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Comment by vhiremath4 | Hacker News Reader

> In order to do it, they bored through mountains in Pennsylvania in order to make the path of the wire as straight as possible, reducing the distance information had to travel. In total, the project cost \$300 million. The result? They can send information in 13.3 milliseconds round trip, 3 milliseconds faster than the competition at the time. So we can see that a 3 millisecond edge is worth at least \$300 million.

I understand the motivation and rationale and that my take here is subjective, but I take a pause at how sad it is that we're literally boring holes through our natural mountains in order to flip bits 3ms faster in the name of high frequency trading.

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Exactly. Because it doesn't generate real value.

Lets compare to alternatives like dam and flood control infrastructure, better roads, rail, etc. I understand the real pragmatic benefits and return on investment from these. A farm field is irrigated, a home not destroyed, less fuel used in trucking, on and on. These investments generate real value because they increase the total of societal output, not just that particular factions slice of the pie. Meaning, you are finding new gold to mine, not just taking over part of your neighbors gold mine and saying you are adding value. Its not adding value to the overall economy.

Please help me, what real value does an investment like this yield for the economy as a whole? As i understand it an investment like taking part of your neighbors gold mine, not mining new ground.

Effectively they have increased their slice of the pie, in this case it is time not land, but not made the overall pie bigger.

It is interesting to think about things this way, in terms of investments that increase the carrying capacity of our economy, and those that don't.

Advertising comes to mind. The cola wars, while expensive, dont yield a net increase in cola drinking, just a relative difference between the brands. Same with beer, on and on.

>Please help me, what real value does an investment like this yield for the economy as a whole?

The argument usually goes like this: HFT firms provide liquidity for the market; they are usually the people on the other side of the trade when a retail investor buys stock/bonds/etc. So without the HFT firms, you wouldn't be able to trade at a good/fair price according to market conditions. Furthermore, if you buy stock from NASDAQ or NYSE or London stock exchange, you should get the same price. This idea that you should pay the same price for an asset regardless of where you buy it is enforced by HFT firms, as outlined in the article. Clearly, HFT firms need to get paid for this service, so retail investors typically pay the bid/ask spread.

Isn't the liquidity only worthwhile at times of low liquidity? The ability to quickly exchange shares only matters at times when you want to exchange shares quickly. The only time when you care about exchanging shares quickly is if the price is changing quickly. Those are exactly the times when HFT is the riskiest, and the most likely to be shut off to avoid losses. (For example, shutting off HFT as a response to the 2010 flash crash[0].)

I get the argument, but it feels like the societal benefit is taken away whenever it is needed, and paid for only when it isn't needed.

[0] https://en.wikipedia.org/wiki/2010_flash_crash

I don't think I get your point. Correct me if I'm wrong but it seems to be that you're suggesting that if I want to sell some of my shares, for example, that I should wait until volatility is low?

If I had a way of knowing when the market would have low volatility, I'd throw away the shares and become a billionaire trading options.

Saying you should wait for low volatility before trading is equivalent to saying you should wait until the price is high before selling. Both statements seem to reflect common sense but neither piece of advice can be translated into an actual strategy.

The impact of HFT market making isn't that difficult to observe - all markets which have attracted such participants have seen huge falls in spreads. The spread is a tax on everyone who buys and sells in the market so lower spreads are good for everyone. (For example the cost of buying and selling a DAX future before fees was about 70 euro just 15 years ago while the spread is now typically less than a euro.)

> Isn't the liquidity only worthwhile at times of low liquidity?

No, because liquidity is also about tighter spreads. Since the spread is effectively a transaction fee paid to buy or sell on exchanges, shrinking it is beneficial to most market participants.

Good point. Here is an in-depth analysis from the NY Fed: https://libertystreeteconomics.newyorkfed.org/2015/08/liquid...

I've never liked this explanation because most HFT is just front-running. The liquidity is there already, they're just shaving their cut off the top in most cases because they can move faster than everyone else.

I work in HFT and HFT is not front running. And no, the liquidity would not be there without HFT market makers

It's kind of weird that people have such strong opinions about things they know very little about.

Would you be so kind to explain to me in what way a HTF can provide "liquidity", especially liquidity that would not be there in the first place?

By the way, since the tremendous inflow of cash into index ETF, some stocks are bascially traded only by ETFs and HTF without many other market participants. I mean, what could possibly go wrong?

https://www.zerohedge.com/news/2017-04-09/horseman-global-un...

HFT market makers can quote tighter spreads because they take on less risk. They can take on less risk for some combination of two factors: their speed, and the accuracy of their trading models. Depending on the firm, a different trade off is taken, with some executing obvious strategies the fastest, and others operating at a relatively slow pace, but using much more complex and nuanced strategies. Since market makers quote orders on the book much more often than taking orders off the book (takers have to pay and makers get paid on almost all exchanges), they provide tons of liquidity.

For most securities, there are very few natural buyers and sellers of a security, so they would find it very hard to transact without an intermediary market maker.

All electronic market makers are HFTers compared to regular market participants, but they run a very diverse set of strategies, with some operating at much closer to human speeds when compared to the fastest of the bunch.

Market makers provide better price and execution than traditional human market makers, and are a net positive to the market ecosystem, at least in regards to retail investors (the institional traders do sometimes get fucked).

So before there was HFT there was no liquidity?

Much less, and it was more expensive. The total cost of market making has gone down substantially with HFT, mostly because a small firm replaces a large army of floor traders.

There were still market makers that provided liquidity. Algorithms can just do it faster than people.

I want so many people in these threads to travel back in time so that they can tut-tut the market makers for wearing lifts in their shoes.

I don't get it. Reminds me of a blog post were the guy discussed a Portuguese stock, construction industry if my memory does not fail me, that has a "very low" trading volume.

When I looked up the stock, (I think the stock was very expensive), trading volume was like 1 Share every 6 months or so. Yes, I guess you could call this "very low" trading volume. So where would HTF come in here?

An HFT would list buy and sell orders on the book so that if you wanted to buy or sell, you always could.

And cheaper

The market is already liquid and also more liquid.

Strategies that had less efficacy at $100mm position sizes now can scale to $10bn position sizes.

I like the growth of liquidity.

HFT is not front-running. Front-running is a form of trading on non-public information.

Some forms of HFT work by getting information from other exchanges before you, then front-running on price differences.

Front-running usually refers to a fairly specific scenario in which a brokerage or fiduciary executes orders as principal prior to dealing on behalf of their client so as to benefit from a market movement they anticipate will be caused by the client's orders.

This is categorically not what HFT firms are doing.

That's not what front-running is.

This is arbitrage, not front running. Front running requires not-public information.

Isn't the market more liquid if new prices come in every day rather than every week?

While this argument holds some merit for intermediaries in general, it provides no argument why boring a $300M hole in a mountain for a 3ms speed improvement adds any value.

There’s a relevant joke:

Two people on a hike see an obviously hungry mountain lion in the distance running towards them. One of them quickly starts changing his hiking shoes to running shoes; to which the other responds “do you really think these shoes will let you outrun the mountain lion?” To which the first responds: “I don’t need to outrun the mountain lion, I only need to outrun you”

Whether it’s 1ms or 1s makes no difference; for a class of strategies, any time advantage can tilt the average from “unprofitable” to “profitable” when you are faster than others - and the sums changing hands are huge (trillions notional or even thousands of trillions per day). A tiny advantage easily translates into a lot of money.

The people who bored the hole were paid a wage that allowed them to support their families. The company that made the boring machine received more capital to develop better machines. The company that made the fiber employed thousands of workers and engineers who are advancing the state of material science. The engineers who built the optics are furthering our ability to drive down the cost high speed data transmission. The provider operating the circuit is paying hundreds of employees and engineers who build out new infrastructure for other customers, universities, businesses. The HFT firm can now build a datacenter outside of the metro, freeing up land to house residents in the city. Banks can take advantage of the liquidity to reduce transaction risk and offer lower rates on financial products to customers. Customers who spend less on loans and credit have more money to spend on other things.

This process goes on, and on, and on. It’s why capitalism is so effective as an economic system. And also the reason why things that may not seem like they produce value actually produce extraordinary value for society.

By that argument, any kind of "make work", doing something pointless, provides value to society as a side effect.

For example: Consider a job going to the office to write on pieces of paper and then throw those pieces of paper into the incinerator so nobody will ever read what was written.

Sounds pointless. Is it "providing value"?

By your argument yes: All those people were paid and can now support their families. The paper makers made paper and advanced the state of the art in fine paper-making, as did the pen makers and the ink makers. The incinerator is looked after, and it keeps new incinerator designers in work. All the fuel which is mined to run the incinerator keeps miners busy. All the commuting to the office and back keeps train operators busy.

And yet, going to the office to write things on paper and then destroy them repeatedly does seem rather pointless.

It doesn't. These kinds of actions are entirely competition between HFT firms (the fastest ones get the biggest share of the pie). But the HFT firms as a whole do provide a service to the market, and at a much lower price than the alternatives, even with the apparently extravagent cost of these efforts (mainly because it requires a lot less people: old-school market making involved a lot of people on trading floors).

Honest naive question - Just because HFT firms provide liquidity does that mean it is the ONLY way such liquidity could be provided?

Market makers provide liquidity as a service. HFT firms are market makers: https://www.investopedia.com/terms/m/marketmaker.asp

Long before HFT firms, we had Market Makers -- they were often a separate department of the brokerage firm you were already using.

Therefore, Markets don't need HFT firms to provide this service, they simply coopted a friendly-sounding rationale in an attempt to dismiss skeptics.

"Market maker" refers to a "role" in a market. HFT is simply one way that role is fulfilled, in some markets (equities, futures, ...) but perhaps not others (corporate bonds, MBS, ...). No market needs HFTs to provide the service, but they exist because in those markets they provide a monumentally better (cheaper) service than their predecessors.

You don't need HFT, but those market makers lost to HFT on price. HFT is far far cheaper than the old market makers.

And we all benefit through lower bid/ask spreads

> Please help me, what real value does an investment like this yield for the economy as a whole?

I see this situation to be very similar to the reason why the Bitcoin network burns hundreds of MWh of power per day. They do this because it is the only way to ensure everyone adheres to the market rules that were collectively declared as "fair".

Bitcoins' fairness rules work by incentivizing an arms race of who can compute hashes faster. The "conventional" stock/bond/futures markets ensure fairness by resorting to time an order was placed as the ultimate arbiter when it comes to whose orders are filled first. In both cases, there is a physics-related element that cannot be cheated by any one market participant, because nobody can transfer information faster than light and nobody can produce power out of the void.

The end product of this is "fairness" - which is extremely valuable, because without a reliable ledger, bitcoins would have no value, and without the ultimate judge of time at the stock market, there would be no stock market, because nobody would trade at a market where a specific participant could just backdate his orders.

Of course the "fairness" is not directly a product of the 300m$ investment for that ultra fast data connection. Nor is it directly a product of the MWh of power burnt for bitcoin blockchain hashes. But these two things are direct outcomes of the rules that effectively produce the fairness we want, and without accepting that we get these outcomes, these rules would not function and would not be accepted, which would void them, because they can only produce the desired "fairness" product as long as they are accepted by the market participants. Hence I consider "fairness" to be an indirect product of these two effects - and all similarly-categorized effects that don't directly seem to serve any purpose except for being actions in some kind of arms race between market participants.

One could also replace "fairness" with "trust", if that's more to your liking. The concept is the important thing, not what the product is named.

> The end product of this is "fairness" - which is extremely valuable, because without a reliable ledger, bitcoins would have no value, and without the ultimate judge of time at the stock market, there would be no stock market, because nobody would trade at a market where a specific participant could just backdate his orders.

But again, those benefits are self-referential: Fairness rules for Bitcoin serve Bitcoin and fairness rules for stock exchanges serve stock exchanges. Would the wider world be very much worse off if we had no Bitcoin or stock exchanges?

> without the ultimate judge of time at the stock market, there would be no stock market

I'm also not sure about that. Yes, in principle, time is a good arbiter - however the descision to follow that rule down to microsecond precision seems like a deliberate choice to allow HFT. The article mentions front running as an attack on the trading system that would occur with inaccurate timekeeping. However, seems to me this could be circumvented: e.g., if an exchange wanted to ensure fairness but also prevent HFT (and the associated technology arms race), they could bucket orders by e.g. second resolution and then execute the orders in a bucket in random ordering. This will give predictable ordering at second resolution but would make front-running or racing impossible as the sub-second ordering would be unpredictable.

> But again, those benefits are self-referential: Fairness rules for Bitcoin serve Bitcoin and fairness rules for stock exchanges serve stock exchanges. Would the wider world be very much worse off if we had no Bitcoin or stock exchanges?

For Bitcoin? Not much. Probably we'd be better off, especially with regard to our climate. I can't see enough benefit across our entire society to offset the significant damages produced by burning all this energy into heat.

For stock exchanges? Oh yes, definitely. There's a huge bunch of research into the role of stock exchanges (and goods and futures exchanges as well, they work in a very similar way) in facilitating efficient trading of everything, from ownerships in corporations to goods and services. And there's definitely some undeniable truth to the argument that it is a good thing to have efficient trading of goods and services which is necessary for efficient production of stuff which in turn is necessary to fill our plates with food to eat, fill our medicine cabinets with antidotes to various ailments and so on and so on.

> they could bucket orders by e.g. second resolution and then execute the orders in a bucket in random ordering. This will give predictable ordering at second resolution but would make front-running or racing impossible as the sub-second ordering would be unpredictable.

In that case I as a broker who knows that one of my clients has just channeled a big, market-moving buy order of some stock through me to the exchange would simply inject a few hundred of smaller orders that buy the same stock, but with a low limit price that's slightly above the current price, but likely below the price the stock will be traded at after the big buy order has been executed. Statistically I will then get half of my orders executed before the big one hits, the other half of them will be ignored because the limit has been exceeded, which results in a nice, nearly risk-free profit for me. I could even try to put some sell orders in there with a sell limit slightly above the estimated price after execution of the big order in an attempt to sell the same stock that I just bought in the same batch that I got them.

Similar stuff can also be done without direct knowledge about some big order coming through, but just on the assumption of such orders being placed into the market by various participants due to external events. The game just moves from being one in which everyone tries to beat the clock into one in which everyone tries to predict the orders in the next "execution batch" and how to best generate your own orders to profit from that. Since that's still a race against time (there's a limited window of time in which you need to get your orders in) the entire aspect of getting your orders to the exchange quickly is still relevant, hence there will still be massive investments into that. It's just that in such a case, you add another aspect into which people can invest massively: compute power to perform as many statistical simulations of the next execution batches' contents as possible in as little time as possible. I guess such statistical prediction stuff is already being done by HFTs today, but due to there being no clearly delimited time window granted to the HFTs that would be large enough to do very complex simulations, I guess this complex statistical modeling is done on larger timescales, like to devise trading strategies over weeks, months or years, and the modeling that produces the orders that quickly react to sudden market events is probably pretty simple because it must be absurdly fast, producing results in microseconds.

So what you would get is something very much like the Bitcoin blockchain hash race, just not for something as trivial as hashes, but for the best possible advance simulation of the next "order block". Doesn't matter in the end, though, because both are embarrassingly parallel problems and thus can and will easily be blown up to consume as much energy and hardware as you can provide. The one thing that prevents this from happening in our current trading system is the continuity of the timescale - which is exactly what you'd like to eliminate!

Prices determine the allocation of resources in society. Higher prices of food in New York allow a dense city of 9 million to channel enough food from the economy to feed the populace. The more accurate the prices, the less waste (in terms of both the commodity and time).

While it may seem like any improvements to price-time reactivity would be negligible compared to the 300mm investment, these things are simply too difficult to measure in a complex system like a global economy where any change can result in a butterfly effect. Over many years, more reactive prices could prevent arbitrageurs (who perform a critical service) from making less efficient trades. In fact, the firm who commissioned the new line is likely doing arbitrage, which is one of the key services that allows us to have a globalized economy with relatively stable prices.

Ok, how exactly do HFT traders lead to less food waste?

The thing about complex systems is that you typically can't just say A causes B, which is what most people want. There is certainly a causal relationship, but it's a chain of events uncountably long, so it's best understood in terms of A improves prices and improved prices result in better resource allocation, as I tried to explain.

If you truly want to put in the work to understand how markets work, I'd recommend running a simple forex arbitrage bot with a trivial amount of money (there are plenty of open source options that are straightforward to set up and won't make or lose you much money) to see hands on. Also, check out Matt Levine's newsletters.

At first glace, it looks like it generated 300 million dollars in revenue for the construction, tunneling, and telecommunications industries. Which was a real value for the companies doing the work. Was the end result useful for anyone else? Probably not, but the companies and employees who made it possible took home a tangible value.

Exactly my point. It generated some work for a few companies, in the short term, but not ongoing value, work, equity for those companies or the economy as a whole.

But what about overall, total value to society, the economy, over the long term, not just to the few companies who won a bid.

OK, that's a fair point. The majority of the value was probably locked up in a small number of hands. I think some probably was spent on materials and services local to the project. Maybe some of the revenue went into expansion for some of the companies working on the contract? But besides being a one-off boondoggle, was there a net negative negative to the tunnel? Had the tunnel not been built then would that money would have stayed locked up in a single place? The money being spent on services and construction generated more economic activity than it sitting in a bank.

I dont think it's a two choice thing. The options aren't to keep the money in the bank vs build this specific tunnel. Its a bigger question, why not this vs. Other income producing infrastructure that has a longstanding, consistent return. Like a interstate highway improvement project.

This seems really close to the broken window fallacy. The kid breaking the window made some work for the glass maker and installer but the shop owner poorer. So on the whole the village is one window poorer.

I see where you're coming from. However that fallacy assumes that someone or something was injured and that there's a perverse incentive at play to incentivize destructive behavior. In this situation I'm not sure it applies. Who or what was injured by installing this tunnel? Were the tunneling companies now selling high-speed tunnels to other companies?

Fair enough. Though I imagine the ecological impact and carbon footprint is probably significant. We all live in a reasonably closed system, so the impact of every significant development touches us all.

If kids breaking windows is a societal problem, an economic system that has to frequently produce windows would result in stronger windows, making them less attractive for kids to break. A top down solution imposed by police, laws, and imprisonment also makes society poorer, arguably more so.

> an economic system that has to frequently produce windows would result in stronger windows, making them less attractive for kids to break.

If I just opened a new window factory, I'd absolutely be interested in as many windows breaking as possible, so I can sell more products. It would make a lot more economic sense for me to produce cheap, thin windows: I need less raw material to produce them and they will break more easily, giving me more opportunity to sell replacements.

>> Lets compare to alternatives like dam and flood control infrastructure, better roads, rail, etc.

I'm going to provide a totally contrarian viewpoint as an engineer previously employed by Wall Street -- the difference to the alternatives is simple -- one exists and the other is theoretical.

The difference is is that Wall Street pays actual paychecks to engineers to do these things. Meanwhile, as much as i'd love to work for a better railroad company or what not, I did not find any engineering jobs there (computer science and statistics in my case.) Jobs and paychecks is how I am able to make car payments and pay for my daughter's bicycle.

To continue the thought, if you really do feel dam and flood control infra is a better thing to spend money on (i feel this way), HN isnt really the place:

0. Be like Elon and start your own railroad and dam company

1. Invest your own money into a dam and infra startup

2. Lobby your senator and representative to put money into infra

Speaking down the folks who are actually giving engineers paychecks is not a great thing IMHO when there arent all that many alternatives. Same sentiment from most of my former colleagues with Physics PhDs on Wall St. Yeah, it sucks, but tell me that once you can land me a tenure track teaching position. Until then, let me eat.

> Please help me, what real value does an investment like this yield for the economy as a whole?

Think of it instead like parcel deliveries. It should be plainly clear that delivering a package in two days is more valuable than delivering a package in a week, that delivering a package overnight even moreso. Oftentimes, an item is only valuable if we receive it as soon as possible - if we had to wait a month to receive a package, the whole arrangement might not have been worth it in the first place.

Furthermore, it is also plainly clear that delivery is worth more for more valuable items. This is typically communicated in the price of insuring a shipment, but plain common sense explains why people are willing to pay hundreds of dollars in delivery charges for automobiles but not for a box of tissues.

If you understand that logistics is valuable, that speed makes logistics more valuable, and that logistics is made more valuable by the value of the goods transported by it, then it really should not be such a stretch of the imagination to understand how the logistics of capital plays by exactly the same rules; it is only a question of degree and scale.

Prices are information about the relationship between supply and demand, they allow people to make accurate judgments about resource allocation. This information is time sensitive so any decrease in latency increases the accuracy of the information.

Advertising absolutely generates value. An advertisement might sell someone a vacuum cleaner when they were previously using a broom, saving them countless hours every week to spend on other economic pursuits, resulting in a net benefit for society.

Advertising absolutely can generate value. An advertisement might sell someone magic beans that clean your house if you leave them under your kitchen table.

How do you know that advertising provides more value than it takes away?

Its just a business model.

You decided to understand tangible goods and decided not to understand ephemeral goods.

The value is no less real and the distinction is arbitrary.

The only thing happening here is an uncomfortable relationship with people making money and having complete discretion to acquire more goods and services with that money than others.

HFT has no more or less arbitrary value or merit than any ephemeral software business that you might happen to respect. SaaS, ad tech, data brokering, YC cash burning darling, etc.

Trying to rationalize its utility (“is it providing liquidity or just front running”) is just as much of a red herring.

Its just a business.

The question was “what real value does an investment like this yield for the economy as a whole?”

If I understand your comment correctly then your answer is essentially: it provide no value to society, but few other businesses do either.

To which I largely agree, and is the reason why myself and OP are left frustrated that society spends billions on things to improve arbitrary efficiencies while disregarding the well being of millions of people.

> it provide no value to society, but few other businesses do either.

That’s correct, this one happens to be more lucrative and scalable (revenue increases with capital size, overhead costs are logn) when it works.

Regarding a communication network that alters the terrain for the benefit of very few people, I can see that being frustrating. The business model typically does turn into licensing of the data route and others can benefit.

> Exactly. Because it doesn't generate real value.

Better price discovery generates some amount of 'real value', though.

Whether or not this particular investment generated 300 million dollars worth of real value is... A bit up in the air.

Isn't the main issue "financial products" (all these abstract things built over normal stocks)?

The modern economic concept of value is also largely subjective, so I don't think you need to caveat your thoughts with that.

As someone who used to write HFT code, I've vascillated between "it adds liquidity" and "it's a video game played between HFT firms". Neither is entirely satisfactory.

When I meet up with my old engineering friends, almost nobody is an engineer in the sense you might have thought when applying during the last year of high school.

Incentives are messed up. I remember getting offered £12K for a half year internship as an actual engineer. I took a marketing internship instead for a few grand more. My friend took an internship at Goldmans and was on £39K. When we got back, everyone applied to work in finance and consulting.

According to the market, making powerpoints is more valuable than making bridges, aircraft, medical equipment, etc.

We do somewhat envy the lady who took up an actual engineering job at a startup space launch company run by an eccentric South African guy.

Try not to think about the infrastructure dug and bored so we can make comments here. :)

This is the way of the world. How much cpu and gpu advancement is directly attributable to the simulation of shooting each other in the face?

On the flip side, how much more science is possible because entertainment dollars drive GPU development?

The technology trickles down to other spaces as a result of that investment. You could make the same argument about ARPANET only being funded because the government saw military command and control applications it (They weren’t funding it out of charity). Being able to move bits around 3ms faster is a VERY big deal for scientific research, medical technology, video delivery, defense, weather forecasting, and in so many other spaces that benefit humanity.

It would be a big deal if they had a wire you usually transmit at 6ms with, but they found a way of doing the same distance but 3ms. But no, they literally brute forced their way through a mountain to make the distance shorter, because they had the money to do it and want more.

Being able to spend money on a operation to make the cable distance shorter is hardly a very big deal for anyone else but nature and the company doing it.

What technological advancement? Is boring holes through a mountain somehow revolutionary technology?

It's also a sloppy way to put it. $300M is a fixed amount and should really be compared with the rate of profit resulting from this integrated over how long it lasts. It's a question of stocks and flows. An "edge" which is there every day (for a while) results in a rate of profit, not a fixed sum.

The edge is difficult to quantify, so I went with the 300M as a lower bound. IIRC, the company that made this line sold contracts for 300k/month to use it to around 30 companies. Source: Flash Boys book

My question is, how big is the hole? If it’s a trench style run of the fiber, this can managed in a very environmentally friendly fashion with little impact on existing environments as it were

On the other hand, if not managed correctly, I completely agree with you

This particular incident happened in 2009, when HFT was still relatively new and very profitable. These days, it's much more competitive and I doubt you could justify such an investment.

This is partly the cost of liquidity. Look at bitcoin for another example, On the order of $10 billion a year is spent on electricity to keep transactions secure.

When there is stuff that limits the path of price info there are wars and hunger and people die.

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