evanpw

5 ms·

1.
by evanpw 3y ago
Yes, "same shape" in this context means "isometric". Rotations and reflections are considered differences in the way the shape is placed into the plane, not differences in the shape itself.
2.
by evanpw 4y ago
The same feed that publishes trades also publishes trade busts, so it's up to whoever's consuming it downstream to take care of.
3.
by evanpw 4y ago
The trades were not annulled, because NYSE ruled them not "clearly erroneous". Which is why it is was an existential mistake, not just an embarrassing one.
4.
by evanpw 4y ago
I had the same question while reading. It's probably obvious to the startup crowd, which is why it wasn't made explicit, but I think the trick is this: a company which will never make a profit is (should be) worth zero, but a comp
5.
by evanpw 4y ago
This is true of almost everything in math. You learn some definitions and techniques in one class, and it doesn't all become clear what's going on until you've used those to as the base layer for solving some other problems i
6.
by evanpw 4y ago
> Headlines about Supreme Court cases are almost uniformly misleading, because they suggest the Court is making decisions on policy issues rather than legal issues. I agree with this completely, but it doesn't help when justices beg
7.
by evanpw 4y ago
That's not it at all. All parties agreed that Congress passed a law allowing the EPA to regular carbon emissions by setting emission limits on different types of power plants based on the best current technology available for emission
8.
by evanpw 4y ago
A finance billionaire with a background in math and physics (Jim Simons)
9.
by evanpw 5y ago
If you're talking about the FDIC, that protects you only in the case that the bank fails. It doesn't have anything to do with fraud against you in particular.
10.
by evanpw 5y ago
A company being fined for failing to surveil employees' personal email and text messages would get very different comments here if it wasn't a bank.
11.
by evanpw 5y ago
That's exactly what they did. The article says $172m disgorgement (how much the CFTC thinks they profited from this), $311m restitution (the amount the CFTC thinks JPM harmed others but didn't capture), and $436m civil penalty (&q
12.
by evanpw 5y ago
Another insane fact: in the US, circumcisions are usually done by obstetricians. Doctors who are trained on and work on exclusively women, except for a single surgical procedure on newborn male babies.
13.
by evanpw 5y ago
Medallion distributes their earnings and stays a fixed size rather than compounding, so it's a category error to compare their returns to most hedge funds. (At 66% return for 30 years, they'd own everything in the world otherwise)
14.
by evanpw 5y ago
The difficulty is set so that almost all students can succeed, so this doesn't contradict anything the parent post said.
15.
by evanpw 6y ago
Pandas is still numpy under the hood, but you can create a numpy array that points to memory that was allocated elsewhere, so conversion to pandas can be done without copies in nice cases where the data model is the same (simple data type,
16.
by evanpw 6y ago
On Tuesday, GME traded more volume than any other stock, and that's on a day when the total market volume was much higher than usual (Wednesday is now the all-time record for share volume).
17.
by evanpw 6y ago
"An Introduction to Statistical Learning" was written by two of the same authors, and is explicitly meant to be a lower-level introduction to the same ideas: https://statlearning.com/ISLR%20Seventh%20Printing.pdf
18.
by evanpw 6y ago
Also highly recommend his book "Topology from the Differentiable Viewpoint". Or any of his books for that matter; he's a famously good mathematical writer.
19.
by evanpw 6y ago
Unix philosophy meaning tools that do one thing
20.
by evanpw 6y ago
I fear the alternative would be all the good names becoming heavily overloaded: https://en.wikipedia.org/wiki/Normal .
21.
by evanpw 6y ago
I think the duplicates are in the coordinate dimension, like x[1] having more than one value, rather than x[1] and x[2] have the same value.
22.
by evanpw 6y ago
Here's a long data analysis making that argument: https://randomcriticalanalysis.com/why-conventional-wisdom-o... .
23.
by evanpw 6y ago
Lots of exchanges have rate limits and messaging fees. And even if they don't, if you cause problems they'll shut you off.
24.
by evanpw 6y ago
The US population is more than 4x bigger than the UK, and seems to also have more police per capita, so those numbers would imply that policing is safer in the US. (Which I don't quite believe; more likely those assault numbers are inc
25.
by evanpw 6y ago
This should be easy to test, right? Look at the percentage of students admitted to Harvard whose parents went to Harvard vs. the percentage admitted whose parents went to some other similarly-selective school.
26.
by evanpw 6y ago
The contract is for a particular kind of crude delivered at a specific location. Most hedgers would still be better off closing the futures contract and taking the delivery they actually want instead.
27.
by evanpw 6y ago
Books that should be blog posts, papers that should be tweets.
28.
by evanpw 6y ago
The difference is that preventing new planes from entering the market doesn't kill people.
29.
by evanpw 7y ago
More precisely, you can back out an implied forecast of future volatility from options prices, and the VIX index is actually computed from the prices of options on the S&P 500 index; it's not just trailing realized volatility.
30.
by evanpw 7y ago
> If you expect volatility to increase If you have high confidence that volatility will increase more than the market expects it to. > buying options is a very safe bet There is no world in which buying options in a volatile single st

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