[HN Gopher] The high-frequency trading arms race: frequent batch...
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       The high-frequency trading arms race: frequent batch auctions
       (2015)
        
       Author : philips4350
       Score  : 83 points
       Date   : 2021-10-17 14:20 UTC (8 hours ago)
        
 (HTM) web link (academic.oup.com)
 (TXT) w3m dump (academic.oup.com)
        
       | twic wrote:
       | If you're a market maker, you really, really want to be able to
       | do low-latency trading in order to hedge fills before the market
       | moves against you. If market makers can't do this, they will make
       | worse markets - show less size and wider prices, or just get out
       | of the game. How do you do this under continuous batch auctions?
       | 
       | I have an underdeveloped idea that what we really need is limit
       | order types with built-in hedging. "Bid to buy 100 gizmos at 30c
       | each, and for every five gizmos bought, immediately offer to sell
       | 1 widget at $1.20; cancel this order if the best offer for
       | widgets moves below that price" sort of thing. Basically, you're
       | moving the simple reasoning that has to be executed at low
       | latency from the market maker's FPGA to the exchange's matching
       | engine.
       | 
       | Sometimes, you can do this by putting orders in spreads, but only
       | where a spread exists (or can be defined) for the two legs you
       | care about, in the right ratio.
       | 
       | You might also want to do more complicated things, like pulling
       | an order in one product if another product moves a lot, because
       | you think that presages a move in the product you're quoting.
       | 
       | The idea would be, firstly, to make it much easier to make
       | markets without having to invest in low-latency infrastructure,
       | broadening the base of participants who can do it, and secondly,
       | to reduce the negative impact of speed-blunting interventions
       | like continuous batch auctions or speed bumps.
        
         | Nevermark wrote:
         | So generalize simple market offers toward time-limited smart
         | contracts?
         | 
         | And everyone having the ability to do so at the same level.
         | 
         | Seems like a good idea to me, assuming contract constraints
         | that guarantee market resolution system will resolve quickly
         | and behave predictably.
         | 
         | And some nano-fees for contract execution to make DNS attacks
         | unprofitable (for the attacker, profitable for the market).
        
       | bob1029 wrote:
       | There are severe technological consequences for pushing for
       | synthetic discrete time. Exchanges that currently execute in a
       | serialized fashion may no longer be able to support the trading
       | volume if the underlying platform is unable to develop batch
       | sizes that naturally align with hardware capabilities and
       | timings.
       | 
       | Put differently, I think what is going to happen is you will
       | start stacking way more orders at each interval than you can
       | process before the next because the wonderful CPU pipelining
       | effects get wrecked each time you hit an arbitrary time slice
       | boundary. I suppose you could intentionally spin the CPU instead
       | of yielding back to the OS during these delays, but that means
       | you are not able to process any orders that are _currently_
       | arriving, so your tail ends up growing longer and longer.
        
         | atq2119 wrote:
         | I would be very worried if the machines actually executing
         | orders today were anywhere close to 100% load on average,
         | because of the well-known issue where tail latency explodes as
         | you get closer to 100% load. So I doubt the relevance of
         | everything you wrote there.
         | 
         | Batched auctions require different algorithms, sure. They may
         | even be more expensive to execute. I suppose you have to sort
         | the batch once instead of sorting as you go. _Maybe_ that makes
         | it O(n log n) instead of O(n)? Can you keep a traditional order
         | book up-to-date in O(1) per transaction? Either way, seems like
         | this should be a non-issue. Even if exchanges need to add more
         | shards for order processing, that 's just not a big deal.
        
         | zamadatix wrote:
         | Why would a premade queue be worse for pipelining than a random
         | queue which you also have to modify as you process on it? Seems
         | like a single pause per batch rather than constantly checking
         | if the work queue has something new put in it.
        
         | andylynch wrote:
         | This hasn't materialised as a problem (batch auctions are one
         | on the MiFID II venue models) - some eu venues have run this
         | model for around four years now, its definitely less widely
         | used than other models but has a niche.
        
           | twic wrote:
           | It might not have materialised as a problem because those
           | venues are not handling as much traffic as the busiest CLOBs
           | are.
        
       | akvadrako wrote:
       | Is there any mathematical proof that it's harder to game batch
       | auctions than what we have now?
       | 
       | For example, while other markets and the real world moves on, you
       | gain info. So the later in the batch you can submit a trade, the
       | greater your advantage.
        
         | aserafini wrote:
         | That was my initial thought as well: this would just become an
         | arms race to submit your trade last? But maybe if the trades
         | were priority queued it would negate that.
        
           | fighterpilot wrote:
           | Correct. I believe you need to randomize the auction time.
           | This massively reduces the speed advantage. Without that
           | speed is as important as ever.
           | 
           | How does a priority queue work?
        
             | akvadrako wrote:
             | That just leads to the same question: is there proof its
             | harder to game random batches?
        
           | harryh wrote:
           | _But maybe if the trades were priority queued it would negate
           | that._
           | 
           | If the trades are priority queued, then you have just
           | recreated the speed "arms race" that this idea hopes to
           | eliminate.
        
         | hcarlens wrote:
         | The ones that are currently live tend to have features that try
         | to negate this (randomised uncrossing times, price collars,
         | order priority based on arrival time or size)
        
       | dang wrote:
       | One small past thread:
       | 
       |  _The High-Frequency Trading Arms Race: Frequent Batch Auctions
       | as a Solution [pdf]_ -
       | https://news.ycombinator.com/item?id=20003222 - May 2019 (4
       | comments)
        
       | carterschonwald wrote:
       | While I was at jpmorgan I actually spent some time thinking about
       | alternative auction structures (vs the order book model). The
       | current trading model is ultimately a mechanization of the rules
       | from trading happened in a literal trading floor room, and a lot
       | of the structural issues stem from those rules treating time as
       | infinite resolution and the speed of information
       | propagation/light being instaneous.
       | 
       | There's some interesting details about how large trades are done
       | today that could perhaps be better reflected into some element of
       | auction design.
        
         | wolverine876 wrote:
         | So if we started with a clean slate, no trading room floor
         | history framing our perspectives, how could we do it?
        
           | carterschonwald wrote:
           | thats that billion/trillion dollar question :)
           | 
           | so I think theres a huge design space, and I think it
           | partially turns into a "mechanism design" challenge to
           | articulate a landscape of transaction / market auction
           | mechanisms that
           | 
           | 1) incentivize maximizing market liquidity
           | 
           | 2) recognize the speed of light is finite, and have that
           | inform the minimal time scale matching can happen on.
           | 
           | 3) obviate/remove the need to obscure large trades as a large
           | number of smaller trades (which is half the value of so
           | called algorithmic trading strategies to institutional
           | investors). This could be via having one design constraint on
           | auctions be that the market impact of the sum of the small
           | trades should be equivalent to the single large trade.
           | (ignoring the issue of the exogenous information of there was
           | a large trade ).
           | 
           | some interesting knock on consequences of these ideas are the
           | following
           | 
           | 1) the larger the time scale you're willing wait for the
           | trade to be matched to "the other side", the cheaper it
           | should be to trade! (creating liquidity is valuable!)
           | 
           | 2) if you're willing to allow your trade to be "partially
           | matched" instead of all or nothing, that too creates
           | liquidity.
           | 
           | the point being, you start with "what are all the
           | complications of how people do large/complicated trades today
           | that should just be trivial with the right auction" is sortah
           | my perspective. thats glossing over a lot of complexity and
           | other concerns, but those are some high notes.
           | 
           | that said,this is just the tip of the iceberg, and these sort
           | of market design questions are genuinely under studied in my
           | mind, and i could easily spend hours talking about this in
           | greater depth over coffee or such.
        
       | elzbardico wrote:
       | What is the benefit for society of allowing HFT? This is what we
       | should be asking ourselves.
        
         | H8crilA wrote:
         | ETFs only exist thanks to HFT
         | 
         | Have you ever wondered how is it possible that when you buy
         | some shares of SPY someone out there is somehow able to collect
         | 500 securities to fulfil your order? Even if it's not a literal
         | action-reaction, that is what must be happening at the margin.
         | 
         | Also, if you still don't believe me, then try to find out how
         | to unpack X amount of shares of SPY (for some non-small amount
         | of X) into individual securities. Can you do it yourself, for
         | example? Whom to call, where's the button for that, who can do
         | it?
        
         | kortilla wrote:
         | Better prices when you want to sell your stock
        
       | [deleted]
        
       | hcarlens wrote:
       | This type of order book is actually quite common in Europe now!
       | It provides an interesting alternative to central limit order
       | books and dark pools.
       | 
       | Around the introduction of MiFID II regulation in 2018, several
       | exchange operators added these frequent auction books.
       | 
       | Cboe's period auctions book is the biggest of these by volume:
       | https://www.cboe.com/europe/equities/trading/periodic_auctio...
       | 
       | In addition to Cboe, Turquoise, Goldman Sachs, UBS, Virtu and
       | Aquis also run frequent batch auction venues:
       | https://www.cboe.com/europe/equities/market_share/market/ven...
       | 
       | I actually co-wrote a paper about this at the time, and it's very
       | rare I get a chance to talk more about it! https://jot.pm-
       | research.com/content/13/3/5 (sadly it's paywalled)
        
         | kasey_junk wrote:
         | Periodic auctions still need tie breakers. CBOE for instance
         | falls back to size then time. This is the same tie breaker that
         | some CME futures contracts have used in a continuous order
         | book. Those contracts always had more gamesmanship than
         | standard price/time contracts when I was trading.
         | 
         | Has that become true in the auction space at well?
        
           | hcarlens wrote:
           | When they were first introduced, each of the fba books had
           | slightly different mechanics (matching priority, timing,
           | price determination), so each book needs a slightly different
           | approach. I guess you could see it as gamesmanship, but in
           | equity markets dealing with market mechanics properly is just
           | part of the job.
        
         | [deleted]
        
       | [deleted]
        
       | bob229 wrote:
       | Imagine all of the great minds that are wasting their time in the
       | financial services sector and understand why we are doomed as a
       | species
        
       | robocat wrote:
       | I thought part of the problem is that exchanges charge more for
       | faster access (e.g. physical collocation), so the exchanges
       | profitability depends in part on creating a bidding war between
       | HFT companies?
        
       | harryh wrote:
       | Probably worth appending 2015 to the title on HN.
        
       | secondcoming wrote:
       | The ad-tech world worked on a Vickery Auction for quite some
       | time. I've often wondered what things would look like if the
       | financial world worked that way instead.
       | 
       | (Vickery Auctions are pretty much dead now because websites saw
       | that bidders were bidding $X and automatically assumed that
       | because they weren't getting $X, but rather $(X - Y), they were
       | being ripped off)
        
       | chaps wrote:
       | Maybe someone can explain how it would work, but wouldn't this
       | need a wide price spread to cover risk?
        
       | kamaitachi wrote:
       | I was working in HFT as a dev team lead around the time of this
       | article (2105).
       | 
       | I remember this was being seriously considered by one of our
       | target exchanges (can't remember if it was Eurex or Globex).
       | 
       | Our main HFT trader didn't seem worried - he said that the race
       | would just change from a race to pick off an opportunity into a
       | race to align with any auction timeframe.
       | 
       | Back then, our strategies were implemented in FGPA so our
       | response to events could be timed very accurately. Even randomly-
       | timed rolling auctions wouldn't have posed any challenges.
       | 
       | Probably explains why this idea never ended up being implemented
       | by any of the major exchanges.
        
         | hcarlens wrote:
         | Actually, it got implemented by most major exchanges in Europe
         | in 2017/2018 and cboe seems to be bringing this to the US now:
         | https://www.cboe.com/us/equities/trading/offerings/periodic_...
        
           | kamaitachi wrote:
           | Wow - TIL. Thanks.
           | 
           | I've been out of the HFT business for a while, so i guess
           | things have moved on.
        
             | hcarlens wrote:
             | Haha yeah! Though times for these auctions are double-digit
             | milliseconds, a lifetime for your fpga strategies! And it's
             | still fairly niche, these are complementing CLOBs/dark
             | pools rather than replacing them. Where did you move to
             | from hft?
        
               | kamaitachi wrote:
               | Moved into a small company that does process control
               | (SCADA) systems development. Took a fairly large drop in
               | salary but the work/life balance improved and job
               | satisfaction increased.
               | 
               | I'd previously done a lot of work in embedded SCADA
               | systems (hence the fit for working with with FPGAs in
               | HFT).
               | 
               | I left mainly because I genuinely felt that there was a
               | certain futility with ultra low latency trading...it's
               | less about trading and more an arms race between quants
               | and techies of different companies, all with deep
               | pockets.
               | 
               | I guess embedded SCADA systems are my comfort blanket :-)
        
               | anonymouse008 wrote:
               | I'm merely an observer, but it feels, intuitively, that
               | HFT was great when things were fairly predictable -- or
               | more like the major indices and individual names moved a
               | most 2% on any given day -- and now, in the post-covid
               | era, starting with the DPZ spike, and you could argue the
               | TSLA original call buying spree, everything is in
               | shambles. A lot of HFTs I know of suffered serious
               | losses...
               | 
               | Could you explain, indirectly or without identifiers, why
               | now is different than back then?
        
               | ReggieCommaRose wrote:
               | I'm not sure about delta one firms but almost all the
               | options MM firms have been having record years in the
               | COVID / meme stock era.
               | 
               | In broad strokes, the things that hurt market makers the
               | most are long winded price trends and accumulation of
               | inventory. So generally MMs can and often will eat large
               | initial losses (depending on how many wings they happened
               | to have owned at the time) when huge volatility spikes
               | happen but when the raised volatility stays at that level
               | for some amount of time (you'll sometimes hear this
               | referred as market "regimes") and the MM was able to not
               | blow out from the initial spike they'll more than make up
               | their losses from the good trading environment after the
               | fact.
               | 
               | Market makers as a whole were suffering during the mid
               | 2010s when volatility was low year to year, correlation
               | with SPY was high, and all the indices basically just
               | went straight up every month.
        
         | amelius wrote:
         | If your strategies were implemented in FPGA, they were probably
         | not very complicated (considering the things you can do on a
         | regular CPU).
         | 
         | Wouldn't markets function better if every participant had a
         | reasonable amount of time to make decisions?
        
           | [deleted]
        
           | twic wrote:
           | The part of the strategy that lives on the FPGA has to be
           | fairly simple, but that doesn't have to be the only part of
           | the strategy. You can do all sorts of deep and meaningful
           | computation on a real computer, then export some settings for
           | a simple event-driven model to the FPGA, updated many times a
           | second.
        
           | tedunangst wrote:
           | As a retro computing enthusiast who does algo trading from my
           | Commodore 64, I would very much like more time to compute my
           | trades.
        
             | hansor wrote:
             | This is interesting. May I ask how do you do it from
             | software poinr of view? As for CPU and memory for sure it
             | is possible, but I'm more interested about how do you
             | connect into exechange/broker?
             | 
             | Contiki, SLIP, PPP, or maybe some ethernet expansion ?
        
             | twic wrote:
             | I'd love to read about you trying to persuade the exchange
             | to let you put that C64 in the colo.
        
           | tubby12345 wrote:
           | >they were probably not very complicated
           | 
           | They use linear models and soft cores. Plenty complicated for
           | the kind of arb you could get executing 500ns tick to trade
           | better than the next firm.
        
           | Traster wrote:
           | It's not always that straight forward. In the hft space
           | you're essentially always responding to 1 event, a trade, an
           | order, a cancellation etc. Events are generally spread far
           | enough apart that you can consider them independently
           | (obviously not always, but often) So it doesn't matter how
           | complicated your model is, if you can pose the question "what
           | would you do if X happened" to your model then you can
           | prepare your fpga with "if X happens do Y". As long as your
           | universe of possibilities is tractable (which it often is)
           | then an arbitrary model can have all latency sensitive events
           | offloaded to fpga.
        
         | im3w1l wrote:
         | The way I see it, HFT firms provide liquidity to the market,
         | which is good. They do so in an automatic fasion which makes it
         | cheaper than the past system of human traders. But they also do
         | a speed competition which is mostly wasteful. There may be some
         | benefit for the overall market of faster communications but it
         | is pretty low.
         | 
         | All systems have waste, some more and some less. This is
         | unavoidable. So the discussion might be more productive if it
         | was framed like this: Which system provides more benefits with
         | _less_ waste? Would frequent batch auctions lead to less
         | resources being spent on wasteful racing, and more resources
         | performing useful services for other market particpants?
         | 
         | Or if we zoom out even more, the two main purposes of the
         | market is allocating capital efficiently to businesses, and
         | redistributing money from the working population to retired
         | people (401k, IRA). And we can ask which market structure will
         | make it better at these tasks?
         | 
         | Framed like this it becomes natural to look at the other side
         | of equation. Instead of asking which structure would screw over
         | HFT's the most, we can ask which structure would be most
         | convinient for say index funds or other mutural funds. And
         | which structure would be most convinient for the individual
         | stock picker. We could even start to ask which structure would
         | help HFT's provide more liquidity with less risk.
        
           | HWR_14 wrote:
           | How do HFTs add valuable liquidity to the market? Does the
           | 500ns faster transaction time for a block of AMZN matter to
           | literally anyone? Other than the two sides of the trade who
           | lost some money to the HFT who MITM'd them.
        
             | harryh wrote:
             | When someone buys liquidity, they don't do so to close
             | their order 500ns faster. They do it to ensure they can
             | trade at the current market price because they don't want
             | to take the risk that the market will move away from them
             | while waiting for a counter-party to trade with.
             | 
             | Those that are comfortable taking this risk can simply
             | issue a LIMIT order instead of a MARKET order.
        
           | Retric wrote:
           | Swap to an auction batch model and they don't provide
           | liquidity, they simply don't have significant stakes relative
           | to the number of daily transactions. Essentially their an
           | outgrowth of all trades needing to be instantaneous which
           | lets them reuse the same capital thousands of times per day.
           | 
           | Add to that the fact HFT are profitable and they must
           | therefore provide negative economic value. Either the seller
           | or the buyer is failing to capture value.
        
             | twic wrote:
             | The idea is that HFTs provide value by tightening spreads.
             | 
             | The slower a market maker is, the more risk they take on
             | when they quote, because they are more likely to be caught
             | by market moves - less likely to cancel their quote when
             | the market starts moving, less likely to be able to hedge
             | if they get filled at the start of a move. To make up for
             | that risk, they have to earn more per trade. The only way
             | to do that is to quote a wider spread [1]. That means that
             | real money participants end up paying more when they cross
             | that spread.
             | 
             | The value captured by HFTs has not come from real money
             | participants, but from other, slower, market makers, and
             | they have shared that value with real money participants.
             | 
             | [1] Or to demand a bigger stipend, or steeper maker-taker
             | pricing, from the exchange, either of which means bigger
             | fees for other participants.
        
             | fighterpilot wrote:
             | Nonsense. Trade can be positive sum in utility to both
             | parties. One party making profits doesn't imply anything
             | about how utility is changing on the other side of the
             | trade. If you buy an iPhone, Apple have gotten richer but
             | you have also gained something (utility).
             | 
             | Your understanding of HFT is wrong as well. It's not all
             | low latency arbitrage. It's also execution finesse, risk
             | management and ML-heavy. HFT firms will still be extremely
             | active under this new market structure.
        
               | Retric wrote:
               | High turnover rates are part of the definition of high
               | frequency trading. If your holding positions for 30
               | minutes your not doing HFT. Ultimate buyers and sellers
               | aren't gaining anything on the timescales we are talking
               | about.
        
               | fighterpilot wrote:
               | I don't know why you're bringing this up because it's not
               | relevant, and nor is it accurate. You can have high
               | turnover rates in batch auction strategy as well as a
               | continuous trading strategy, this market structure change
               | won't change that. And you can have a HFT strat with low
               | turnover, e.g in a large tick name that barely moves
               | where you might get five latency sensitive trades per
               | day.
        
               | Retric wrote:
               | Latency sensitivity and Alo trading isn't the same thing
               | as HFT.
               | 
               | "Very short time-frames for establishing and liquidating
               | positions." strait from the SEC: https://www.sec.gov/mark
               | etstructure/research/hft_lit_review_...
               | 
               | Now it's true an individual stock may only see 5 trades
               | per day from a HFT algo, but theirs more than just one
               | stock. The larger pool of money sitting around waiting
               | for those 5 trades the lower your ROI. So, the obvious
               | strategy is to reuse the same pool of money to back
               | multiple different strategies.
        
               | fighterpilot wrote:
               | A HFT that's trading bond futures may only have a handful
               | of trades per day and hold for a long time because it's
               | hard to liquidate effectively. Sometimes they just range
               | all day.
               | 
               | Anyway my point is that it's wrong to think that HFT are
               | going out of business with this change because it's a
               | fundamental misunderstanding of HFT. There's almost
               | always an ML component and always an execution component
               | and these two skills are going to be critical to
               | profiting off the new market structure. Citadel, Jump,
               | Tower, you name it. I promise you they will be all over
               | this new structure.
        
               | Retric wrote:
               | > all over this new structure
               | 
               | I completely agree, and they are going to use the same
               | tools. The question is if this change is a net positive
               | trade for the economy, and that I don't know but I have
               | heard reasonable arguments in favor.
        
       | joshu wrote:
       | alternatively you could have one or more specific crossings once
       | a day and be done with the whole problem.
        
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       (page generated 2021-10-17 23:00 UTC)