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This Is What One Half Second of High Speed Trading Looks Like

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Re: This Is What One Half Second of High Speed Trading Looks Like

#111

Earlier quoted context omitted.

Complacent? Get in on HFT if you feel that it's making it unfair for human traders.

I'm speaking for the majority of people that can't afford racks of servers and custom-laid transatlantic fiberoptic lines. I'm speaking about typical americans that have their money in 401(k) accounts or maybe buy stocks from an online broker to try and fund their kids' college accounts. These people are all being scraped, very slowly but very surely, by HFT. That's the point I'm making. At least we all admit that th…

I'm speaking for the majority of people that can't afford racks of servers and custom-laid transatlantic fiberoptic lines. I'm speaking about typical americans that have their money in 401(k) accounts or maybe buy stocks from an online broker to try and fund their kids' college accounts.

Barriers to entry. Cost of business, etc... It's really not a concern to people who actually understand HFT and trade in their own way despite. They generally really don't mind the added liquidity.

These people are all being scraped, very slowly but very surely, by HFT. That's the point I'm making.

Buy in at $40. Sell at $80. Where does the computer scrape money from the transactions? It doesn't. Like I said, you're only losing if you're trying to trade like a computer. It's like trying to out-robot a robot on an assembly line.

At least we all admit that the modern stock market has absolutely no connection to the economy or to the interests of long-term investing or capital building. It's just a very large and very legal casino.

I disagree to the first part, and I think the second bit is an oversimplification.

It obviously matters, or else people wouldn't be upset by HFT or claim that they're losing money to it. We also have to consider the fact that pretty much all money comes through the bond and stock markets at exchanges. The exchanges are price arbitration centers for the economy. Paying attention to them matters because the exchanges and what happens there matters.

A casino is a place you go to lose money. It's all games and the odds are stacked against you. Everything we do in life is a gamble. An exchange is a place for people to make informed decisions about the prices of goods and financial instruments. Everyone loses and wins some.

I do relate to the long-term investing/capital building. The central banks keep printing money which funnels into the bond and stock markets. This in turn signals an abundance of actual economic capital, which there isn't. With the communication that there is plenty of excess capital for the long term, we (and especially people dealing in finance) act as if it is the case and start consuming capital. Eventually, facts catch up and we get some sort of terrible economic downturn. As a result of the long-term economic irregularity, actors act for the short-term because the long term is just too undependable.

Re: This Is What One Half Second of High Speed Trading Looks Like

#112
post #44

Earlier quoted context omitted.

None. This provides profit opportunities to those who will "heal" the price. Also, exchanges will revert back trades that happen over these flash crashes.

How long before someone (a hacker no doubt) games the system to create a selling spiral, just waiting to take profit of the rebound. If it´s well planned the one causing the dive is not going to be the one taking the profit (at least that it can be proved).

It will probably happen when one of the stock exchanges says "we won't revert fraudulent trades anymore". Until then, I kind of doubt it.

Re: This Is What One Half Second of High Speed Trading Looks Like

#113
post #106
post #69

Earlier quoted context omitted.

Never heard anyone arguing HFT is terrible because the trading floor died either. These are straw men constructs designed to paint HFT critics as luddites. I'm undecided about HFT's ability to provide liquidity in the market. There are certainly some drawbacks (e.g. you have to have high capitalization to afford HFT colocation), but there might be some tangible long-term benefits as well. But I'm more concerned about…

There have always been market makers. The fact that we've replaced a whole lot of market makers with a smaller number of people programming computers to act as market makers means that we're now probably devoting less human resources to this job. Also, as an aside, it's worth nothing that Hammerbacher only said that after making millions working at Facebook. I'm pretty sure that makes him an asshole.

There are ways of providing market makers without quite as much waste as the existing system of HFT. For example, instead of having the first trade order to arrive win, group them into generations of, say, one second, and execute them in a deterministic* order that does not depend on the time of submission (provided the trades arrived within the one-second window). You can still provide liquidity via automation, but you get rid of the latency arms race by providing a floor, below which improving reaction times doesn't win you anything.

* - For fairness, you could execute trades within a generation in a pseudorandom order determined by a random key, which is cryptographically committed to prior to the opening of trading, then reveal the key after the market closes to prove that you executed them in the correct order.

Re: This Is What One Half Second of High Speed Trading Looks Like

#114
post #106

Earlier quoted context omitted.

There have always been market makers. The fact that we've replaced a whole lot of market makers with a smaller number of people programming computers to act as market makers means that we're now probably devoting less human resources to this job. Also, as an aside, it's worth nothing that Hammerbacher only said that after making millions working at Facebook. I'm pretty sure that makes him an asshole.

There are ways of providing market makers without quite as much waste as the existing system of HFT. For example, instead of having the first trade order to arrive win, group them into generations of, say, one second, and execute them in a deterministic* order that does not depend on the time of submission (provided the trades arrived within the one-second window). You can still provide liquidity via automation, but…

There are some big problems with that plan. If I want to sell 100 shares, but I think that you also want to sell 100 shares but there is only 150 shares of demand then I'm incented to put in an order to sell 200 shares so that I capture 2/3rds of the demand.

But you're incented to do the same thing! So if you're going to put in an order for 200 maybe I should put in an order for 400? You can see where this is going...

People worry about HFT destabilizing the market. It seems to me that would be a much greater risk if you're incentivizing people to put in crazy orders that they don't actually want to do just to grab the percentage of demand that they desire.

Re: This Is What One Half Second of High Speed Trading Looks Like

#115
post #85

Earlier quoted context omitted.

> The question is: Does fast trading provide a net positive to society? Do web apps provide a net positive to society?

As opposed to what? We know that fast trading is being judged against non-fast trading. Are you asking us to judge webapps as opposed to non-web apps (for which anyone could give you a detailed response), or are you just trying to insult webapp developers?

> Are you asking us to judge webapps as opposed to non-web apps (for which anyone could give you a detailed response), or are you just trying to insult webapp developers?

I'm (I would have thought quite obviously) wondering aloud if everything we do needs to provide a net positive to society.

Re: This Is What One Half Second of High Speed Trading Looks Like

#116
post #114

Earlier quoted context omitted.

There are ways of providing market makers without quite as much waste as the existing system of HFT. For example, instead of having the first trade order to arrive win, group them into generations of, say, one second, and execute them in a deterministic* order that does not depend on the time of submission (provided the trades arrived within the one-second window). You can still provide liquidity via automation, but…

There are some big problems with that plan. If I want to sell 100 shares, but I think that you also want to sell 100 shares but there is only 150 shares of demand then I'm incented to put in an order to sell 200 shares so that I capture 2/3rds of the demand. But you're incented to do the same thing! So if you're going to put in an order for 200 maybe I should put in an order for 400? You can see where this is going..…

What happens if we aggregate both the supply and demand over a second (and don't allow price resolution smaller than a cent), then each seller gets to sell a portion of the demand proportional to the amount of this stock he owns?

This seems to disincentivize putting up for sale more than the seller wants to sell, and to also disincentivize "Sybil attacks" where the seller has an incentive to create false identities for himself. (Just a thought experiment, would be happy to know what I'm missing here :-)

Re: This Is What One Half Second of High Speed Trading Looks Like

#117

Earlier quoted context omitted.

Depends. It is mostly a zero sum game, so all told $0. Of course, some people make lots and some people make -lots.

While intraday trading as a whole is zero-sum, the HFTs are taking profits from other traders, not from each other. HFTs as a group are profitable.

A good amount of HFTs fail. I've heard numbers ranging from 70%-90% of new HFTs fail within their first 2 years. Very similar to startups when you think about it.

Also, HFTs are most definitely taking profits from each other. In fact, in a lot of cases the faster, more successful HFTs kill off the new ones to the market. Not to mention there are a good number of predatory HFTs who exist solely to game other HFTs

Re: This Is What One Half Second of High Speed Trading Looks Like

#118
post #21

Earlier quoted context omitted.

I don't see any comments here critiquing HFT simply because it's complicated. Rather, they seem related to whether it's actually a net-positive for society.

Every description of an HFT algo seems to fall into one of three categories: * Acting on public information, milliseconds before anybody else - which helps everybody else about as much as insider trading does. * Acting on trading information gleaned from "bid stuffing" (making and canceling orders really quickly) - which helps everybody else about as much as front running does. * Detecting the presence of large trade…

Would you rather have a person or a machine serve as the market maker?

If anything, HFTs have made it cheaper to trade. Because of the way exchanges are setup, the man in the middle will always be making a cut of the trades. Now though that cut is measured in pennies rather than what used to be often 1/2 dollar spreads.

Sure some of the predatory algorithmic trading serves no benefit to anyone, but you will always have people gaming/attacking the system if there's arbitrage potential.

Re: This Is What One Half Second of High Speed Trading Looks Like

#119
post #53

Earlier quoted context omitted.

The exchange could trade in rounds, e.g. permanent auction mode, where orders get matched only ever minute.

I believe that Taiwan (TSEC) does this, although I can't find a reference for it now.

I heard of that, too, but couldn't find a reference the last time I checked, either.

Re: This Is What One Half Second of High Speed Trading Looks Like

#120
post #53

Earlier quoted context omitted.

The exchange could trade in rounds, e.g. permanent auction mode, where orders get matched only ever minute.

What happens if there are more buy orders than sell at the same level (or vice versa)? Who gets priority on that fill?

Either first-come-first-serve, but that would give you some form of high-frequency again, or you just pro-rate them or fulfil them randomly.
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