Medallion Fund “Stretches Explanation to the Limit,” Professor Claims

All "leveraged" ETFs (to the best of my knowledge) are synthetic - they achieve their "leverage" using derivatives, not by borrowing. These derivatives are not free, and like an option, can expire worthless. That's how the value in these ETFs evaporates over time, regardless of how the market performs.

Most of medaillon's returns are made with insider trading from hacking. The data science part is just come up with explanations that are complex enough and not easily disproven (e.g. find a correlating variable and explain that you had a magic algo that derived prediction from that correlating variable after the fact).

It's a perfect crime, but you would need to setup crazy incentive structures for all the team members and their immediate family to keep it secret... and that's what they are doing.

I would guess they used Russian hackers for the job, given that the fund is heavily funding Russian political interests in western countries.

I would recommend the SEC to dive really deep with appropriate expertise into this magic fund and double-check this simple theory of mine. Just for national security reasons alone.

(note again: this is a conspiracy theory and not evidence or fact-based)

If you look at AHL, they have lots of people who know the maths. They have their own institute at Oxford ffs (the number of people who don't have PHds from Oxbridge there is small), and they have crap performance, year-in, year-out.

It is a typical flaw of human nature to assume that when someone else does something extraordinary that they have some secret knowledge you don't. People on here talking about discrete topology and all kinds of craziness...read the book, one of the big early advantages that RenTech had was they sent some guy down to the Fed to transcribe by hand data that no-one else had. Another example is their stat arb strategy didn't work for years, until they worked out how to get good execution.

I am not saying that it is only this but if you read the book, there are several instances where RenTech try to apply something complex and it doesn't work...and the success they have is after doing something simple, marginally better than anyone else...again, to a certain kind of person, this simplicity is offensive but it is also why most people with technical backgrounds get destroyed by the market.

Also, one thing that is kind of unclear. Simons had almost nothing to do with the perf. By the early 90s, he wasn't personally active anymore (he was spending most of his time on venture capital). The step change was hiring Brown and Mercer (again, two guys who clearly knew the maths but had spent most of their time in industry). Ppl assume that Simons is in the boiler room doing all kinds of crazy technical stuff...he wasn't (most of the time that he ran the fund, it didn't do well at all).