Understanding Jane Street | Hacker News Reader

Understanding Jane Street

thediff.co

671 pointsmxtihvb374 comments

I find this stuff fascinating, and this article is way above average for online posts about proprietary/algorithmic/quantitative/low-latency trading (very leaky Venn diagram there). I have a few nitpicks but overall it's informative and it's an interesting format: viewing an industry through the lens of a particular firm, especially one as fascinating as Jane. Anything that develops literacy in modern finance amongst the lay public is a good thing in my book.

If this stuff floats your boat I'd also recommend any of Carl Cook's talks, e.g. https://www.youtube.com/watch?v=NH1Tta7purM. Optiver is AFAIK in a somewhat different business than Jane, but they're also players (or were last I had any inside baseball).

Too many people got their worldview on this industry from "Flash Boys", and I say this as a Lewis fan, is criminally stupid at best and in bad faith at worst (if you want a well-researched, accessible alternative: https://www.amazon.com/Trading-Speed-Light-Algorithms-Transf... is about a zillion times better).

It's a pretty short list of places I'd ever go through some grueling and semi-arbitrary gauntlet to work for, but Jane is on it for sure.

I hope the author(s) do Medallion next.

I hope the author(s) do Medallion next.

Medallion has probably gotten more scrutiny than any other fund, yet 3 decades later it's still as opaque as ever beyond vague 'statistical methods'. It makes a lot of money no matter what. It's more tight-lipped and exclusive than Jane Street. I don't even think anyone knows even if it's doing market making or not. Or if it's making short-term directional bets. You would think after 30 years stuff would leak and the edge would be gone. Employees are paid enough to not disclose, and likely are divulged only a small part of the overall method/system, so only a handful of employees will know how it works in its entirety. What it's doing has to be on a very large scale and in a big and liquid market to be so consistent and profitable.

Oh yeah, RenTech is just fascinating, and the opacity only lends to the mystique around it. People are talking a lot about how hard it is to get a gig at Jane, and AFAIK it's fucking hard, but one of the best mathematicians who was also a super-hacker I've ever met crushed the Jane interview and got bounced out in the RenTech screen.

Of course, the 30%+ annual returns almost every year for 30 years doesn't hurt the mystique either ;)

It's interesting that their other funds are far more mundane in terms of performance and last I heard Medallion can't hold much capital (~10B or so I've heard in whispers), but there is definitely something interesting as hell going on there.

Near as I can tell it's the hardest job to get on Earth. Rumor mill is that they pre-screen candidate based on their citation record in the literature, though that's obviously hearsay and I don't know if it's true.

Had "The Man Who Solved The Market: How Jim Simons Launched The Quant Revolution" on my shelf for several years as an out-of-the-blue birthday present but I finally got around to reading it earlier this year and I'd absolutely recommend it.

The emphasis on published work rang a bell, but thumbing through the book I can't find it off hand.

I enthusiastically second "The Man Who Solved The Market".

I also enjoyed the book and tried to find out more which I wrote about here (in my non-monetized blog): https://sileret.com/blog/renaissance_technologies/

In addition to RenTech, TGS is another intriguing place that mostly flies under the radar and from all rumors seems to have been fantastically successful over 3 decades. It’d be very interesting to hear about other less known firms with stellar, albeit likely smaller in absolute terms, levels of success.

TGS is just weird. Friend of mine making very good money at staff level had them reach out to get him to come interview, saying they would at least double his comp.

Another friend at G said the “smartest person in the office was poached by this company TGS, have you heard of them?”

I would recommend the book The Man Who Solved the Market about Medallion founder Jim Simons. It doesn't go over the strategy extensively but goes through the history and culture of the firm. From reading it I would attribute their performance to execution. They have an incredible pipeline and hire almost entirely engineers and scientists. They have a rigorous scientific method in finding and executing on signals. And they've resisted taking more money and earning more on the management fee, opting for performance.

Everything about them is boring. They're well paid sure, but they're based in long island and hire mostly grey beards and don't overhire. Compare that to Jane Street hiring interns jumping through silly hoops like betting poker chips on puzzles. It's a bit of a farce.

Theoretically other firms could copy this, but the main goal of a hedge fund manager is keeping AUM. High AUM and poor performance is better than low AUM and strong performance. So its a lot easier to optimize on maximizing AUM and managing your brand. There aren't a lot of mathematicians that start hedge funds so the people starting them already seed the company with the wrong culture to replicate RenTech.

It's probably pretty easy to keep the returns on a pot as small as $10bn sweet if you just reserve all your best alphas for that fund. There are proprietary trading firms trading pots that size for a single shareholder.

What I've been told is that Rentech also effectively use their public funds as a source of revenue to juice development of proprietary platform, so some of it is business cunning rather than a hard technical edge.

They were also got on the quant train very early.

To even have those ‘best alphas’ in the first place and then select them in advance for your best fund is the impressive part. The returns are insane even if the fund is capped.

They were successful long before they had those public funds though.

RenTech is also a bit different than Jane Street. While smart people no doubt work at Jane Street, some very serious brains have worked at RenTech and contributed to Medallion, people like Elwyn Berlekamp.

+1 to Trading at the Speed of Light. A great read, particularly for any engineer curious about clinging to the limits of physics. An example: microwave towers are used to beam data from Chicago to New York because it's faster than fiber optic cables. Even crazier: these microwave towers have their repeater hardware at the top of the tower (microwave towers usually have it at the bottom) so that they don't lose time in wires going from the top to the bottom.

Even microwave is slow, they are using shortwave radio for certain signals. Maybe neutrinos are next?

https://sniperinmahwah.wordpress.com/2018/05/07/shortwave-tr...

I'm not sure what's going on with this comment so let me make three observations:

The speed (latency) of the EM spectrum is the effective celerity of the medium: this doesn't differ in the air between microwave and shortwave in any meaningful way.

The speed (throughput) achievable on a given frequency is limited by the period of that frequence, high wavelengths can modulate more signal. Microwaves are higher frequency than radio by definition, so they have a higher throughput.

Neutrinos don't exceed the speed of light, and make a very bad medium of transmission given the near-complete lack of interaction with baryonic matter.

Shortwave radio can be transmitted around the curve of Earth by ionospheric reflection and refraction so fewer repeaters are needed. This allows crossing vast oceans where microwave infrastructure might not be possible.

As you say the downside is available bandwidth and throughput.

Another good point, and one I thought about before replying, but that doesn't make microwaves slower, it makes them inapplicable.

That’s why most markets close during night time.

Neutrinos don’t need to go around the earth, so in theory you have a pi/2 advantage over an EM signal when sending to an antipodal location, for instance. In practice of course, throughput is utterly horrible for the reason you indicate.

Latency would also be degraded by the interaction property. The probability that you detect the first packet of neutrinos is extremely low.

All you need is a couple bits, but yeah, making sure it’s the neutrino your buddy sent and not some other one is where it gets complicated.

This assumes that neutrinos aren't slowed by a dense medium as light is.

That's a maybe. Still, good point.

The game is repeaters and path lengths, not the speed of the medium itself

A 2019 article on the various companies competing for this [0]

0. https://www.bloomberg.com/news/features/2019-03-08/the-gazil...

Since this is Hacker News, let's not beat about the bush. Here's a channel that actually go through derivatives pricing without hiding the math:

https://youtube.com/c/QuantPy/videos

Whenever the topic comes up, I throw out a reference to Hull's Futures, Options and other derivatives, Wilmott's Quantitative Finance, and possibly also Taleb's Dynamic Hedging.

That's more than enough on the instrument math side, most of what you'll see is pretty mundane stuff, unless you end up on an exotics structuring desk.

I'd also note that JS and other MMs mostly don't do anything requiring you to know the intimate details of these things, a lot of it is understanding how the market works rather than the deep instrument math. That might mean other kinds of math of course.

My writeup: https://keithalewis.github.io/math/um.html for modeling and https://keithalewis.github.io/math/uf.html on now to more accurately reflect the real world. I have taught Derivative Securities at NYU, Columbia, Cornell, and Rutgers over the past 14 years, but my day job is turning math into software that produces numbers people running a business will pay for. The textbooks are missing some important things.

Nicely organized and dense.

Thanks for the material!

Hull's Futures, Options and other derivatives was on the bookshelf of a friend who worked at JS - it was their bible.

I always throught market microstructure was more important, but they insisted a disciplined application of the maths (as per the bible of Hull) was where the magic really was.

If you come from a pure math theory first background I would advise starting out with Björks “Arbitrage theory in continuous time”, I personally found the lack of rigor and superfluous examples in Hull frustrating and found Björk much more approachable then you can look into Hull for real life practicalities like daycount conventions, etc. If you want to go into complex derivatives pricing I would advise looking at the Andersen and Piterbarg trilogy.

I would also suggest to forget about Hull and Wilmott and would suggest to start with the excellent book by Shreve: "Stochastic Calculus for Finance. Volume II: Continuous Time Models".

Then, you can quickly read Bjoerk, work through Brigo/Mercurio (if you like that style) or Andersen/Piterbarg. Alternatively, if you want to fully dive into into the subject after Shreve, Musiela/Rutkowski: "Martingale Methods in Financial Modelling" is wonderful.

I'd say that Shreve and Musiela lack rigour and are too focused on trivia, name-dropping and anecdotes. Jiao's "Infinite-dimensional methods in amassing vast bags of gold" is unsurpassed. For its coverage of Black-Scholes, I'd also recommend Schulz's "Good Grief, Charlie Brown". Sorry, everyone seemed to be doing this so I felt I should contribute too.

I honestly can't tell exactly when the thread meandered into satire.

This. Exactly this.

Thank you kindly for what looks like a great resource!

I've been trying to put myself through YouTube night school on some of this stuff, and MIT OCW has great resources as well at significantly less cost than going to MIT ;)

This is a pretty reasonable jumping off point for their corpus of financial engineering stuff: https://www.youtube.com/watch?v=HdHlfiOAJyE.

I'm fortunate enough to work with a person who actually understands derivatives trades with some sophistication, but that's a happy accident and the more people have access to good online resources the better!

Edit: I forgot to mention this book (https://www.amazon.com/Algorithmic-Trading-DMA-introduction-...) in the spirit of something more technical than the general-audience one I linked above. I have some nitpicks with it as well, but I've gotten value out of it.

Followed quantpy tutorials to implement my own black scholes and heston pricing models last year. Highly recommend.

Michael Lewis is a great writer, but the closer you are to the subject the more his shortcomings are exposed. I felt the same way about The Big Short and to some extent Liar’s Poker. He has an annoying tendency to assume that if he doesn’t understand something, either it’s completely inscrutable to everyone or simply BS.

(And to pile on, The Blind Side was the touching story of how Lewis’s prep school classmate, an Ole Miss booster, gamed the system to provide improper benefits to a high school recruit.)

Liar's Poker was autobiographical, though. He should have got that right :-)

While I agree that Flash Boys was below par, what's wrong with The Big Short? I thought that was well done, accessible, and largely accurate.

I think it's probably because I was there for it. His construction of the narrative, while better than many (including many straight journalists) ends up sort of falsely casting people into hero/fool/villain roles that make the book work as an entertainment, but don't fully hold up.

It's a decent book, and a decent movie (kudos for one particular scene where I recognized data from the actual LoanPerformance database) I actually prefer the movie Margin Call for more accurately capturing the feel of the crisis from inside a bank.

But wasn't the point of the Big Short to show the perspective of people "outside" the mainstream who made big bets against the system/banks? Not surprising then that it didn't really show what was happening in the banks themselves.

No, the book is very different from the movie, I'd say it's almost the opposite in that it was mostly narrated from the perspective of the banks.

Another compounding factor is people often assume the message is "banks bad" but it's more "oh this system was so complex that any one individual did not understand the impact of their decision(s), much much more than everyone/anyone was playing super fast and loose from their particular perspective "

I liked The Big Short.

On a different but related note, I also really enjoyed the Compleat Ubernerd, written by Tanta, all about mortgage servicing in the mid 2000s: https://www.calculatedriskblog.com/2007/07/compleat-ubernerd...

I'm not sure how it has aged (no Dodd-Frank updates, the author has passed away) but it was glorious in its time.

Tanta was the ABSOLUTE BEST writing on the financial crisis as it was happening. You've made it when Federal Reserve Bank of NY cites your blog in a footnote in their research report.

https://www.newyorkfed.org/medialibrary/media/research/staff...

The CR blog was not the same after she passed away.

Agreed, Calculated Risk was required reading at the time. So much insight.

(On Tanta's passing: https://www.calculatedriskblog.com/2008/11/sad-news-tanta-pa...)

Having worked as a quant GS on HFT, +1 on Flash Boys being criminally stupid at best and bad faith at worst.

The Diff is easily one of the best value’s I get despite being >$200/year. I’m not sure how I’d rank it relative to Stratechery, I personally enjoy The Diff more but Stratechery is more relevant to my work and is also excellent. Byrne churns out an all-timer like this every other month or so, and his average posts still consistently include the best sentences I read of the day. It’s one of the only newsletters that, if I get behind on reading it, I make sure I catch up on every missed issue.

> It's a pretty short list of places I'd ever go through some grueling and semi-arbitrary gauntlet to work for, but Jane is on it for sure.

It certainly seems like an interesting place to work, but I find their hiring process as a bit of a red flag. Places that hire like that confuse me, because it seems it's going to apply a very selective filter to applicants that make it through. And I don't meant selective in the sense of technical ability but more emotional, social, and thinking styles. I get incredibly nervous in technical interviews and with a wide background, I don't always know certain bits of computer science. So, I do terrible in these style of interviews, because they do nothing to expose what I do know or how I really think on projects.

As another point of why I don't think they work, they almost are never two-way. And if they were, it would show the pointlessness of them. If I asked interviewers a bunch of questions about things that I know about, then we'd just be trading blows, which is pointless.

> I find their hiring process as a bit of a red flag

This is a bit like saying you find the hiring process at the NFL or for SEAL teams a red flag. You either fall through the selection sieve or you don't, that's the whole point. The filter has served its purpose, and they end up with the elite high-performing teams they desire. There's nothing wrong with you or the filter if you don't make it. The filter clearly does work because Jane St prints cash like the Fed and is one of the top MM firms out there.

I understand the perspective, although it's different and not really comparable to those other things you mentioned, especially since the NFL and the SEAL teams do not evaluate people solely based upon a few hours of tunnel-visioned interviews. They are primarily evaluated on their performance in real-life scenarios and training across a decent amount of time.

Of course Jane Street is successful! There's no question there. However, I don't think it's much of a question that they probably miss out on some great candidates that don't fit into that type of hiring process. It's possible they view those as acceptable losses.

The author is Byrne Hobart: https://twitter.com/ByrneHobart and his substack The Diff is just generally great.

I find the article to be a poorly written piece of propaganda for Jane Street as you could change "Jane Street" for "Citadel" for example and entire paragraphs would still be true.

> it's an interesting format: viewing an industry through the lens of a particular firm

What's interesting about that? Almost every other article does that.

>the winners get a job from which people routinely retire rich in their 30s, and the losers... don't

Honestly, I find this ridiculous. Firstly, Yes, working at Jane Street is a well paying job and you'll do well out of it. No. People aren't routinely retiring in their 30s. I don't understand where this absurd idea comes from. Look at all the rich people in the world, look at how old they are, and ask, are they retired? No! People who are driven and smart don't suddenly earn their first $5m go off and buy an annuity. They're more likely to go off and found their own trading shop at 30 than they are to retire.

Secondly, you know what happens to people who don't get hired after their internship at Jane Street? They go to HRT, to G Research, to Jump, to Citadel, to Optiver, to IMC, to XTX, if they're really unsuccessful they'll go to Google, Microsoft, Amazon, Meta. These are not people desperate for a job.

I think the author meant "could retire very comfortably in their 30s", and you're correct to point out that's not what it literally says.

But as for "could"? Shit you can do that at Google, Microsoft, Amazon, Meta if you're in that league and start out of undergrad. In my experience (more than a few of my FAANG-era colleagues either came from or went to high-technology finance), people don't actually leave Google to go to Jane for the money (which is similar at the p99), if you're a baller willing to pull the hours you can make many millions a year in either place.

I think people go to high-technology finance because they want to test themselves against a harder class of problem in a more adversarial setting against people who feel the same.

That's anecdotal, but my sample size is more than two or three.

> I think people go to high-technology finance because they want to test themselves against a harder class of problem in a more adversarial setting against people who feel the same.

Maybe this is so at other finance firms, but my experience with developers who go to Jane Street is quite different. Because Jane Street heavily advertises OCaml as part of its recruiting strategy, I know many people who ended up there just because they wanted to program in OCaml while still getting FAANG comparable salaries. They don't care at all about finance (at least initially, maybe it becomes an acquired taste for some).

Allegedly they use it because it's "readable" by both tech and traders. I don't really buy that; I think the real reason is that one of the founders used it because they liked it, and now they have all this legacy stuff laying around that's too expensive/time consuming/risky to replace. I hear TGS is stuck with their Fortran stack precisely for this reason.

Having worked in HFT for well over a decade now, I'd say OCaml is more of a deterrent than helps in getting access to larger pool of talent.

Esoteric languages is often a good screener for good devs.

A large talent pool isn't necessarily a positive if you don't spend a lot of effort on your recruiting (mostly filtering) process. It really just increases the risk of bad hires.

This. If you want really good devs, they tend to play around with all sorts of things that don't necessarily have economical value. This includes esoteric programming languages.

I'm struggling to understand how OCaml reduces the risk of bad hires and other languages don't.

That makes sense to me. But, in light of that, the ones who do go to Jane Street are relatively more likely to be interested in their tech stack and OCaml, as opposed to wanting to "test themselves" in the "adversarial setting" that the post I quoted describes. In contrast, the couple of people I know who went to HRT or Jump Street are much more like that description. They deliberately targeted HFT work, whereas Jane Street has more people who "fell into it" because of this outside interest.

I mean, Yaron used to go around a lot and give guest lectures about OCaml programming "in industry" at all sorts of functional programming courses in universities. I have to imagine they thereby recruited people who would have never considered HFT shops otherwise.

Jane Street recruits silly hard from Cornell’s CS dept because part of our required curriculum is functional programming w OCaml. They definitely introduce a lot of math/cs kids to the idea that finance can be a meaningful technical challenge instead of just Dyson bros in spreadsheets.

Then again I think one of the founders or top execs is an alum, so it’s possible Cornell has that course in that language because of Jane Street

A larger talent pool isn't always better.

Every few months or so I run out of patience with C++ and wonder about the alternatives, of which there seem to be very few in HFT. Jane Street stands out for that reason. It's a smaller talent pool but I don't think it's a subset of those that the C++ shops can attract.

> I think people go to high-technology finance because they want to test themselves against a harder class of problem in a more adversarial setting against people who feel the same.

That and among developers, I think Jane Street has hit "mythological status". I've known about Jane Street since I was an undergrad looking for internships and it was always talked about like: "oh yeah, that's where the REALLY smart people go to work". I think a little part of going to work there for everyone is figuratively one-upping your friends from college, you made to the place where geniuses worked.

> But as for "could"? Shit you can do that at Google, Microsoft, Amazon, Meta

Yes, these are some of the highest paying companies on the planet. Your statement is not a put-down of Jane Street.

Oh just to clarify, it was not my intention to put down Jane in the slightest. It's a fascinating firm in a fascinating field that is obviously full of elite mathematicians and technologists. I'd most likely be willing to work there.

> People who are driven and smart don't suddenly earn their first $5m go off and buy an annuity

I guess I must not be driven, because I would. Or at least something close enough to that. $5m just earning interest at 5%ish is way more income than I need to live the lifestyle I want.

I'd buy a few acres in the middle of no where, build a nice house, grow a big garden, raise my daughter as a nice family man and never work again.

Obligatory "Office Space" scene on "what would you do with a million dollars": https://youtu.be/4lmW2tZP2kU

The thing is, if you end up in a job that pays this well it’s because you’re either very lucky (and congrats to you) or you’re very passionate. If you’re in the latter category why would you retire when you’re being paid to do what you love?

> it’s because you’re either very lucky (and congrats to you) or you’re very passionate.

It's never because you're very passionate. Passion has basically no correlation with financial success. Millions of passionate artists, musicians, writers, and all of them broke as can be, most working shit jobs to pay the bills wishing they could just be passionate and make money from that. Passion is bullshit.

The real path to financial success is a combination of: being born to parents with the means and motivation to see you well education; being born lucky enough to be a little bit clever; being lucky to pick a career that makes a lot of money, often only by ignoring idiots who say 'follow your passion; putting in a lot of hard work to get good at something that is in-demand.

Or the usual answer: just being born wealthy and wouldn't-you-know-it you wound up wealthy too.

> Passion has basically no correlation with financial success.

Have you got any evidence for this? I would expect that passion correlates with hard work, and hard work seems to be necessary for success. I agree that many artists are passionate, but surely people can also be passionate about doing things like writing software or other activities that are valued highly in the market.

Do you have any evidence that it does?

We live in a culture that wishes passion lead to success. It's what we're taught as children here. It's what we want to be true.

And yet I find no strong evidence anywhere supporting the assertion that it does; just people claiming that it's up to those who doubt to disprove it.

Passion is a fairy tale adults tell each other because it's nicer than the reality that dumb luck and being born wealthy are the only real chances we have.

And those who were lucky or born on third base love to tell everyone it was because they were just so darned passionate.

i think extreme tails of "success distribution" gives a distort impression of odds.

Passions change. Also, I'd guess most CS grads going to work for JS aren't passionate about stock trading/market arbitrage - they're passionate about the pay or maybe OCaml, but the actual thing that JS does, probably not - it seems hard to be passionate about in and of itself (would someone work there for free because they were having so much fun?). And even if someone might be initially, they likely won't be after 5 years and enough money to retire on comfortably.

This isn’t true. It’s most likely because you went to an Ivy League school

Hence lucky to have been born to wealthy parents.

“ Look at all the rich people in the world, look at how old they are, and ask, are they retired? No! People who are driven and smart don't suddenly earn their first $5m go off and buy an annuity.”

No but having the freedom to start your own trading shop (or company) is hugely different than having to stick with a job you mostly don’t like to pay the bills

> Look at all the rich people in the world, look at how old they are, and ask, are they retired? No! People who are driven and smart don't suddenly earn their first $5m go off and buy an annuity. They're more likely to go off and found their own trading shop at 30 than they are to retire.

This kind of debate needs to be backed up by numbers or it won't be very productive. To get started we should know the percentage of millionaires in their 30s who are still working, and the ones who aren't working but are looking for a job.

Personally I can think of several things I would do with $5m other than buying an annuity. If you have that kind of money you are basically set for life if you make a few right choices.

Yes, all depends on how you spend your money. $5m will get you something decent in Manhattan, but you could live like a King somewhere else. I have a friend that retired off just over $1m as he moved back to his small hometown. House cost $30k, drives the same car for 15 years, lives frugally.

If you live in a place where a house costs $30k and on top of that you live frugally, you can probably retire with half of that already.

What would you do with $5m?

It is possible that people who chose to retire after they feel they have enough people to do it, would not be noticeably visible. Why spend time covering a guy who has retired and living a quiet life?

I think there is also a big question of what sort of spending habits these people have acquired. Their peers are making lot of money. And I doubt everyone is extremely frugal. Margin Call I think gave pretty good example how some in other firms might be spending their income.

Stepping down and just starting to live on annuity might not fit to what they have come to expect.

The relevant scene: https://youtu.be/xW1CrQu_H6E

Great film.

The culture of HFT (CS/JS/CHI.*/Optiver/IMC) is not 80/90/2000’s IB.

It's very, very common for rank and file prop traders to retire in their 30s. Some are ambitious and start their own firm or keep doing it, but many decide $10m/$50m/whatever is enough and leave the industry. They likely got into it just to make money, not because they loved it, so once you have enough, why keep going?

Generally good article that delves into how a market maker functions. Couple points:

Re EA: quoting my boss, EA isn't really a dominant thing in the market maker space, it's pretty much only espoused by a couple high profile individuals (mainly, SBF).

Re strategy: point about how there's little strategy involved in being a market maker is off-base. Everything is ultimately strategy: do I continue to pour resources into a strategy that is losing money in the hopes of eventually seeing pnl? What markets should I focus on? What is the best use of time for each employee that maximizes pnl/head? etc etc

One thing that I thought article got right is that most work involved in market making is about avoiding trades, not making them. Capturing the bid ask spread is conceptually easy. The hard part is avoiding trading with toxic counterparties.

Part about put options is especially apt. Market making during a crash / recession (like right now) is especially difficult because all the non-toxic counterparties have stopped trading as much (people like to trade a lot more during a bull market than a bear one). By setting up a structure such that you profit during a crash (either by buying puts, leaning net short, or through some other method), you introduce an uncorrelated return stream that can really help.

> EA isn't really a dominant thing in the market maker space

The article doesn't say it's dominant, it says "There is a weirdly high overlap between quant finance and Effective Altruism in general, and between Jane Street and EA in particular (it is emphatically not 100%)"

I know quite a few EAs who work or worked at Jane Street, much lower profile than SBF. What the article misses is that a lot of EAs specifically went into finance because if you're looking to earn money to donate it's one of the places you can earn the most, and not because of "where they advertise jobs" or "overlap in outlooks".

Does a market maker consider another market maker “toxic” by your definition? I assume by “toxic” you mean too smart? Or do you mean they cheat?

"Order flow toxicity is the measure of a trader's exposure to the risk that counterparties possess private information or other informational advantages."

Usually, flow from other MMs isn't toxic.

Toxic flow can also just be someone who's executing a very large order, even if that counterparty isn't informed. If you fill them as they are starting to work their order, you could get run over as they continue to finish that order and push the price against you.

Flow from other HFT / market makers is often very toxic. They are playing the exact the game as you.

Right, sure, and that game is not lifting the market, generally speaking.

Other market makers are often moving away from something they've seen but you haven't yet. When whatever that is hits you, the fills you got from the other market maker will look really bad.

Not aware of a market maker that also doesn't take liquidity as well. In fact, it probably would impossible to market make without also taking (you wouldn't be able to provide liquidity if your quotes were in cross with the market).

That said market makers do a lot more making than taking.

Usually too smart, on rare occasion they cheat. MMs inherently deal with information assymetry and adverse selection because they generally stand ready providing liquidity with quotes out in the world (though obviously width matters). Toxic counterparties are parties who decide to trade against you who have a better idea about “true” price than you. They might make or they might not, depends if the degree in which they’re right overcomes the spread they crossed. Other MMs can be (and often are) toxic.

or doing latency arbitrage

that falls into the category of knowing the “true” price better than you do

). By setting up a structure such that you profit during a crash (either by selling puts, leaning net short, or through some other method), you introduce an uncorrelated return stream that can really help

isn't selling puts directional? One strategy could be something like trying to find a way to bet on volatility but without a negative carry or at least as small as possible...this is hard to do. Taleb's universa fund tries to do this.

Sorry I meant to say buying puts (and have edited comment). Buying puts is directional and has negative carry. That's often fine because when your puts aren't making money your market making strategies should be doing well and vice versa

> it's hard to argue with success: Jane Street earned $6.3bn in the first half of 2020, up more than 10x from the year before ($, FT).

It’s actually quite easy to argue with that. It’s 1 (or 2 at best) data points. 6.3bn is meaningless without knowing the capital put to work to achieve that. And finally if your 10x YoY it’s just as likely you had a bad year before as a good one this year.

Apparently most of that came from arbitraging bond ETFs and bonds. The spreads started to diverge in early 2020 when covid was just coming out, and Jane Street had the balls (and cash) to hold until the spreads converged. Helped significantly by the US fed pumping a bunch of money into the market.

Regarding the last point in working at Jane Street versus research on fusion/cancer:

You could maximise more good by first working at Jane Street in your 20s, retire by 30, and then set up your own smal fusion/cancer research lab where you can do research without being tied to government funding and politics. By 30, many cancer researchers have barely finished their PhDs, so you won’t actually be that far behind scientifically, but you’ll be far ahead financially.

That sounds as if you can jump into a field without spending 10-20 years of learning and do cutting-edge research. I'm not sure whether someone who has done quant finance can make meaningful contributions to the actual science. So if your role ends up spending money and doing top-level management, why not just fund companies that do and stay in finance?

[edit] To add one prominent example - it's doable, as Jeff Hawkins demonstrated. Founded Palm, made money, then created his own brain research lab. As far as I understand, the neurological community has not embraced his ideas with open arms, but they are at least intrigued by his universal computational model of the brain. So that's a pretty big accomplishment.

I think Hawkin's work (including things done at Numenta, his company) is highly controversial in neuroscience. I have read some of the articles and claims and the biggest issues is that he produces a lot of vision papers, that contain no actionable models and thus ultimately are useless.

So either he's withholding whatever concrete insight he found, or he hasn't found it yet - I believe the latter is more likely.

whatever you may think about his work, he founded redwood and they do incredible work

> as if you can jump into a field without spending 10-20 years of learning and do cutting-edge research.

I know multiple people who have done this.

If you want a famous person, look at Paul Erdős. Always jumping into new areas of mathematics and solving problems at the cutting edge.

Or, to get to the current subject, Taleb using his background as a trader to jump to a career in academia, where many consider(ed) his research cutting edge.

I agree that a smart, ambitious person can become expert in more than one field in their life — but jumping to a new area of mathematics is on an entirely lower level than jumping from algorithmic finance to cutting edge biomedical, especially at the time Erdős was working.

There are a few people who did a complete switch to study rare diseases with no background.

Sonia Vallabh, and her husband, Eric Minikel are the strongest examples of these type of highly smart and ambitious people.

> Sonia Vallabh ... had just graduated from Harvard Law School.

> [Eric Minikel] ... had recently gotten a degree in urban planning from M.I.T

https://www.broadinstitute.org/bios/sonia-vallabh

https://www.broadinstitute.org/bios/eric-minikel

https://www.nytimes.com/2020/07/07/health/rare-diseases.html

>Taleb

He already had a PhD so it's not surprising he was able to enter Academia. But outside his books I'm not aware of anyone talking about his Research much.

I’ve never see his research brought up amongst quants or traders, but I like his writing.

Does anyone who works in this field know of it being currently applied?

I spent most of my career in finance including a hedge fund and several international banks.

Personally I really enjoy his books and recommend them to my friends and family. Professionally, I have never heard his name being mentioned.

You find the same 'fluffy' management books on trader desks (varies between firms).

- Some translation of "the art of war". - Tribal leadership and their whole "Tribe of tribes" nonsense - its name escapes me at the moment, but some leadership book written by a US marine? Because this maps directly to finance? - six sigma

Usually they are "management" focused chanting type material.

I'm not away of Erdos being at the cutting edge. There are far better examples of people moving between fields and doing very high-level stuff. For example, David Mumford, who has a great blog by the way.

Hawkins is a notorious con artist with nothing to show for almost two decades of work.

I can't judge that from an outside perspective, but to be fair, having nothing to show for two decades of work is an intrinsic occupational risk of science.

> I can't judge that from an outside perspective, but to be fair, having nothing to show for two decades of work is an intrinsic occupational risk of science.

How? In today's academic environment you won't survive even a few years without publishable research results.

Oh you can publish innumerable things whose content is nothing to show for, yet you publish something :)

Jeff Hawkins probably also had a several Hundred Million Dollar payout. That's in a totally different class than a Quant who cashes out at 30 with MAYBE $10M in the bank.

You’re overestimating the technical skills needed to do cancer research: there’s a reason why many wet labs allow high school students to come and help with research. It’s mostly grunt work and whatever technical skills can be learned by a high school student over a summer.

I would venture to say the average Jane street worker has done more good for society than the average cancer researcher or Alzheimer’s researcher.

For fusion research, the quantitative skills from many Jane Street people can easily transfer to make meaningful contributions to fusion research.

I do cancer research. You're right, the technical skills for basic wet lab stuff are not hard to learn. The hard part of cancer research is not learning how to pipette, it's learning how to ask and investigate worthwhile questions. Experimental design is subtle and requires wide ranging knowledge of sources of biological and technical confounders. Growing cells might be easy, but do you know how to debug a fluorescence microscopy experiment; in fact, do you even know how to recognize that it needs to be debugged? This is stuff you can learn over the course of a few years in a phd program, but it takes longer to become a true expert. Finally, what do you investigate? Cancer? What tissue type, which cell type, which proteins, DNA structures, or RNA structures are most important and least understood? Just absorbing a small fraction of the literature so that you don't ask stupid or boring questions is a lifelong task.

So you can do break-through research after having done a little bit of wet work in a cancer research institute, as a 30-year old who has been coding quant systems for a decade, and then become equivalent to a PhD in the field?

Or you can take your ~10M or whatever in earnings during a decade as an OCaml programmer at Jane Street and fund a cutting-edge cancer research lab?

Are you reading yourself after you type?

> I would venture to say the average Jane street worker has done more good for society than the average cancer researcher or Alzheimer’s researcher.

Might be one of the more arrogant things I've read. And I frequent WallStreetOasis.

Are you up to date with the current state of Alzheimer’s research ? Much of it has been shown to be fabricated ie average alzheimer researcher has probably made zero impact. https://www.science.org/content/article/potential-fabricatio...

Also I said the average researcher, meaning taken from the global population, ie not from a top institute. Jane Street is highly concentrated in talent that produce real results in the world.

The average cancer researcher has probably done more good than the average trading firm worker though.

It's wildly inaccurate to say that much of Alzheimer's research has been shown to be fabricated. The article you link to is about one person's work. Even though he is a very influential researcher, there must be at least thousands of people doing research on Alzheimer's disease, if not more.

I wonder if this is somewhat representative of what JS workers think, or not ?

What good has Jane Street done to a person living in Madagascar?

This is just blatant Jane Street (and more generally, hedge fund) propaganda.

Yes, you serve some role within the financial system, but you're not really relevant to society imminently and to non-western societies generally.

What good has cancer research done to a person living in Madagascar?

What has a baker living down my street done for a person living in Madagascar?

So you've established: People in Madagascar don't get cancer.

What good has your comment done to a person living in Madagascar?

Well, that person can now learn Ocaml because Jane Street uses Ocaml.

> It’s mostly grunt work and whatever technical skills can be learned by a high school student over a summer.

Who do you think is supervising the high school student? Where does the idea for the project come from? Where does the money supporting the high school intern' experiments come from?

But that's not the interesting part, right? That would be like saying that tech is simply assembling prototypes. The really interesting decisions are the strategic ones that require both a high-level overview of the opportunity landscape and some foundational knowledge of its feasibility. Or am I mistaken and it's simply brute force trials?

Yeah you’re right. My point is that the technical bar for entry is low, and can be attained maybe by spending one year in a top lab. You then skip the hazing ritual that is the PhD and postdoc and directly start your own small lab.

Spend your money attending conferences to make connections and get yourself updated in the field.

Hire technicians to help with your grunt work. Spend your days reading research papers, discussing science at conferences, and setting up new experiments.

The bar for doing some experiments, in an environment with tons of logistical, technical, and intellectual support, is indeed pretty low. A high school student could certainly learn to run a gel in a week or two; patching a neuron might take a few months.However, the physical "act" of collecting data, especially in the happy case where all of the conditions have been worked out and the results look "as expected", is a very small part of being a scientist.

More often, you are trying something that hasn't been done before and you're getting results that don't quite make sense. Here, experience and background knowledge seem key, and I'm not sure that you'll pick up much of that in a year, even in a "top lab" because experiments are slow. On top of that, you'll need to learn how to design experiments and analyze/present their results in ways that your peers find convincing, which is in itself a non-trivial skill. All this presumes that you're even able to find your way into a "top lab", but that's not a foregone conclusion either: these places can be incredibly selective even among people with a decade of experience in the same field.

Put another way, your answer assumes there's a lot of fat to trim in the PhD/postdoc stages. What is it and can it really be cut down by 90% as you propose?

Not to mention that tightening spreads, deepening books, and equalizing prices across regulatory/financial/geographical regimes is a pretty serious social good in its own right.

I understand that (as the article mentions) these folks clean up when the wheels have already come off anyways, but day-in-day-out, the spread on AAPL is one tick ($0.01) nowadays, rather than the 1/8ths that you'd get quoted by some loud guy from Jersey 30 years ago.

Citations on this stuff are hard to come by, but it does seem at least directionally true that these advanced actors are making less money over time even as the problem becomes harder. If that's true, it's money not going into the pocket of a middle-man somewhere. Multiply that by everyone's retirement account and we're talking real money.

If you're going to hold AAPL longer than a quarter, then the tick vs. 1/8 doesn't matter, and if you're not, your trade doesn't need to happen to support the core goal of financial markets which is to finance companies.

You're the best kind of correct, which is technically correct. But what I said is that "multiplied by every retirement account we're talking real money". Which is no-qualifiers correct.

That ETF that you should have your roll in? It's buying and selling securities all the time, and encountering friction along the way. And whether people have ETFs or individual equities in their (hopefully tax-advantaged) retirement account, across everyone with a retirement account it adds up.

I know that people often have a low-key axe to grind about advanced market actors being "bad", and I know that politicians go to the well with this narrative all the time, but it's misleading at best and usually just demonstrably wrong. And with nothing but respect, I tend to bow out of conversations where people push the issue past a comment or two.

There are exceptions: Citadel paying 2x for PFOF on Robinhood vs. Schwab to get optionality on internalizing against dumb flow? Yeah, that's pretty iffy. But in general advanced actors are slicing strips of meat off of each other to the benefit of 401ks everywhere.

> That ETF that you should have your roll in? It's buying and selling securities all the time, and encountering friction along the way

I really hope it isn’t, or it would be making lots of tax events! I hope it’s doing in-kind transactions like all the normal ETFs.

> Citadel paying 2x for PFOF on Robinhood vs. Schwab to get optionality on internalizing against dumb flow? Yeah, that's pretty iffy. But in general advanced actors are slicing strips of meat off of each other to the benefit of 401ks everywhere.

No, robinhood average order is just smaller so less risk of adverse selection.

I didn't think that a digression about the tax optimization opportunities of in-kind securities swaps would be enlightening to a general audience.

As for your second point, I guess neither of us works at Citadel so we're both guessing, but if you agree that there is a market for order flow and that the most charitable interpretation of why that would be the case is because of the attached optionality for internal netting, then you're sort of making the assertion that all PFOF is equally valuable, which would be a hell of a coincidence.

As a sort of side note, I regard the cherry-pick the parent with ">" prefixes and go after snippets of what they posted as basically the lowest form of discourse on HN in spite of how popular it is, and I would encourage anyone to try to reply to someone's entire comment rather than just trying to find the weld points and lean on those spots. It's pretty weak.

> But in general advanced actors are slicing strips of meat off of each other to the benefit of 401ks everywhere.

I am not sure I understand. That would mean that the number of advanced actors would stay stable or go down over time (generally much research shows that markets tend to concentrate even in pure random trading, so the number of advanced actors should go down). Is that actually the case?

As I've mentioned elsewhere in the thread, it's notoriously difficult to get citations on this stuff so take with a grain of salt, but I've heard that in 2019 the "HFT" industry (defined some way) had cumulative annual profits in the US of somewhere between 2-4 billion dollars. That's a long holiday weekend for Google or FB. I've also heard that this (inflation-adjusted etc. etc.) this is down sharply from ten years before, when spreads were wide and undocumented order types were winked at.

To wildly oversimplify, market makers will tend to drive the spread down to the tick size, and arbitrageurs will tend to put themselves out of a job.

For the industry as a whole to be growing either in distinct actors or cumulative top-line, the number of markets and instruments and general financial activity has to be growing faster than the big dogs are eating each other. This is my (semi-informed) guess.

Is Citadel paying 2X for PFOF on Robinhood vs Schwab because it is dumb retail flow or due to increased optionality because it is inherently built in slow transmission flow to reach the execution platform?

You are really going to need a citation to back up that the core goal of financial markets is to finance companies.

That is, in my view, at best an ancillary goal (notice that most money in the markets doesn’t participate in buying shares from the company itself).

That may be what you want the markets to be about but every other participant has other desires from the markets and the great thing is they can all get what they want from them.

Markets in equities exist because companies want finance enough to be willing to sell the equity. Not sure why something that elementary needs a citation.

It's also true there are many other participants with many other strategies to extract that value created by the companies from acquiring and merging them to collecting dividends from a balanced portfolio to day trading, but the reason the market exists in the first place is because companies that create value need their capital in order to do it. As you correctly point out, most of the actual trades are secondary market ones involving companies not in the process of fundraising, but those trades are still positive sum inasmuch as without liquid secondary markets, companies that create the actual value might have found it too hard to raise funding. The difference between being able to sell TWTR on IPO day or shortly afterwards and being forced to hold it until an Elon Musk comes along and follows through with its existence has a huge impact on its ability to raise funds and grow. On the other hand reducing the time between trades down to smaller sub-second microsecond intervals is - whilst useful to people trying to win at essentially zero-sum trading games and inflating asset prices very slightly - going to have a pretty minimal impact on whether companies create more value by raising more funds.

I’m not sure you’re reading that correctly, since the response concerned the idea that the core goal of financial markets is X, and you respond with a statement on equities markets, which by definition only concern financing companies.

Equities markets are a piece of the pie. The largest, by far, for the kind of HFT we’re talking about, but a fraction of financial activity.

The core goal of financial markets is to gather and match prospective buyers and sellers so that trading can occur.

If the only people who trade AAPL plan on holding it for 10 years then by the time they want to sell it there will be no one to buy it from them, since the probability that someone else will want to make their once-every-10-years trade at the exact same time is zero. In order for long term investors to function they need liquidity to enter and exit positions.

But it doesn't have to happen at the exact same time? Limit orders exist, no?

Further: Suppose you had an auction on shares once an hour, or even once a day, but no continuous trading. Would that make the world any worse off? (except for high frequency shops?)

That’s a moralistic positivistic take on a real friction problem which has been reduced. It doesn’t matter what people use the market for.

But what if you hold a mutual fund that bulls and sells AAPL regularly as part of managing inflows and outflows?

I would suspect that almost zero people do this because working in an environment changes who you are as a person. If you spend a lot of time around cancer researchers you will think that cancer research is the most important thing in the world. You would need almost monastic mental compartmentalization to work at Jane Street for N years and remain singlemindedly focused on cancer research.

I thought about that often. Why are highly intelligent, passionate young activists not working into the industries they despise to change the system from within. But you're right that the system you're in changes you, corrupts you. You'd have to sacrifice a lot to climb the corporate ladder, doing things you despise, just for the chance to blow things up years, decades later. Your idealists friends would distance themselves from you. You'd have to constantly remind yourself that you're doing wrong things but that it's ok, because it is part of a bigger plan. It would be very isolating. You'd probably sacrifice your sanity for a foolish plan.

Most people think that their values come from some immanent "Self" but in reality our values mostly come from our surroundings. The same baby with the same genetics raised in Broken Arrow, Oklahoma vs. Upper West Side New York will have extremely different values, go farther than that and the difference in values is almost unrecognizable. If you or I grew up in wealthy families in ancient Greece, we would think NOT owning slaves was weird and suspicious.

Tangentially related is the movement of Effective Altruism, which is basically espousing taking a high paying job and then using the rewards to make a change.

The existence of a "movement" makes it much more likely to succeed. If you are working at Goldman Sachs during the day, you need to be talking to Effective Altruism friends at night, or you will almost certainly be washed away in the current of Goldman Sachs value systems.

I'd temper the above statement a bit. The "get rich, then donate a lot" strategy is one of the paths popular in Effective Altruism.

“He who fights with monsters should be careful lest he thereby become a monster.”

“Battle not with monsters, lest ye become a monster, and if you gaze into the abyss, the abyss gazes also into you.” Nietzsche

Don't cut out the best part of the quote :-)

Or suffer a loss to cancer. That changes kinds quickly too

By now, finance and FAANG have minted a very large number of tech millionaires. So, in practice, you have you ask yourself why ~nobody has actually done what you say. Personally I don't think it's because of a lack of funds.

Bill Gates?

We were talking about retiring at 30 to do science, not retiring at 50 to fund science

>By 30, many cancer researchers have barely finished their PhDs, so you won’t actually be that far behind scientifically, but you’ll be far ahead financially.

A lot of people trying to change their careers would like to have a talk with you about this, I bet.

Ph.D in CS is 5-10 years ahead of newbie trying to learn computers

The article should not have delved into this as its a can of worms - stick with the industry, programming and math.

Its funny that the article uses a “chess champion” and a “concert pianist” as examples to to argue that you don’t question their occupations when it comes to being a benefit to mankind or not. I mean, the huge fucking salaries, where does the money come from? from fucking trees?

WTF! Seriously? I predict this will be one of the first article/HN post that has negative publicity for Jane Street .

For some reason articles on hedge funds bragging about intellectual abilities if their employees always seem to invoke these professions (chess champion, concert pianist).

I'm still waiting to see them bragging about having top proctologists in their team ;)

> I'm still waiting to see them bragging about having top proctologists in their team ;)

They tend to be on the regulatory side.

I think you are wildly underestimating the cost of running a world class lab.

Even if you retire with 10M by 30 you aren't going to run a world class research center with that kind of money for very long, or at all. Hell Land, buildings and equipment probably eat most of that right out of the gate. MIT's Plasma Science and Fusion Center had to shut down when their funding dropped from $28 to $14M per year. So at 10M you could Fund, forget about building, a center 1/3 the size of MIT's for 1 year.

Very easy to plan in theory.In reality, if you've been at a place like Jane Street for 10 years you mostly likely will only leave if you are retiring.

I know we're supposed to assume the best interpretation, but I'm struggling to imagine how can someone think this is a reasonable comment other than through self-deception.

Broken window fallacy.

Nice try to justify your bullshit job, though.

"Make a ton of money and donate it all" is an impactful way to maximize good.

It's also something that people almost never seem to execute, usually it ends with "make money and donate a small amount of it".

Signals and Threads[0] is a podcast featuring interesting conversations from engineers at Jane Street

[0] https://signalsandthreads.com/

Very interesting podcast - crazy stuff relating to the very edge of possibility in low latency computing.

Thank you for the suggestion. Looks like it's doesn't get published often though

Yaron Minksy is probably too busy.

But the tech blog is really good too.

https://blog.janestreet.com/

There's one thing that always baffles me about this kind of market work. Let's for the sake of argument assume that HFT and other sophisticated market making activities are crucial for price discovery and other great social benefits. Then why does this amazingly important social good get mostly turned off over 80% of the time[1]? Even as a retail buy-and-hold investor in boring ETFs not being able to trade outside normal office hours is an inconvenience. Surely the world economy has even more uses for trading at all hours than me?

[1] https://www.nyse.com/markets/hours-calendars

Without arguing in favor or against the usefulness of HFT, the reason trading hours are limited is to increase liquidity during the specific hours that trading takes place. Liquidity is important for various reasons, in particular it helps reduce spread and thus there are better prices. Trading during other hours is possible, either during pre-market or after-hours, and there are even exchanges that enable trading on weekends, for example https://www.ls-tc.de/de/faq . During weekend trading, the spread is significantly higher.

The majority of the market, by flow, is open 23H a day during the week, and opens Sunday evening.

I will say up front that I don't think the social good is worth what we are collectively paying for it, but I do think the market hours are a reasonable device. This is basically because there are humans involved and they need to sleep (Matt Levine has written about this).

If you want the best price, you need to have all of the market participants bidding together. Market hours serve as a coordinated period in which ~all market participants agree to be online and bidding. Prices, thus, get stale overnight. But we assume that that is mostly okay, as business is normally conducted during business hours, and we assume that transactions can wait until the next day. ACH transfers take multiple days! (technically so do stocks, but that's mostly invisible to retail traders).

If you're a retail trader, I would caution you somewhat against trading after-hours; there is very little liquidity and it could cost you 100s of bps more.

Legacy reasons.

You can trade outside of market hours just fine and many products (e.g. E-mini S&P 500) trade all night. It's just that a lot of companies publish news right after the market closes so prices are more volatile. And people sleep or play videogames at night so there's less liquidity.

This and getting people to click more ads. What a great use of innovation and bright minds.

It's trickle-down programming. They're inventing the next big database technology or whatever by doing busy work and that will eventually enable somebody else to produce something of actual value to mankind.

Most of the hard problems in the world aren't technical and the ones that are have lots of people working on them.

I agree, genuinely depressing to think of what is lost from talent being allocated this way.

The first argument made in favor OCaml is very similar to Paul Graham's Beating the average (http://www.paulgraham.com/avg.html), if anyone wants to read more about that kind of reasoning.

Most of this article is pretty interesting and unusually insightful about quant firms. But I find this sentence to be utterly disgusting.

> Trading is a lottery operated by market makers, and like the lottery its social function is to convert mass innumeracy into funding for better causes.

It’s basically saying “we should have your money because we know better than you”. Maybe true, but I find it a very weak argument for the social function of a quant firm. Especially when lotteries are essentially a form of regressive taxation.

Isn't this what taxes are?

Also just ignore that line, it's not actually true.

Curious how people are so interested in Jane Street, ostensibly because they do technically challenging work, but much less so about other places where the work is at least just as challenging, but the money sucks.

You're curious about how people would choose between two equally interesting jobs where one pays a lot more? I'm curious about how anyone could be curious about that.

I mean stuff is either interesting for someone or it's not. Money is not relevant to being interested by something.

I think people want to convince themselves that they're interested in high paying jobs such as those at Jane Street because that would make their lifes much easier (they could go work there and make lots of money). Similarly, some women try to convince themselves that they love this well-off, solid guy who's courting them - marrying such guy would make their lives much easier and nicer.

Money does make some things easier. People make job choices based on:

- lifestyle - how much does this job affect my work/life balance? Do I have to travel far / work late?

- challenge - how hard is it? Will I enjoy the work?

- impact - what's the mission of the company? What am I contributing to?

- salary - how does the job fit with my financial goals?

- prestige - can I talk about / be celebrated for what I do?

Possibly other factors as well. But if everything is equal, but one job pays more than another (and if it's Jane Street, one year's work might be 3 years' work somewhere else) then it makes sense to take it.

I went through a relatively brief conspicuous consumption phase in my youth, but most of the people around me actually didn’t.

What money bought them, and why I now want more than I have, is the ability to delegate both tasks, but even more importantly worry, to others. If I have a brand-new car with a warranty, I spend zero worry that it’s going to break down. If I have a hot shit CPA and/or lawyers and stuff, I spend zero worry than I’m going to dick up my taxes or something. If I have a rhodium-plated health plan, I don’t worry (much) about getting sick. Ditto fitness trainer, ditto housekeeping service, ditto laundry service.

What this really buys a passionate hacker (really a passionate anything) is time unencumbered by stress, which is very different to just time. I can really focus on whatever I want to.

Usually this means I have to work hard and stress about technical stuff, but I far prefer, borderline like, being wrapped around the axle on technical stuff. I hate worrying about that other stuff.

How anyone could fail to consider this a reasonable tradeoff is beyond me.

There's nothing wrong with pursuing money.

You answered your own question...

Prestige matters to young people, because it helps them date and find social networks.

> the winners get a job from which people routinely retire rich in their 30s

I'd love to know where this claim comes from! I'm not sure how much/what supporting evidence there is. It doesn't fit _my_ experience of people in Quant Finance. Of course, what does "routinely" mean here? 20%? More?

Why do all these companies with pretentious attitudes exist when the average* software still takes 30 seconds to show a paragraph of text? Ironically whenever these companies take the security test, they not only fall flat on their face, but are proven to not have the slightest clue how to do basic stuff like string escaping. I actually looked at the code for one of the top Haskell companies with the same attitude, and the story I just wrote is precisely what happened. Jane street sounds like a level 2 company like these Haskell companies and Cloudflare: They can escape strings, but only in places that have been famously exploited thousands of times, like SQL; they don't know how to actually know when the problem presents itself in a different unusual context, which they may have made themselves. It seems you need a million dollar employee income to reach level 3, and for level 4+ you simply need to be someone who is genuinely interested in the topic (as there is no monetary incentive) and have spent 10 years reaching it. Also, this applies to all aspects of tech, not just software security.

* not even average, this describes almost all software made in the last 20 years.

What does string escaping have to do with market making?

-- only managed to make it half way through the article so apologies if this was covered later - re: the intern game - if the game is confidence in the probability of your answers - couldn't you deliberately get the answers wrong and just bet low confidence in your answers? - this seems like a really stupid comment on my part so I presume I'm missing something important --

You only get more tokens when you're right. So to "win" you have to bet high when you know you'll be right, so you get the most tokens, and bet low when you're not sure so you don't lose too many. Getting it wrong only loses you tokens.

No context around Jane Street, but I'd expect the goal to still be maximising your return / value. The people who are better at assessing probability and risk will have a higher value in aggregate.

Filter out those who made bets too big to avoid outliers.

Presumably the goal is to have a lot of chips at the end (more than you started with?). I would assume if you bet 10 chips, you get 10 for being right, and zero for not. So betting 0 chips all the time probably won't get you the job!

This is wrong.

The 100 poker-chips interview thing = interview BEFORE internship.

As you would expect, a job offer is based on full internship performance.

I don't have personal experience but I have friends who interviewed there.

For all the mysticism surrounding them, what they do is very simple. They just do it well.

From the article:

> One example of this is NAV trading (Jane Street has a paper here), where an investor wants to place a large trade in an ETF and agrees to buy it at some future point at whatever its net asset value is, less some small fee.

Should this say "agrees to buy it at some future point at whatever its net asset value is *NOW*"? Otherwise, I'm confused, why wouldn't the investor just buy it later?

Edit: if you remove the second 'at' it makes sense.

I think they mean that the buyer will agree to pay $5000 now for say 10 shares (close to current valuation), and get it in a week regardless if they will be worth $0, $5000 or $100000 at that point. They would prefer to buy it now, but can't, and thus are willing to pay a fee to make it happen.

However, the motivation (and pricing) is different from futures trading: here the buyer would prefer to buy the asset immediately, but because of market inefficiencies or unavailability it's not possible. So some dealer figures he can make that happen in a week, takes a small fee, and agrees to the trade. In the meantime, the dealer might want to buy something that correlates with the value of the actual asset to cover his bet -- e.g. they might be able to buy most of the stocks in the ETF in roughly the same amounts, and just accept the remaining risk.

There is however a chance that they will not be able to complete the transaction.

No, the original statement is correct. Page 3 of the linked paper has a diagram.

https://www.janestreet.com/wp-content/themes/janestreet/pdf/...

What tax do these type of companies pay?

I'm gonna guess they aren't paying the "retail" short term capital gain tax.

Yes, they pay short term capital gains taxed as ordinary income for equities. For futures they pay a blended 60/40 long-term/short-term rate, since all the futures trading is taxed that way (including for retail)

Pretty much, except for Susquehanna. See https://www.propublica.org/article/jeff-yass-susquehanna-tik... for details.

Assuming it is accurate, the final sentence in this article is especially notable.

They'll have their cost centers in places like NY and London incorporated separately, making consistent losses, and then the arm doing actual trading will be in Bermuda or somewhere with 0% business tax.

Under this structure, how are trading profits shifted to the cost centres to pay for operating expenses?

Licensing IP would probably do it. Oh, the other direction - just make some returns in the place with operating costs.

These kinds of firms are one big reason we need a sales tax on stock trades. Stable, long-term investments are much better for the economy.

Why should that be less?

Something I don’t understand:

Why haven’t their gains been arbitraged away? Conceptually what they do seems simple enough; and presumably you just need capital to do it. Hell, their own former employees could theoretically compete against them - as could many traders who would pay to learn those strategies.

So why are they still making so much? I don’t understand why their “advantage” hasn’t been arbitrated away into a commodity business.

I worked in High Frequency Trading over a decade ago (not Jane Street) so I have some insight into this. In general, markets are always evolving. I've seen a team of four traders that make $500k/day go down to $0/day over the course of 6 months.

So you're actually right more than you think. Plenty of teams that make money do stop making money over time (or make less). I'm sure there were teams at Jane Street over the years that have folded or dissolved because they stopped making money. But as a firm, they may be making more money.

In the HFT firm I used to work for, that one team went from making $500k/day to $0/day. But another team went from making $30k/day to $2M/day. That's right, a team of 12 people making $2M/day. They probably ate most of the former team's lunch. That's how it goes, survival of the smartest and fastest.

So why hasn't Jane Street's edge been arbitraged away? Some of it has, probably by people within Jane Street who found even more edge. When you have hundreds of the brightest minds in the world, who's going to eat your lunch but yourself (and a few other high quality trading firms)?

But ultimately your assumption is wrong. What they do is not simple at all. It is not like building a simple CRUD application. Throwing money at the problem does not mean you will succeed. You will most likely fail. Strategies that used to work may no longer work when markets change, and markets are always changing. So some traders may try to take their ideas and apply them elsewhere, and they may have some limited success (not to mention the high quality speed and infrastructure you need to win), but when the market changes in 6 months, are you smart enough to keep up?

> They probably ate most of the former team's lunch.

Are you able to elaborate on this?

I’m assuming that teams wouldn’t be sharing strategies with other teams. Is that accurate?

Would these other teams be independently finding some strategy that is either directly better than another internal team or is having some indirect impacts on other teams?

> Hell, their own former employees could theoretically compete against them

That happens, with mixed levels of success. But these firms are more than just IP. Their moat is:

- Lower fees, negotiated based on their volume and relationships. Crucial given margins of 0.02%.

- A well-oiled machine that makes the machine. This includes culture, branding into recruitment pipeline, and so on.

- IP has a short half-life. The machine that makes the machine is more important.

- Scale advantages -- code sharing between teams and asset classes, which is hard to replicate in a small group.

- You need to have perfect execution on every vertical to have a good shot. Devs, researchers, operators, relationships.

It's also common for that IP to not all be known by a single person. Division of labor can be used to protect IP.

Imagine someone outside of the tech community thinking along this line...

"Making high performance CPUs that are also highly power efficient should make a ton of money. Why isn't everyone doing it?"

Well, turns out that isn't exactly something that a small group of engineers can whip up in a garage anymore. Same goes for highly efficient market making systems.

CPUs operate due to quantified phenomenon. They're well understood. They've been refined over nearly 100 years.

HFTs came into their own over the past decade or so -- during a time of falling interest rates, unprecedented growth, and notable lack of regulation in financial markets.

One of these things is not like the other. I'd be entirely unsurprised to see most HFTs turn out like Lehman Brothers, Enron, or AIG. They all lasted more than a decade or so. But their gains were fraudulent and they failed spectacularly.

Devil in the details. MMing is conceptually simplistic but the operational costs are huge and are generally getting worse. Making while fighting these costs against competition playing the same game as you turns non trivial real quick.

That said MMs have mostly consolidated heavily over the last decade (due to many firms collapsing against competitors) so in some ways the business has been commoditized. Not sure if true of MMing ETFs as an authorized participant (JS bread and butter) though, idk much about the logistics there.

It's not just like you can just have a few hundred lines of secret sauce implemented in Python and then go and fill your boots.

The costs of maintaining a trading platform are very high. You have to be colocated with brokers/exchanges, and have a full market data and trading platform optimized down to microseconds. You need a large data and processing farm to backtest your algos. You need the legal structure to dodge all the tax. You need access to lots of GPUs and FPGAs to train your models and execute fast.

At least on the quant side, I think the typical sentiment is that most researchers aren't interested in ops / developing infrastructure / curating datasets.

How does that answers their question?

Like other investment options ... we tend to look at the successful few and assume that they know something special, or have something special. But over time, a few are just lucky and most are not, and we have no way of predicting luck :)

Because they are the ones arbitraging the gains away. That's why there's no opportunity left for you average punter to just start his own little script that take orders from one market and put them on another.

All the players that are left are highly sophisticated technologically, but also in terms of ecological position. For instance you have Citadel doing PFOF with Robinhood. Once you lock in a deal like that, you have a special position in the market. Having access to lower fees is also an important part of the game, and it only happens for players who are already in the game.

If lone wolf day traders can make good money why can't they?

Lone wolf traders are satisfied in income in hundreds of thousands of dollars per year, while a large company wants millions or billions. There are way, way more opportunities on the market to make just a couple hundred k than to make a billion. In other words, a lot of the opportunities do not scale well.

Over any sensible period of time, like a year, essentially all lone wolf day traders lose money

Then the article would have been about whoever beat them.

I first heard about Jane Street taking the first computational linguistics course that used OCaml. I followed them over the next decade, every couple years seeing them pop up.

The given reasons for using Ocaml outlined in this article is interesting. It makes reasoning about complex systems easier. And making an "esoteric choice" earlier has advantages in hiring.

Assuming you give back to keep it going.

I don't have the advantage of secrecy where I'm at. But I'd be willing to guess that strategy could apply to other languages and markets.

Have fun first movers.

Nice article. It would be great to see a similar one about DeepMind

Quite a few inaccuracies in there. The ones that jump at me:

  - OCaml does type inference, so you don't actually declare the types and have the compiler check them, as stated in the article.
  - Investors are not market-makers, the two words actually refer to the two types of opposed participants in the market.
  - OCaml is the language used for research, but they actually have a lot of developers working on the compiler and on libraries for OCaml which are themselves implemented in C or C++.
  - Jane Street is hiring massively and not nearly as exclusive as advertised here, though they do indeed pay slightly above the average. Most likely they had a few good years and are investing the cash they made into hiring expensive staff.

Downvoted because I feel this is nitpicking for nitpicking's sake, and it gets more things wrong than right.

> OCaml does type inference

This is an uncharitable interpretation of the author's intent.

> Investors are not market-makers This is a very uncharitable interpretation of the source:

"In one sense, every investor is a market maker and the only difference is their timeline. Jane Street is far along the continuum towards strict market-making: being willing to buy and sell assets at a price close to, but not exactly at, the market price."

> they actually have a lot of developers working on the compiler and on libraries for OCaml [..] in C or C++

Yes, and? The author still makes the correct point that they gambled hard on OCaml.

> Jane Street is hiring massively and not nearly as exclusive as advertised here

I bet they're hiring very selectively for the high value core jobs discussed, even if they have a large support staff that does things like writing OCaml infrastructure in C/C++ and gets paid much closer to non-hedge-fund rates.

Yes, it uses ML-style type inference, but that doesn't mean you are literally unable to annotate types, and the compiler is absolutely still doing type checking. I'm sure people like Jane Street annotate everything.

In addition, perhaps a small point relative to the first, but in Ocaml, the arithmetic operators perform no type inference; there's a separate operator for float-addition versus int-addition, and so on. This somewhat limits your exposure to potential automatic type conversions.

That is not the idiomatic way to use OCaml, so I wouldn't assume they do that.

At least in similar languages like Haskell, what you do is let the compiler infer types and then press an IDE key combination to write out those inferred types as part of your code so you would get an error if you ever accidentally change the types.

Writing `mli` files is pretty much idiomatic or at the very least, not unusual.

Some counter-points:

In Ocaml-world it is customary to write .mli files that specify the types of exported functions and modules. Those are then checked by the compiler against the .ml file with the implementation. In the .ml file you indeed use type inference over annotations almost all of the time.

The Ocaml compiler is largely written in Ocaml. C and C++ are not used very much at Jane Street as far as I know.

This reads like a very rosy picture of what these firms actually do. Surely they are secretive and tight lipped about all the money being made in low risk trades.

There are known loopholes that market makers get to exploit since they help keep the casino going. No need to make its a noble profession or compare to impact to actual economy or mankind.

These are the worst of the worst when its comes to exploitative and manipulative behavior to make money over retail trades just as a Hedge fund selling CDO's to pension funds.

> There are known loopholes that market makers get to exploit since they help keep the casino going.

Like what? I work at an HFT and I'd love to deliver a new strategy to my manager.

> to make money over retail trades

You can call them vampire squid from hell but they don't exactly take money from retail, they tighten spreads for them if anything.

Wouldn't electronic front running take money from regular folks? Perhaps not from retail trades, but from mutual/index funds, pension funds, etc.

Front running is illegal. However, making a better price prediction than the rest of the market and trading on it is not the same thing as front running.

[1] https://www.investopedia.com/terms/f/frontrunning.asp#:~:tex....

Market makers and retail traders have aligned incentives. Stop scaremongering.

My greatest regret is not getting into this firm

There are a bunch of these firms. And when you pass the gauntlet, you realize that the people are smart but no smarter than at other firms. At some point, the strict hiring filter just produces noise.

If anything, having that many achievers results in bored people doing things that are suboptimal for the performance of the firm as a whole. Whole divisions of wasted talent spawn and self perpetuate.

It's the hiring process hazing ritual that sets the allure, there's not much else to it.

Don’t mean to hijack this thread but seeing as you have a background in the industry I was hoping you could answer a couple questions I had:

1. What do these firms typically look for in support staff? I’m asking about non trading/quant roles like recruiting/ops/facilities management?

2. What’s the potential upside, not specifically financial, but more along career growth and opportunities for different roles within the firm if you join in a support function?

Appreciate any insight you may have.

I've spent time at a very large and well known hedge fund and I also have family at JS.

Regardless of what the individual you responded to thinks.. Firms like this have very difficult interview processes. They are looking for something "Special" and this excludes the vast majority of applications.

I took a taxi to my interview, and the taxi driver himself told me he drives many people to the location for interviews, and drives a lot of unhappy people back (failed the interview).

It should tell you something when even a local taxi driver knows how difficult it is to get into these places.

I will try to answer your questions as well:

1) I did support work when i was at "hedge fund" - They want people who can think outside the box and be a culture fit. their culture is well known, and you either fit in or you don't. There is no "faking it".

They generally hire fresh grades from ivy league schools. This way they can indoctrinate the culture. This is not always the case, but probably 70% of their employees were done this way.

2) Many of my former coworkers are now CEO's, COO's etc. Besides the money the culture encourages you to push past your limits and grow. One guy was a developer, he's now the CIO for an international makeup company..

At the firm I worked at, it did not matter what your role was. If you wanted to change groups, you would be given a fair chance to take the tests. if you passed, you were in the new role. The tests were INTENSE... but many "techs" moved to business roles over the years.

You might have a focus-in ability to grind on details - that will play.

There are many support roles, one is research, and that can mean sorting through a daily pile of a few thousand "documents" (ranging from a single paragraph to a thousand pages) and sorting them into groups, and then being able to rapidly summerise the salient features.

This bleeds into training AI to do the same .. while remaining aware of the nature of the material to be a human check on the AI.

There are also roles for people that can map or otherwise visualise data, pander to the needs of the core earners so that they never need reach far for what food, drink, personal life support they need, etc.

If you're aiming for support you likely want to present your discretion and ability to seamlessly play well with others as dynamics and demands change.

Often a background or a degree from a prestigious university in the arts. Bringing culture and energy to the office that focuses on people and humanity instead of competitive math type geeks. Some firms like to feel like patrons of the arts giving writers actors poets etc a better job than waiting tables while exposing the firm to there influences.

I wouldn't say most of these roles are anything different than you'd expect at most tech companies unless you are involved in the production trading/tech activity (trading-related ops, recruiting for traders/devs). Helpdesk/facilities usually isn't anything special.

There's also the boat loads of money.

I'd be retired by now.

I don't know why you think that. Not everyone who makes in to these places comes out wildly rich. I know a smart guy from college who spent years as a team lead at a top HFT firm and wound up making less than most junior-level software engineers. You make what you kill, and not everyone is killing a lot.

Fifteen years ago I had a job offer from Jane St sitting in my inbox, and I turned it down to work in tech.

Could I have made more money at Jane St? No idea. Probably? But money isn't exactly holding me back right now.

Would I have felt like I was working on interesting problems? For me, personally, I don't think so. I don't find abstract problems as interesting as I do practical ones, and, practically, working at Jane St is working to make a few rich guys incrementally richer. Not really a problem I'm interested in, I guess.

(As an aside, it seems to me retention is much higher in tech than it is on Wall St. The rosy view of this seems to be that Wall St pays so well that everyone retires early, but then again, there's a reason they call it "compensation.")

You have to make your own choices. Jane St has a gleaming reputation--and maybe, for you, it would have been a perfect match!--but not getting hired there seems to me to be a strange thing to consider a "greatest regret."

In my experience, retention in quant finance is much higher than in tech (barring a few firms)

People don't leave.

a high wage is a kind of golden handcuff

I don't feel it's primarily about the money (but it helps). If it was about the money, it'd be the uncertainty of the bonus, rather than the wage itself.

I interviewed at Jane Street a long time ago. Halfway thru they gave me an office tour. All employees were packed together on one side of the floor, screens everywhere, no personal space at all. I couldn’t see myself sitting there for 10 hrs/day. I limped thru the rest of the interview. Other firms and banks pay well too. The work is always boring though.

companies are big on culture fit because of wanting people happy with being forced to spend their waking hours in those conditions inflexibly

So you didn't get as rich as you could have and might not get to retire at 30, go live your life. A friend of mine and I both applied for a HFT firm out of university, he got in and I didn't, but based on how he described it over about 18 months working there, my greatest regret would have been taking that job, it sounded like a dismal place to work (with platinum handcuffs).

Perhaps it would be worth it because he can retire 20 years earlier than you?

> The other mitigation strategy is: just buy some puts.

I wonder who are the counterparties selling puts to Jane Street. My cynical view is that they are losing overall but the traders don't care because they are winning in short term (when nothing happens) and may have already changed their job when the market crashes.

They don’t really have to be losing in the long term, being short deep out-of-the-money puts nets you an option premium if the underlying never crashes, and once you delta-hedge that position, you can remove the tail risk from your portfolio

Yes it's not necessary for them to be losing in the long term for Jane Street to be profitable, but I suspect they are.

thoughty52@gmail.com

1. It's realllyyyy hard to get hired. So many stories are along the lines of "I applied...blah blah... didn't get in"

2. You have to solve over the phone very hard math questions to make it past the initial screening stage. I dunno what comes after that.

The highest-stakes gambling events in the world are typically very discreet, invite-only affairs. One that might be close to the top in terms of available winnings happens at the end of Jane Street internships: interns get a stack of 100 poker chips and spend half a day getting asked brainteasers and then betting on their confidence in the answers. Some of these questions might be pure math and probability questions, some might be more abstract bets on making a market in some outcome, and apparently one of the questions is a tough probability question where part of the prompt is to bet on how long it will take to get the answer.1

I dunno why brain teasers are so important. I increased my account by 5x since the lows of covid to present with simple large cap tech and etf strategies (tesla ,tqqq, tecl, amazon, and others ). I don't need to mentally visualize 3d shapes intersecting 2-d planes or count colored vertices of hypercubes to make money or develop good strategies. Just some basic calculations and some other analysis..maybe advanced high school level. It's like if you want to find good traders, look for people with good track records.

If I were going to start a fund, I would do away with the puzzles. Instead what I would do is look for people who seem to have good track records on reddit or elsewhere and some decent risk management, like on wallstreetbets. There are thousands of users there and then I would try to find the best ones and try to quiz them on risk management to see if they are relying on luck or have a system. Recruiting from reddit or twitter is harder than linkedin, but I think the quality is better because you are seeing actual traders in their element. instead of hoping that puzzle skill will lead to trading skill, you just pick people who are already good.

Continued:

The other mitigation strategy is: just buy some puts. Markets usually don't crash upwards, but they do have a habit of crashing downwards. And for a market-maker, a crash is a uniquely interesting situation: volume is high, spreads rocket up because people are afraid to trade or don't have the liquidity, so an active participant can make a staggering amount of money. (I liked this Reddit AMA: "Yeah, 08-09 was insane. I've heard stories. No one knew what the fuck was going on and everyone was on edge. Then it all turned out fine and everyone got PAID.")

Puts bleed out a lot. Even during bear markets they lose money if the path dependency is unfavorable. The covid crash would have been perfect, but the 2022 bear market has been much more gradual, so puts would have done more poorly.

Yes, the 'crashing down' aspect is captured by the skew or smile. That's why a 20% ITM put will have a much higher IV than a 20% OTM call or be much higher than predicted by the volatility of the underlying. In some cases it will be massive...like a 38% IV compared to 11% for the underlying. So many people have tried to make put strategies work, and I have yet to see anyone do it, but if someone actually could I imagine they would not tell.

So you are doubling your money each year? Do you have a forward strategy to keep that up?

Looking for people with good track records is a terrible way to choose traders. See: https://m.youtube.com/watch?v=zv-3EfC17Rc

Tldw: meets a person, picks 5 horse winners, gets then to invest. How did he pick 5 winners? Emails 1000s of people, using a permutation per person. The person who sees the 5 wins thinks he has a system.

Real life version: 1000000 monkeys given ability to trade. Scratch bum=buy, scratch head=sell. One of the monkeys will certainly have a good trading record by the end of it.

It depends if you are getting new money or not. For a lump sum investment, depending on market cycles it's possible to structure the trade to optimize returns. If you assume that bear markets are every 6 years , there are certain simple integrals for computing this in which you input a certain starting capital and then a certain risk -free rate and then the capital is split between two assets like cash and stocks. When the bear market is triggered, you switch from cash to stock. [0]

But all you need is a bull market to 50-100x your money with 3x funds https://i.imgur.com/PF7XEaR.jpg

If 7/10 past decades are a bull market then odds are you will make good money.

Market neutral strategies are different though.

[0]

https://www.wolframalpha.com/input/?i=3000*%28%28integrate+1....

A calculation i ran to answer this problem shows that if you have $10k and split $3k of into cash that yields 3%/year and the $7k is put into TQQQ, which generates a long-term CAGR of 53%/year, approximates the actual returns of TQQQ .

So this turns the $10k into $1.5 million over 12 years, which is close to the actual result (100% or $10k invested in TQQQ at the start), assuming a crash happens every 8 years (modeled by exponential distribution and based on empirical evidence going back the past 100 years) and and then after TQQQ falls about 70% the $3k cash is then put into tqqq. After crashing, the above formula assumes that TQQQ races higher in order to maintain it's long-term CAGR, so buying the dip helps a lot.

So generally speaking, keeping 30% in cash/bonds equals the result of 100% fully invested if you buy the dip. The downside is if there is no crash you will lag.

There are various tweaks like above to improve risk adjusted returns. It's not that hard to do if you have a basic knowledge of calc and stats.

There are a lot of assumptions in this comment, and solid math based on faulty assumptions is not going to be a good long-term strategy.

The markets are not predictable based on past history. Whenever you have a model that shows they are, you are either cherry-picking or have been lucky. Even more, there are far too many external phenomena affecting the fortunes of an individual company to be able to reliably make the kinds of bets you are taking about.

> After crashing, the above formula assumes that TQQQ races higher in order to maintain it's long-term CAGR, so buying the dip helps a lot.

This is the funniest assumption by far. All (public for profit) companies try to "race higher" at all times. Sometimes they succeed, sometimes they stagnate, sometimes they crash. Right after a crash is when you have the highest chance of it never coming back up. The CAGR is a historical observation, not some kind of parameter of a forward-looking model.

I think COVID is enough to disprove this idea. That was the bear market that turned bull ... for some sectors but not others. I don't think the cycles are predictable enough to make more profit (on average) than a buy the index strategy.

The highly mathematical quants hired by trading firms are doing something pretty different. They are trying to find opportunities for profit wherever they exist using advanced techniques. It is much different to you or me casually using what seems like a "common sense" approach. Most people who say "of course it will..." find that the next quarter is the exception to their definite rule about how everything works.

One of the funds you list is leveraged 3x. If the market drops 33% you're wiped out, get liquidated, and can never recover.

You've already made the assumption that you can detect the market bottom to select when to drop the $3K, which is ludicrous, and begs the question if you're know where the bottom is why not put the full $10K in then with maximum upward leverage.

I increased my crypto account 50x since the start of Covid. But I’m not delusional enough to think there was any skill involved in that. I was simply the beneficiary of an unprecedented macro environment.

You are likely the same, though you don’t know it.

Now if you manage to grow your portfolio 5x again between 2022 and 2024, that will be something.

> I increased my account by 5x since the lows of covid to present with simple large cap tech and etf strategies (...)

You managed to make money on a levered high-beta strategy in a zero interest rate environment? If you don't know who the rube is in a market, it's you. Add a bit of volatility and the smart kids at Jane Street will eat your portfolio. They are on both sides of every trade, taking your money no matter what you do.

The days of the "good track record" traders in the public markets have been over for 15 years. Forget your strategies, park your money in SPX and thank me later.

Please don't be a jerk in HN comments, regardless of how little someone else knows or you feel they do.

You can make your substantive points without that.

https://news.ycombinator.com/newsguidelines.html

Sooooo hard to get hired here. I’m convinced it’s impossible without a referral or something

They'd be silly to not interview someone who applied with strong quantitative background. Once you make the interview, it's all up to you. No amount of referrals will make up for a poor interview.

As I posted above.. I have family who work there. They were not a "referral or something".

I also worked at a hedge fund myself, and i was not a "referral" either.

They post positions online, apply. if you have the skills they are looking for you can get in.

The interviews are definitely hard, but I can confirm the recruiters will reach out to you directly if they find your profile interesting.

Sounds reasonable. In the past I applied for an internship and got resume rejected for swe, they seem rather elusive…

I know a couple of people working at hedge funds. Both on them just applied to a job posting and got hired without knowing anyone.

Are you talking about a trading role or an engineering role?

engineering

No it's not, but it is impossible with that attitude.

> Sooooo hard to get hired here.

Did you apply and get rejected?

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