demand curve.

It's two things that regularly get missed with induced demand.

The first is the assumption of infinite demand. If two lanes isn't enough, and you add a third and that isn't enough, by induction (pun intended) you wouldn't have enough even with infinity lanes. But in practice it will be finite and might only be four.

The second is that you can "induce" demand by removing demand, and therefore reducing congestion and increasing demand. If your goal is to eliminate congestion then one way or another you have to satisfy the demand that exists without congestion.

Another blind spot is people using it as an reason/excuse for public transport. They somehow see a new lane as inducing demand, but not train tracks or a seat on a bus.

If more train lines or more bus seats increases the number of people using public transit, that's an unequivocal victory and is in fact the whole point of public transit.

Not if they go unused or underused, or otherwise end up being less efficient and/or more costly overall than the alternatives. Then it's worse of both worlds.

Theoretical efficiency and real-world efficiency are different things.

Public transit isn't inherently good by virtue of existing without real-world benefits. (To assume or believe it good without proof would be dogmatic faith, not science.) And those benefits gained need to be greater than any and all offsetting costs lost.

There are far more real-world scenarios where busses and trains end up being far less efficient than driving and flying than vice-versa.

The difference in logistical degrees of freedom between the two sets makes bus and rail far too reliant on ideal geographic and operating conditions.

Yet it's always these few ideal scenarios that are the basis for most cost and efficiency comparisons & claims, and are what get presented as justification for building/implementing.

And the countless public transport systems that never get the ridership or revenue that their pre-construction cost/benefit analysis or environmental impact statements predicted is proof that they rely on overly optimistic assumptions that rarely pan out.

By shifting the bottlenecks elsewhere, in the case of bandwidth. People would totally use way more download bandwidth, for videoconferencing / streaming if nothing else, but you run into latency and upload limits first, rendering the idea of nice 4k streams impractical.

That's what it is for everything, no? Something is "enough" when it moves the bottleneck somewhere else.

In the end it becomes humans. What's the resolution of your eyes? How many streams can you watch at once? It's less bandwidth than fiber has, isn't it?

For roads specifically, it's not necessarily suppressed demand. Commute times are a significant element in peoples' calculations about where to live. Increase road capacity and living further away (with cheaper land, bigger houses and so on) becomes more attractive, which adds to traffic on the road. The road capacity attracts the demand through second order effects.

It's not just suppressed demand, though. E.g. most people in big cities tends to measure commutes in unit of time rather than distance. Reduce congestion and the region considered commutable by people increases, and as a result the region becomes more desirable as a place to conduct business because you have access to a larger Labour pool.

It certainly is possible to outpace the increase, but the point remains that you need to consider that there likely will be an increase beyond any measurable suppressed demand.

It also matters because sometimes it points to alternative strategies: for roads it may turn out it is better to seek to induce demand elsewhere to alleviate congestion, for example.

One of my pet peeves, living in London, is that instead of alleviating congestion in the centre it'd be better to improve commutability between the town around the edge of London to draw demand out of the centre, for example. Another way of putting that is that to take advantage of induced demand, when capacity issues you should look for options to leverage it to spread the load whenever that is cheaper than increasing the capacity to the core of the system, and often spreading the load can be a lot cheaper.

In the roads case, the demand was always there. Increased capacity means that more demand is satisfied, even if the QoS for the satisfied demand went up.

Consider the person who lived close to work because commuting wasn't possible. With increased capacity, living elsewhere becomes an option. They wouldn't exercise that option unless they preferred it. That demand predates the availability of the option.

That's just the paradoxical thing about it though. With induced demand congestion doesn't improve so travel times don't improve, so there is the same (dis)benefit to moving as there was before and living elsewhere doesn't, or rather shouldn't, become an option.

Yet additional demand is still being satisfied, even if QoS returns to a certain equilibrium.

The problem is that the added capacity still isn't sufficient to satisfy the extant demand of people wanting to get to town.

I remember a time where I kept that DSL link saturated, because there was enough bandwidth to download anything I wanted, but it might take twelve hours. With fiber, I can download just about anything in seconds, and as a result I don't download anything until I actually need it.

Over-abundance has the upside that there is no need to over-consume, as there is in the case of a generous but still limited resource.

Of course, on the other hand, over-abundance easily leads to excessive waste, which is where metering plays a role. Even for a very cheap resource.

How long did that trend last, though? It sounds to me a bit like the way people who've grown up during a famine often keep heavily stocked food stores at all times. Barring industry-driven changes like video streaming and other content delivery mechanisms, I bet the average 18-year-old downloads far less today than the average 18-year-old a decade ago. Why download and store everything when you can just get it later if you need it?

(On the flip side it's always funny when driving with younger colleagues and they announce that the music might get choppy because mobile reception is patchy. I tend to explain in a Princess Bride grandpa voice about how once upon a time Spotify was called mp3s and it worked even without mobile data.)

1 word: greed

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