Finance as a Scale-Invariant Global Computer

Plus! The Market; Supply and Demand; The March Continues; ETFs; Intellectual Property

In this issue:

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The Diff April 7th 2025
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Finance as a Scale-Invariant Global Computer

The weekend after a big economic shift is an interesting time, because everyone's engaged in a two-track process:

  1. Now that things aren't moving quite so fast, it's possible to catch your breath and start thinking about how the world suddenly works, and perhaps to find some edge that other people have missed. On the other hand
  2. Everyone's going to show up at work on Monday having spent their weekend doing exactly the same thing, so there's a good chance that many of your insights will be priced in already, whether you were locking down container ships that can travel between a high-tariff nation and somewhere at the 10% tier or had figured out a new short position to put on.

Still, it's good to have breathing room, because decisions are qualitatively different when there isn't real-time feedback, and the more complex the decision is, the more likely it is that a little less feedback would help—if you used an AI-enhanced writing tool that gave you feedback word-by-word, it would probably make your quick work emails a bit better but it would make your novel a whole lot worse.[1] Some financial events get scheduled around this; the tariff announcement hit at 4pm, after the market was closed, so it would be somewhat expensive to trade in reaction to it and more prudent to digest a little longer (the original schedule for Tariff Day included a slot at 8pm for the market to react—it did!). Trading halts and limits are an ad hoc version of this: sometimes, the smartest thing for investors to do is take stock of the situation and be prevented from making expensive mistakes.

And this general intuition reveals something interesting and scale-invariant in finance: at every time scale, from high-frequency trading to direct investment in long-lived physical assets like airports and oil refineries, the fundamental question is always the same: at what point does a little more research pay off, compared to being the first to jump to a new conclusion.

In high-frequency trading, there's sometimes an assumption that companies use complex algorithms to make their trades. While there is plenty of complexity, it's not at the level of which trade to make—a typical complex algorithm would be something like "if the next tick in S&P futures is up, bid $0.01 more for SPY." There are more complex things than this, of course; your bid for SPY implies something about the optimal price for IBM, McDonald's, oil futures, etc. And you aren't reacting just to trades, but to order entry and order cancellation. But most of the time, the trading logic at these scales is painfully obvious: there's a broad supply/demand balance for asset classes, and the most liquid members of those asset classes are the first place where changes show up. The complexity comes in when you try to actually be the first person to do that, which means having the best answer to the question "what is the fastest way to transmit a small number of very important bits from a computer in Chicago, IL to one in Mahwah, NJ?”

At slower timescales, there's room for more sophisticated rules, but there's still a tradeoff. What's the right timeline to react to an earnings surprise? The moment of, after-hours, expensively? The next morning? Does that earnings surprise kick off a longer research project where you get context, and, if so, what are the odds that this context turns out to be roughly the same thing you were thinking the moment the market opened after that announcement, but it's now priced in? Equities have a volatility spike right at the same time they make a big announcement, but volatility stays elevated for a while as the market digests the news, and perhaps decides to refocus on something other than the headline variable.[2] Once you start acting, i.e. buying or selling before you're absolutely sure, a new consideration enters the equation: every trade is regrettable, because either you got the direction wrong or you could have done more size, and that tends to distort the rest of the research process. The slightly less-informed you of a day ago, a few hours ago, or even a few minutes ago is always an embarrassment to the current you, who is probably busy making an important financial decision.

This tradeoff between information quality and latency even shows up in the least liquid pockets of the market, whether that means buying infrastructure, making a venture investment, or a bank deciding whether or not to offer someone a credit card. In every case, it's almost always easy to articulate why one more month of data would make a big difference, and it's hard to measure the cost of waiting compared to the cost of acting decisively on necessarily incomplete information. So markets at all scales are engaged in a nonstop process of meta-cognition, continuously stress-testing their concept of what constitutes navel-gazing and what counts as shooting from the hip.

But the net result of that is that markets are always trying to think just hard enough to solve the problem at hand. And that has some interesting consequences. One thing it means is that when there's a correlated crash, the market's collective IQ drops. Not just because people are panicking, but because prices are the weighted average judgment of market participants, and when people are losing money for somewhat exogenous reasons—good trades held by highly-confident investors get cut fast because those investors are often levered—it often means that the smartest trades are being exited fastest.[3] But this is also partly a revelation that the market was not quite as smart as it had looked before, since one way markets go up is because a particular risk doesn’t materialize. If fading every Trump-driven selloff usually works, the people who do that will be a larger share of buying power over time. If Trump does something really drastic (hypothetically) they'll be the ones who have to sell the most, the fastest.

Traders are really in the communications business. They're constantly being given a task like this: here's one more incremental piece of information about the state of the world, now update the exchange rate between every pair of assets such that it best reflects this new information. They're also in the education business, but it's a process of continuous self-education on both the broad paradigm in which they're operating and the details of its mechanics. The longer a given market environment lasts, the higher the payoff from that within-regime optimization. Which means that at market turns, the biggest participants are the ones who are best prepared for a trading environment that no longer exists.


  1. There are some tasks, not just in the arts but in engineering, too, where the optimal result is a long uninterrupted stretch without distractions. The integrated circuit was invented partly because Jack Kilby had just started at Texas Instruments and hadn't accumulated enough vacation time to take a summer break. ↩︎

  2. Investors who care about fundamentals over fairly short timeframes will talk about what a stock "trades on," e.g. revenue growth versus free cash flow, or sometimes a company-specific performance indicator like subscriber count or even how quickly customers are adopting some new feature or pricing model. Sometimes, a multi-day earnings reaction is really a process of a stock ceasing to trade on one thing and starting to trade on another, like when a company that's celebrated for its rapid revenue growth suddenly has investors wondering if it'll ever make money. ↩︎

  3. In the end, there aren't that many assets—a couple dozen currencies that matter, a couple thousand stocks, most of which don't matter, etc. So "being smart" is a factor, and the better the economy is at putting the smartest people in the business of allocating capital, the more correlated their ideas will be, because they'll all be in the trades that anyone with enough IQ and data would be in. ↩︎

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Elsewhere

The Market

As of this writing, the S&P is down 13% YTD (as of the last-second round of editing, -11%—a refreshing pause). One of the interesting features of the current drawdown is that it's one bad day after another, not driven by marginal news flow but by its absence. And the reason for that is that historical crashes often have a dramatic response from the government, but that's a little tricky to engineer in the current situation. There is plenty of room for this, of course:

Supply and Demand

The bad news is that trillions of dollars of equity market cap has been vaporized, representing the output of countless jobs that will now not be done. The good news: a few billion dollars of equity supply won't be hitting the market just yet, since several high-profile IPOs have been pulled. This, of course, adds to the chronic problem that there's a backlog of large private companies whose original investors (or at least those investors' LPs) expected some liquidity by now. It's likely that many of today's unicorns will be permanently private, through a combination of acquisitions, attribution back to sub-unicorn status, and slowly shifting their capital base from pure equity VC to a debt/equity mix provided by PE or by some new hybrid category. Public markets make sense for many firms, but they have costs, and if companies don't want to pay those costs there's not a lot their investors can do about it.

The March Continues

Newsletters shouldn't fixate on temporarily exciting topics like tariffs when there are also continuously exciting ones like AI: Meta has shipped Llama 4, featuring, among other things, a model with a 10m-token context window (roughly enough for the complete works of Agatha Christie). Early reviews aren't great, and there are rumors that the model's stated benchmarks are cherry-picked, though, to be fair, there is almost always a complaint in this direction. The better models get, the harder it is to rigorously define a test that they can pass, outside of literal pass/fail domains like software and math. And even within those, the more skilled a model gets the more the relevant test of its limits is some kind of more subjective question, or at least a question whose answer only gets validated by how it performs in production. So the main lesson of this is that we're entering a period where it will be harder to know how well models do in advance, and where more of them will demonstrate their capabilities through the business results they produce than through their benchmarks.

Disclosure: long META.

ETFs

A new ETF, the Defiance MSTR Double Short Hedged ETF, plans to go short equal amounts of a MicroStrategy (now just "Strategy") 2x levered long and 2x levered short ETF. This strategy actually works over time, because the high volatility of these ETFs is a drag on returns. The problem is that it also works as a form of tail-risk insurance: if one of the positions does well enough for long enough, the other one compounds to zero while the winner can get arbitrarily high. So this is one of the classic adverse-selection offerings: it's a trade where the bull case is more obvious than the bear case, and the after-fee returns are not necessarily an adequate insurance premium for the risks taken. On the other hand, if investors are going to hear about volatility drag, and to try to exploit it, there's something to be said for packaging the trade in a single security, and having one fund centralize the otherwise tedious task of continuously rebalancing the bet.

Intellectual Property

The Minecraft movie has been a surprising hit so far, especially considering its mediocre reviews ($, WSJ). One reason is that audiences have apparently learned, through social media, to go absolutely crazy in response to particular catchphrases. There's a common coevolution between faster and slower kinds of media, where the fast media is harder to monetize upfront, but much faster at spreading ideas with low friction. And one of the ideas it can spread is that it's a good thing to consume some slower form of media. In the 2000s, the general form of this was bloggers writing books; in the later 2000s and early 2010s, long-form journalism going viral on short-form Twitter worked; BookTok has affected publishing, in at least some genres, by raising the odds that some random book will suddenly become a massive hit. In the long run, what this tends to do is to shift ad budgets towards the faster form of media, which means that the companies operating such platforms can invest more in features and eventually take more share of total time spent—new media options tend to be bad news for legacy players, but they give a little back along the way.