Hacker News: TaylorPhebillo

New comment by TaylorPhebillo in "The microstructure of wealth transfer in prediction markets"

TaylorPhebillo — Mon, 19 Jan 2026 17:18:03 +0000

How do prediction markets account for interest rates? I feel like I should be willing to pay no more than ~96 cents for a contract that will definitely resolve to a dollar in a year. Who puts up the other 4 cents?

New comment by TaylorPhebillo in "Clark County Election Analysis"

TaylorPhebillo — Mon, 10 Feb 2025 01:49:38 +0000

I'm sincerely unclear- is the analysis here that smaller samples (fewer ballots processed by a tabulator) have a higher relative standard deviation than larger samples?

New comment by TaylorPhebillo in "Jane Street raked in $4.4B at start of 2024"

TaylorPhebillo — Thu, 18 Apr 2024 02:46:22 +0000

Occasionally but pretty rarely. By the time a trade has become actually risk free, as in "I can instantly buy X here and sell X there and make a profit", someone will have realized that and done the trade when it was almost risk free- the that the price is likely but not guaranteed to go up there- and made the trade first.

New comment by TaylorPhebillo in "Jane Street raked in $4.4B at start of 2024"

TaylorPhebillo — Thu, 18 Apr 2024 02:42:57 +0000

Almost always outside of crypto, the market makers and exchanges are different entities. Exchanges maintain order books- who is willing to buy or sell what, at what prices, plus a lot of rules about tie breaking, order visibility, "implied" prices (e.g. sometimes the combination of two products is logically equivalent to a third), etc. When orders "cross"- that is, someone is offering to buy at a price at least as good as someone is willing to sell for, the exchanges matches those participants and they are considered to have traded (though for a mix of technical and regulatory reasons, the trade actually settles two days later)

Market makers generally maintain offers to both buy and sell a product, generally ~all the time the market is open. For example, they might offer to buy up to 30 X for $0.99 or sell up to 70 for $1.01. If small buy and sell orders come in more or less randomly, the market maker will sell about as many X as they buy, for (1.01 - 0.99) a profit of 2c for each set of orders. The trick for a market maker is to offer the best price, so that they get any orders at all, while accounting for the risk that the person buying or selling from them (the liquidity taker) isn't just a random order, but is either market moving or correctly predicting the market is about to move- e.g. a market maker offering to buy a million shares of a X at $0.99 will lose a lot of money to someone who correctly predicted X is about to go to $0.70, and took them up on the full offer.

New comment by TaylorPhebillo in "Ask HN: I am interested in reading about techniques HFT firms use"

TaylorPhebillo — Wed, 12 Jul 2023 17:49:11 +0000

These are still fairly canonical, and what I got recommended when I started recently. Trading at the Speed of Light by MacKenzie is very good too- a lighter read, but more recent.

New comment by TaylorPhebillo in "A person I consider trustworthy is convinced crypto will face a systemic risk"

TaylorPhebillo — Mon, 21 Nov 2022 02:39:31 +0000

I see [1] speculate that Coinbase users could be considered unsecured general creditors, and therefore lower priority to repay than secured creditors. That does seem bad on it's own. But nothing about equity investors having higher priority on funds. Is there some extra subtlety around e.g. shares being convertible into debt or something weird?

[1] https://www.bloomberg.com/news/articles/2022-05-11/coinbase-...

New comment by TaylorPhebillo in "For Best Results, Forget the Bonus"

TaylorPhebillo — Sun, 09 Oct 2022 19:24:07 +0000

Was this Amazon? Generally equity would replace the cash bonus in subsequent years. Compensation then becomes somewhat uncertain, but if it became a huge pay cut at that company and nowhere else, it seems expected that lots of employees would quit. That might be partially intentional.

New comment by TaylorPhebillo in "How Retail Investors Lose Money in Option Trading"

TaylorPhebillo — Thu, 08 Sep 2022 16:06:46 +0000

[Deleted a previous reply out of an abundance of caution about proprietary strategies]

That matches my first order academic understanding of market makers, but not the more detailed work I've read, or the work of the QRs at the handful of market makers I've spoken to/worked with.

It didn't seem like connecting trades were a particular focus of the people I've spoken with- is that something that happens off exchange? My understanding is that would happen automatically on the exchange, and that primarily market makers connect trades across time, pocketing bid/ask spreads but accepting risk of adverse price movements while they hold that position. To mitigate that risk, they do a bunch of signal analysis to set the spreads low enough to be competitive, high enough to mitigate that risk. Some market makers famously pay and provide price improvement for small/uncorrelated orders from retail brokers. I was told that that was specifically because of the reduced risk of adverse market movement from retail orders.

Market makers are generally required to always provide buy and sell prices, or risk fines/losing their market maker status on an exchange, right? Those prices might be extremely unreasonable (e.g. in a flash crash setting sell prices to 9999999), but if there's a market maker, there is required to be a price at which they will execute a trade, whether or not they can hedge that risk or now.

New comment by TaylorPhebillo in "How Retail Investors Lose Money in Option Trading"

TaylorPhebillo — Thu, 08 Sep 2022 00:19:17 +0000

That seems true, but in practice it seems like a market maker can't offer competitive spreads without having a decent sense of market direction, and they will have to take a position for at least a little while before closing out. So the line between a market maker and a trader who takes deliberate positions feels pretty fuzzy.

New comment by TaylorPhebillo in "U.S. annual inflation rate drops to 8.5%"

TaylorPhebillo — Wed, 10 Aug 2022 15:42:25 +0000

I'm not familiar with this, does this method require that each value is measured independently of the others? Because in that case, you'd want to use monthly inflation rates, rather than monthly estimates of inflation relative to 12 months prior, right?

New comment by TaylorPhebillo in "GitHub Copilot is generally available"

TaylorPhebillo — Tue, 21 Jun 2022 16:52:39 +0000

I've played with it a little bit:

Copilot did pretty poorly when I tried using it with Julia- it kept suggesting Python code. I suspect it would do something similar in Elixir.

I'm also a vim person who doesn't want to use VS code, but I've gotten more than enough value to get into my first IDE (with vim keybindings). A lot of tedious C++ code is getting correctly auto-generated.

New comment by TaylorPhebillo in "Imagen, a text-to-image diffusion model"

TaylorPhebillo — Tue, 24 May 2022 00:07:53 +0000

My hunch is that they aren't tailored toward ridiculous images exactly, but if they demonstrated "a woman sitting in a chair reading", it would be really hard to tell if the result was a small modification of an image in the training data. If they demonstrate "A snake made out of corn", I have less concern about the model having a very close training example.

New comment by TaylorPhebillo in "Intel's New Chimera: Alder Lake"

TaylorPhebillo — Sun, 15 May 2022 22:53:59 +0000

ARM big little uses the same instruction set on each core, right? You wouldn't have one 8.2 core and one 8.4 core?

New comment by TaylorPhebillo in "The death rate for children has dropped dramatically"

TaylorPhebillo — Thu, 28 Apr 2022 13:27:22 +0000

I hope so? But that's hard to study, and Givewell (in contrast to other effective altruism organizations) is fairly conservative about making claims and recommendations.

New comment by TaylorPhebillo in "The death rate for children has dropped dramatically"

TaylorPhebillo — Thu, 28 Apr 2022 01:37:36 +0000

The enormous risk factor from the article is malnutrition. Givewell, an organization which specializes in estimating the cost-effectiveness of forms of charitable giving, suggests treating acute malnutrition could be extremely cost effective, costing a few thousand dollars to save a life.

https://blog.givewell.org/2021/11/19/malnutrition-treatment/

New comment by TaylorPhebillo in "Ask HN: What tech companies/industries will do well in a recession?"

TaylorPhebillo — Wed, 27 Apr 2022 18:37:04 +0000

I'm not totally sure, but I suspect quantitate finance/market makers, of which tech is a big part, would do well during recessions- profits there seem correlated to volatility and volume of stock trading, which I'd guess would be high during a downturn and recovery?

New comment by TaylorPhebillo in "America’s Highest Earners and Their Taxes Revealed"

TaylorPhebillo — Tue, 26 Apr 2022 22:04:22 +0000

That makes some sense. So buy-borrow-die with all the shares used as collateral generates no taxes, if you can find someone to lend for the full value of the shares. I wonder how high a ratio you can borrow if you're e.g. Musk or Bezos.

On the off chance anyone finds this comment, I found this page with the current modification proposals helpful as well: https://crsreports.congress.gov/product/pdf/IF/IF11812?fbcli...

New comment by TaylorPhebillo in "What's new in CPUs since the 80s? (2015)"

TaylorPhebillo — Fri, 22 Apr 2022 23:13:32 +0000

I'm going through Understanding Software Dynamics by Richard Sites now, and it's the first book I've read that covers the practical performance implications of some of these new features, even if briefly.

New comment by TaylorPhebillo in "America’s Highest Earners and Their Taxes Revealed"

TaylorPhebillo — Wed, 13 Apr 2022 14:49:15 +0000

I'm still learning about buy-borrow-die, but US estate taxes are higher than income taxes above ~$12 million, right? Much less capital gains. So buy-borrow-die would generate more taxes than buy-sell-spend?

New comment by TaylorPhebillo in "How SoftBank’s costly bet on the ‘internet of things’ backfired at Arm"

TaylorPhebillo — Tue, 15 Feb 2022 02:15:49 +0000

I honestly can't tell how the Softbank vision fund is doing. News articles on it report record breaking profits and losses. The two vision funds were recently-ish reported as being worth $150b, but I can't tell what that translates to in annualized returns, or how that looks relative to the NASDAQ.