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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.

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?”

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/

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.

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.

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.

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.

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.

I think neutrino detectors capture at best something like 10 neutrinos per year or so, so the throughput would be severely limited.

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

That's a maybe. Still, good point.

We already fire neutrino beams through the Earth's crust, and they travel at the speed of light, and the core isn't that much more dense.

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

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.

That’s why most markets close during night time.

No it isn’t.

Most markets, in terms of their daily volume, are open at night, but very thinly traded until EU hours, but some do see action in Asia hours. It’s just about liquidity.

Maybe you’re thinking of single name equity markets, which are a fraction of daily trading.

I think they’re probably asking about US markets. Afaik those do close at business hours and I’m not sure how after hours trading happens but it might not be available to most people.

I think the one of the main reasons is government concerns about shenanigans happen overnight without oversight / flash crash. That being said I presume all the breakers that would halt trading activity are probably automatic but potentially not all of them (I think the US did things like that during the housing collapse).

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

In theory having fewer repeaters improves latency, probably in the range of 100ns per repeater. I don't know how much of a practical effect that has, likely very minimal with modern implementations.

Either way it's more sensible to build high throughput microwave networks given the tiny amount of shortwave bandwidth we have.

I bet it's way lower than 100ms for this application. Single digits. Maybe less.

I wrote 100ns, and meant an analog repeater. Full digital regeneration is probably in the 1-10μs range.

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

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.

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.

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.

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!

This. Exactly this.

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.