The Efficient Roulette Hypothesis

Nov 27 JDN 2459911

The efficient market hypothesis is often stated in several different ways, and these are often treated as equivalent. There are at least three very different definitions of it that people seem to use interchangeably:

  1. Market prices are optimal and efficient.
  2. Market prices aggregate and reflect all publicly-available relevant information.
  3. Market prices are difficult or impossible to predict.

The first reading, I will call the efficiency hypothesis, because, well, it is what we would expect a phrase like “efficient market hypothesis” to mean. The ordinary meaning of those words would imply that we are asserting that market prices are in some way optimal or near-optimal, that markets get prices “right” in some sense at least the vast majority of the time.

The second reading I’ll call the information hypothesis; it implies that market prices are an information aggregation mechanism which automatically incorporates all publicly-available information. This already seems quite different from efficiency, but it seems at least tangentially related, since information aggregation could be one useful function that markets serve.

The third reading I will call the unpredictability hypothesis; it says simply that market prices are very difficult to predict, and so you can’t reasonably expect to make money by anticipating market price changes far in advance of everyone else. But as I’ll get to in more detail shortly, that doesn’t have the slightest thing to do with efficiency.

The empirical data in favor of the unpredictability hypothesis is quite overwhelming. It’s exceedingly hard to beat the market, and for most people, most of the time, the smartest way to invest is just to buy a diversified portfolio and let it sit.

The empirical data in favor of the information hypothesis is mixed, but it’s at least plausible; most prices do seem to respond to public announcements of information in ways we would expect, and prediction markets can be surprisingly accurate at forecasting the future.

The empirical data in favor of the efficiency hypothesis, on the other hand, is basically nonexistent. On the one hand this is a difficult hypothesis to test directly, since it isn’t clear what sort of benchmark we should be comparing against—so it risks being not even wrong. But if you consider basically any plausible standard one could try to set for how an efficient market would run, our actual financial markets in no way resemble it. They are erratic, jumping up and down for stupid reasons or no reason at all. They are prone to bubbles, wildly overvaluing worthless assets. They have collapsed governments and ruined millions of lives without cause. They have resulted in the highest-paying people in the world doing jobs that accomplish basically nothing of genuine value. They are, in short, a paradigmatic example of what inefficiency looks like.

Yet, we still have economists who insist that “the efficient market hypothesis” is a proven fact, because the unpredictability hypothesis is clearly correct.

I do not think this is an accident. It’s not a mistake, or an awkwardly-chosen technical term that people are misinterpreting.

This is a motte and bailey doctrine.

Motte-and-bailey was a strategy in medieval warfare. Defending an entire region is very difficult, so instead what was often done was constructing a small, highly defensible fortification—the motte—while accepting that the land surrounding it—the bailey—would not be well-defended. Most of the time, the people stayed on the bailey, where the land was fertile and it was relatively pleasant to live. But should they be attacked, they could retreat to the motte and defend themselves until the danger was defeated.

A motte-and-bailey doctrine is an analogous strategy used in argumentation. You use the same words for two different versions of an idea: The motte is a narrow, defensible core of your idea that you can provide strong evidence for, but it isn’t very strong and may not even be interesting or controversial. The bailey is a broad, expansive version of your idea that is interesting and controversial and leads to lots of significant conclusions, but can’t be well-supported by evidence.

The bailey is the efficiency hypothesis: That market prices are optimal and we are fools to try to intervene or even regulate them because the almighty Invisible Hand is superior to us.

The motte is the unpredictability hypothesis: Market prices are very hard to predict, and most people who try to make money by beating the market fail.

By referring to both of these very different ideas as “the efficient market hypothesis”, economists can act as if they are defending the bailey, and prescribe policies that deregulate financial markets on the grounds that they are so optimal and efficient; but then when pressed for evidence to support their beliefs, they can pivot to the motte, and merely show that markets are unpredictable. As long as people don’t catch on and recognize that these are two very different meanings of “the efficient market hypothesis”, then they can use the evidence for unpredictability to support their goal of deregulation.

Yet when you look closely at this argument, it collapses. Unpredictability is not evidence of efficiency; if anything, it’s the opposite. Since the world doesn’t really change on a minute-by-minute basis, an efficient system should actually be relatively predictable in the short term. If prices reflected the real value of companies, they would change only very gradually, as the fortunes of the company change as a result of real-world events. An earthquake or a discovery of a new mine would change stock prices in relevant industries; but most of the time, they’d be basically flat. The occurrence of minute-by-minute or even second-by-second changes in prices basically proves that we are not tracking any genuine changes in value.

Roulette wheels are extremely unpredictable by design—by law, even—and yet no one would accuse them of being an efficient way of allocating resources. If you bet on roulette wheels and try to beat the house, you will almost surely fail, just as you would if you try to beat the stock market—and dare I say, for much the same reasons?

So if we’re going to insist that “efficiency” just means unpredictability, rather than actual, you know, efficiency, then we should all speak of the Efficient Roulette Hypothesis. Anything we can’t predict is now automatically “efficient” and should therefore be left unregulated.

Mind reading is not optional

Nov 20 JDN 2459904

I have great respect for cognitive-behavioral therapy (CBT), and it has done a lot of good for me. (It is also astonishingly cost-effective; its QALY per dollar rate compares favorably to almost any other First World treatment, and loses only to treating high-impact Third World diseases like malaria and schistomoniasis.)

But there are certain aspects of it that have always been frustrating to me. Standard CBT techniques often present as ‘cognitive distortions‘ what are in fact clearly necessary heuristics without which it would be impossible to function.

Perhaps the worst of these is so-called ‘mind reading‘. The very phrasing of it makes it sound ridiculous: Are you suggesting that you have some kind of extrasensory perception? Are you claiming to be a telepath?

But in fact ‘mind reading’ is simply the use of internal cognitive models to forecast the thoughts, behaviors, and expectations of other human beings. And without it, it would be completely impossible to function in human society.

For instance, I have had therapists tell me that it is ‘mind reading’ for me to anticipate that people will have tacit expectations for my behavior that they will judge me for failing to meet, and I should simply wait for people to express their expectations rather than assuming them. I admit, life would be much easier if I could do that. But I know for a fact that I can’t. Indeed, I used to do that, as a child, and it got me in trouble all the time. People were continually upset at me for not doing things they had expected me to do but never bothered to actually mention. They thought these expectations were “obvious”; they were not, at least not to me.

It was often little things, and in hindsight some of these things seem silly: I didn’t know what a ‘made bed’ was supposed to look like, so I put it in a state that was functional for me, but that was not considered ‘making the bed’. (I have since learned that my way was actually better: It’s good to let sheets air out before re-using them.) I was asked to ‘clear the sink’, so I moved the dishes out of the sink and left them on the counter, not realizing that the implicit command was for me to wash those dishes, dry them, and put them away. I was asked to ‘bring the dinner plates to the table’, so I did that, and left them in a stack there, not realizing that I should be setting them out in front of each person’s chair and also bringing flatware. Of course I know better now. But how was I supposed to know then? It seems like I was expected to, though.

Most people just really don’t seem to realize how many subtle, tacit expectations are baked into every single task. I think neurodivergence is quite relevant here; I have a mild autism spectrum disorder, and so I think rather differently than most people. If you are neurotypical, then you probably can forecast other people’s expectations fairly well automatically, and so they may seem obvious to you. In fact, they may seem so obvious that you don’t even realize you’re doing it. Then when someone like me comes along and is consciously, actively trying to forecast other people’s expectations, and sometimes doing it poorly, you go and tell them to stop trying to forecast. But if they were to do that, they’d end up even worse off than they are. What you really need to be telling them is how to forecast better—but that would require insight into your own forecasting methods which you aren’t even consciously aware of.

Seriously, stop and think for a moment all of the things other people expect you to do every day that are rarely if ever explicitly stated. How you are supposed to dress, how you are supposed to speak, how close you are supposed to stand to other people, how long you are supposed to hold eye contact—all of these are standards you will be expected to meet, whether or not any of them have ever been explicitly explained to you. You may do this automatically; or you may learn to do it consciously after being criticized for failing to do it. But one way or another, you must forecast what other people will expect you to do.

To my knowledge, no one has ever explicitly told me not to wear a Starfleet uniform to work. I am not aware of any part of the university dress code that explicitly forbids such attire. But I’m fairly sure it would not be a good idea. To my knowledge, no one has ever explicitly told me not to burst out into song in the middle of a meeting. But I’m still pretty sure I shouldn’t do that. To my knowledge, no one has ever explicitly told me what the ‘right of way’ rules are for walking down a crowded sidewalk, who should be expected to move out of the way of whom. But people still get mad if you mess up and bump into them.

Even when norms are stated explicitly, it is often as a kind of last resort, and the mere fact that you needed to have a norm stated is often taken as a mark against your character. I have been explicitly told in various contexts not to talk to myself or engage in stimming leg movements; but the way I was told has generally suggested that I would have been judged better if I hadn’t had to be told, if I had simply known the way that other people seem to know. (Or is it that they never felt any particular desire to stim?)

In fact, I think a major part of developing social skills and becoming more functional, to the point where a lot of people actually now seem a bit surprised to learn I have an autism spectrum disorder, has been improving my ability to forecast other people’s expectations for my behavior. There are dozens if not hundreds of norms that people expect you to follow at any given moment; most people seem to intuit them so easily that they don’t even realize they are there. But they are there all the same, and this is painfully evident to those of us who aren’t always able to immediately intuit them all.

Now, the fact remains that my current mental models are surely imperfect. I am often wrong about what other people expect of me. I’m even prepared to believe that some of my anxiety comes from believing that people have expectations more demanding than what they actually have. But I can’t simply abandon the idea of forecasting other people’s expectations. Don’t tell me to stop doing it; tell me how to do it better.

Moreover, there is a clear asymmetry here: If you think people want more from you than they actually do, you’ll be anxious, but people will like you and be impressed by you. If you think people want less from you than they actually do, people will be upset at you and look down on you. So, in the presence of uncertainty, there’s a lot of pressure to assume that the expectations are high. It would be best to get it right, of course; but when you aren’t sure you can get it right, you’re often better off erring on the side of caution—which is to say, the side of anxiety.

In short, mind reading isn’t optional. If you think it is, that’s only because you do it automatically.

Is the cure for inflation worse than the disease?

Nov 13 JDN 2459897

A lot of people seem really upset about inflation. I’ve previously discussed why this is a bit weird; inflation really just isn’t that bad. In fact, I am increasingly concerned that the usual methods for fixing inflation are considerably worse than inflation itself.

To be clear, I’m not talking about hyperinflationif you are getting triple-digit inflation or more, you are clearly printing too much money and you need to stop. And there are places in the world where this happens.

But what about just regular, ordinary inflation, even when it’s fairly high? Prices rising at 8% or 9% or even 11% per year? What catastrophe befalls our society when this happens?

Okay, sure, if we could snap our fingers and make prices all stable without cost, that would be worth doing. But we can’t. All of our mechanisms for reducing inflation come with costs—and often very high costs.

The chief mechanism by which inflation is currently controlled is open-market operations by central banks such as the Federal Reserve, the Bank of England, and the European Central Bank. These central banks try to reduce inflation by selling bonds, which lowers the price of bonds and reduces capital available to banks, and thereby increases interest rates. This also effectively removes money from the economy, as banks are using that money to buy bonds instead of lending it out. (It is chiefly in this odd indirect sense that the central bank manages the “money supply”.)

But how does this actually reduce inflation? It’s remarkably indirect. It’s actually the higher interest rates which prevent people from buying houses and prevent companies from hiring workers which result in reduced economic growth—or even economic recession—which then is supposed to bring down prices. There’s actually a lot we still don’t know about how this works or how long it should be expected to take. What we do know is that the pain hits quickly and the benefits arise only months or even years later.

As Krugman has rightfully pointed out, the worst pain of the 1970s was not the double-digit inflation; it was the recessions that Paul Volcker’s economic policy triggered in response to that inflation. The inflation wasn’t exactly a good thing; but for most people, the cure was much worse than the disease.

Most laypeople seem to think that prices somehow go up without wages going up, but that simply isn’t how it works. Prices and wages rise at close to the same rate in most countries most of the time. In fact, inflation is often driven chiefly by rising wages rather than the other way around. There are often lags between when the inflation hits and when people see their wages rise; but these lags can actually be in either direction—inflation first or wages first—and for moderate amounts of inflation they are clearly less harmful than the high rates of unemployment that we would get if we fought inflation more aggressively with monetary policy.

Economists are also notoriously vague about exactly how they expect the central bank to reduce inflation. They use complex jargon or broad euphemisms. But when they do actually come out and say they want to reduce wages, it tends to outrage people. Well, that’s one of three main ways that interest rates actually reduce inflation: They reduce wages, they cause unemployment, or they stop people from buying houses. That’s pretty much all that central banks can do.

There may be other ways to reduce inflation, like windfall profits taxes, antitrust action, or even price controls. The first two are basically no-brainers; we should always be taxing windfall profits (if they really are due to a windfall outside a corporation’s control, there’s no incentive to distort), and we should absolutely be increasing antitrust action (why did we reduce it in the first place?). Price controls are riskier—they really do create shortages—but then again, is that really worse than lower wages or unemployment? Because the usual strategy involves lower wages and unemployment.

It’s a little ironic: The people who are usually all about laissez-faire are the ones who panic about inflation and want the government to take drastic action; meanwhile, I’m usually in favor of government intervention, but when it comes to moderate inflation, I think maybe we should just let it be.

Now is the time for CTCR

Nov 6 JDN 2459890

We live in a terrifying time. As Ukraine gains ground in its war with Russia, thanks in part to the deployment of high-tech weapons from NATO, Vladimir Putin has begun to make thinly-veiled threats of deploying his nuclear arsenal in response. No one can be sure how serious he is about this. Most analysts believe that he was referring to the possible use of small-scale tactical nuclear weapons, not a full-scale apocalyptic assault. Many think he’s just bluffing and wouldn’t resort to any nukes at all. Putin has bluffed in the past, and could be doing so again. Honestly, “this is not a bluff” is exactly the sort of thing you say when you’re bluffing—people who aren’t bluffing have better ways of showing it. (It’s like whenever Trump would say “Trust me”, and you’d know immediately that this was an especially good time not to. Of course, any time is a good time not to trust Trump.)

(By the way, financial news is a really weird thing: I actually found this article discussing how a nuclear strike would be disastrous for the economy. Dude, if there’s a nuclear strike, we’ve got much bigger things to worry about than the economy. It reminds me of this XKCD.)

But if Russia did launch nuclear weapons, and NATO responded with its own, it could trigger a nuclear war that would kill millions in a matter of hours. So we need to be prepared, and think very carefully about the best way to respond.

The current debate seems to be over whether to use economic sanctions, conventional military retaliation, or our own nuclear weapons. Well, we already have economic sanctions, and they aren’t making Russia back down. (Though they probably are hurting its war effort, so I’m all for keeping them in place.) And if we were to use our own nuclear weapons, that would only further undermine the global taboo against nuclear weapons and could quite possibly trigger that catastrophic nuclear war. Right now, NATO seems to be going for a bluff of our own: We’ll threaten an overwhelming nuclear response, but then we obviously won’t actually carry it out because that would be murder-suicide on a global scale.

That leaves conventional military retaliation. What sort of retaliation? Several years ago I came up with a very specific method of conventional retaliation I call credible targeted conventional response (CTCR, which you can pronounce “cut-core”). I believe that now would be an excellent time to carry it out.

The basic principle of CTCR is really quite simple: Don’t try to threaten entire nations. A nation is an abstract entity. Threaten people. Decisions are made by people. The response to Vladimir Putin launching nuclear weapons shouldn’t be to kill millions of innocent people in Russia that probably mean even less to Putin than they do to us. It should be to kill Vladimir Putin.

How exactly to carry this out is a matter for military strategists to decide. There are a variety of weapons at our disposal, ranging from the prosaic (covert agents) to the exotic (precision strikes from high-altitude stealth drones). Indeed, I think we should leave it purposefully vague, so that Putin can’t try to defend himself against some particular mode of attack. The whole gamut of conventional military responses should be considered on the table, from a single missile strike to a full-scale invasion.

But the basic goal is quite simple: Launching a nuclear weapon is one of the worst possible war crimes, and it must be met with an absolute commitment to bring the perpetrator to justice. We should be willing to accept some collateral damage, even a lot of collateral damage; carpet-bombing a city shouldn’t be considered out of the question. (If that sounds extreme, consider that we’ve done it before for much weaker reasons.) The only thing that we should absolutely refuse to do is deploy nuclear weapons ourselves.

The great advantage of this strategy—even aside from being obviously more humane than nuclear retaliation—is that it is more credible. It sounds more like something we’d actually be willing to do. And in fact we likely could even get help from insiders in Russia, because there are surely many people in the Russian government who aren’t so loyal to Putin that they’d want him to get away with mass murder. It might not just be an assassination; it might end up turning into a coup. (Also something we’ve done for far weaker reasons.)


This is how we preserve the taboo on nuclear weapons: We refuse to use them, but otherwise stop at nothing to kill anyone who does use them.

I therefore call upon the world to make this threat:

Launch a nuclear weapon, Vladimir Putin, and we will kill you. Not your armies, not your generals—you. It could be a Tomahawk missile at the Kremlin. It could be a car bomb in your limousine, or a Stinger missile at Aircraft One. It could be a sniper at one of your speeches. Or perhaps we’ll poison your drink with polonium, like you do to your enemies. You won’t know when or where. You will live the rest of your short and miserable life in terror. There will be nowhere for you to hide. We will stop at nothing. We will deploy every available resource around the world, and it will be our top priority. And you will die.

That’s how you threaten a psychopath. And it’s what we must do in order to keep the world safe from nuclear war.