tautologies are tautological

Trading in risk

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The excellent essay aggregator The Browser linked this week to an essay by Steve Randy Waldman on the relationship between freedom and risk. It’s an interesting piece and well worth reading. I want to instead talk about the blurb that The Browser wrote to recommend it:

Learned essay on the contradictions between freedom and risk. We almost all want freedom, but few of us want to carry the risks that go with freedom. The history of finance is the history of attempts to lay off or mitigate risk: all of which are doomed to failure. The risk has to accumulate somewhere. And, as in 2008, it eventually blows up.

I know I shouldn’t take this too seriously—it is, after all, just a little hook to encourage readers to click on the link—but I think there are a couple of important things to mention.

I am extensively on record that economics is not the same thing as finance, but of course they are related. Let’s say for the moment that if we can think of economics as being about the allocation of scarce resources, we can think of finance as being about the allocation of scarce capital or money. At the core of economic theory is the idea of mutually beneficial trade: it is possible that we can trade resources and both be better off than before. More than that: a trade willingly entered into by two parties with good information on the things being traded seems almost tautologically mutually beneficial. If it doesn’t benefit both, why do it?

Now of course “good information” is important. For example, when you sell me a used car knowing that it is in fact a few miles away from becoming kaput, I may later be upset. Similarly, in finance, if my information on the riskiness of an asset is bad, I may be sad later, and not just in the sense of being unlucky. But the claim that “all [attempts to lay off or mitigate risk] are doomed to failure” is very peculiar. There are two problems here. The easy one first: clearly not all risks “eventually blow up”. This is the point of risk! If all risks eventually come to pass, then surely they are not risks but racing certainties.

The second problem is that where the risk goes matters. Naturally “the risk has to accumulate somewhere”; we cannot magic away risk by passing it around. But where does it end up? Can the trade of a risky asset be mutually beneficial? Yes: if you are more willing to bear the risk than I am, then you will be willing to part with more to buy that risk than I am willing to accept to sell it. You can buy that risk from me—assume it for your own—and we can both be happier. Think of unemployment insurance: for me to lose my job may be catastrophic. I will be destitute; this risk is very costly for me to bear. For an insurance company, the risk that I lose my job is trivial. The insurance company is happy to absolve me of (some of) this risk, and I am happy to pay them a premium to do so. We are both happy. Dare I even say that my freedom is enhanced when I can trade risk in this way?

So yes, the risk accumulates. But the idea behind all trade is that we might be able to send resources to the place where they are most valuable. And so it is with risk: if we can trade risk, perhaps we can have it accumulate in the hands of those to whom it will be the most bearable. While we do not eliminate the risk, we minimize the pain that is caused if the bad outcomes happen. Hey presto!

Of course there is fraud and lies and bad information, and of course some risks can aggregate into systemic kerfuffles, but let’s not throw the baby out with the bathwater. Trade in risk is not an inherently destructive activity.

The received wisdom of ‘market capitalism’?

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I don’t know what to think of “Economics Does Not Lie” by Guy Sorman in the I-just-learned-it-existed City Journal. It’s reasonable and well-argued, even as it seems to push the buttons of the anti-economics set, and even as it seems to commit many of the same sins as those pesky “principles of economics“. The agenda seems to be a vigorous defense of the capitalist economy – almost too vigorous, with plenty of pro-America, anti-‘western Europe’ digs. Weird? Hold that thought.

In the meaty bit of the article, Sorman begins:

If economics is finally a science, what, exactly, does it teach? With the help of Columbia University economist Pierre-André Chiappori, I have synthesized its findings into ten propositions… The more the public understands and embraces these propositions, the more prosperous the world will become.

OK, so I’m interested; seems like what we have might be an alternative list of what Mankiw calls “principles” (I despair of ever actually getting a proper use of the word in this context). Sorman discusses them at length, but here’s the list:

1. The market economy is the most efficient of all economic systems.
2. Free trade helps economic development.
3. Good institutions help development.
4. The best measure of a good economy is its growth.
5. Creative destruction is the engine of economic growth.
6. Monetary stability, too, is necessary for growth; inflation is always harmful.
7. Unemployment among unskilled workers is largely determined by how much labor costs.
8. While the welfare state is necessary in some form, it isn’t always effective.
9. The creation of complex financial markets has brought about economic progress.
10. Competition is usually desirable.

First of all, I don’t disagree with the assertion that “almost all top economists—those who are recognized as such by their peers and who publish in the leading scientific journals—would endorse” this list, although that’s obviously verging on the tautology of the clique. As a list of the received wisdom, it’s not bad at all, then.

Nevertheless, though this is a relatively less noxious list than Mankiw’s ‘principles’, it can maybe be taken as received wisdom, but certainly not as axioms (not, to be clear, that Sorman makes any such claim). Where it fails, it fails because it suffers from the same diseases. What, for example, am I to make of the first one? Exactly what is the ‘market economy’ most efficient at achieving? Correct me if I’m wrong, but you can’t just be ‘efficient’ in and of itself, right?

Aside from these familiar complaints of mine, there are a couple of other things worth mentioning, most especially this claim:

Now only one economic system exists: market capitalism.

Not only untrue, but completely untrue. Just as no country has ever tried to implement a wholly communist allocation of resources, no country has ever tried to implement a wholly capitalist allocation of resources. The accurate statement would be that the “markets with government” hybrid system is the dominant one in the modern world – as I’ve talked about before. As Jeffrey Tucker at the Mises blog points out in his response to Sorman’s article, Sorman himself isn’t even talking about “market capitalism”, but about the hybrid system, which is further testament to its ubiquity.

Remember that thought we were holding? Here’s the very last line of the article:

His article was translated from the French by Ralph C. Hancock.

Might the agenda simply be a reflection of the precariousness of the ideology of markets in France? Not such an outlandish proposition…

Game theory often looks silly

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From Tim Harford’s blog:

“Game theorists know all about the centipede game:

One instance of the centipede game is as follows. A pile of $4 and a pile of $1 are lying on a table. Player I has two options, either to “stop” or to “continue.” If he stops, the game ends and he gets $4 while Player II gets the remaining dollar. If he continues, the two piles are doubled, to $8 and $2, and Player II is faced with a similar decision: either to take the larger pile ($8), thus ending the game and leaving the smaller pile ($2) for Player I, or to let the piles double again and let Player I decide. The game continues for at most six periods. If by then neither of the players have stopped, Player I gets $256 and Player II gets $64. Figure 1 depicts this situation. Although this game offers both players a very profitable opportunity, all standard game theoretic solution concepts predict that Player I will stop at the first opportunity, getting just $4.

Except, nobody really thinks this is the way players would behave in reality. The optimal strategy seems sociopathic; isn’t it worth playing cooperatively in the hope that the other player will do the same thing? (Unlike much real human interaction, standard game theory does not accomodate the “hope” that someone else will play suboptimally: optimal play is to be expected at all times. )”

Game theory is very clever and very useful, but often seems very naive. When it’s used in economics, it’s arguably the part of economics most hamstrung by the scattershot application of the “money=utility” fallacy. If you want your game theoretic result to be predictive or descriptively powerful, you must (must must) try really hard to make the payoffs reasonably accurate; in Harford’s quoted example the assumption is that the players care only about cash and that, as Harford says, they aren’t willing to take a shot on the other player prolonging the game. At the risk of being tautologically critical: can you read the setup of that game and not entertain the idea of waiting? I remember being taught the centipede game in David Myatt’s excellent game theory course as an undergrad; he showed us the ‘crazy centipede’ variant, which wondered exactly that: what chance of you choosing to continue the game is enough to make me also want to continue?

The kicker to me is that ‘game theoretic predictions’ are overwhelmingly often not as successful for the players as alternative strategies, even when we’re just measuring ‘success’ in the same cash-payoff terms as the theory. This is just what Harford goes on to describe:

But Ignacio Palacios-Huerta (best known to Undercover Economist readers as discovering that strikers and goalkeepers play optimal strategies in penalty-taking) and Oscar Volij gave the centipede game to skilled chess players. They found that the chess players were far more likely to play optimally; grandmasters always played optimally and took the $4. Hyper-rationality can be a disadvantage. (Or did the experiment discover something else: that chess grandmasters are sociopaths?) Palacios-Huerta and Volij don’t speculate. My guess is that they have discovered something about the rationality rather than morality or empathy of chess players, but I may be wrong.

It really does just beg for the ‘behavioral economics’ explosion: if predictions aren’t great, and in any case are less profitable than reality, we’re up the creek without a paddle or a boat.

Euphemisms

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It’s just semantics, but I wish there was an easy solution to the problem of using the word “economics” as a euphemism for real stuff. How unusual would it be for this story on General Motors’ headache-inducing losses to expire without a use of the word “economics” or “economy”? There’s actually only one:

“But the worsening economy in the United States led to higher fourth-quarter losses in the region: $1.1 billion, compared to $30 million in 2006.”

What does that mean? Does it mean “people are losing their jobs”? “There might be inflation going on”? “People are defaulting on their mortgages”? Seriously, if it means anything in itself, I don’t know what it is. I even looked up the word “economy”, and I think the definition that’s being implied is “the system or range of economic activity in a country, region, or community”: almost a perfect tautology.

That old writer’s maxim “show, don’t tell” should be, in my ideal world, applied to every use of the phrase “worsening economy”, “economic trends”, “the economy”, and all the others you can think of. They’re empty on two levels: structurally there’s the reflexive definition, but more importantly in a news story designed to inform, it obscures whatever the actual thing is.

Here’s another example:

“The Bank of England cut UK interest rates last week to 5.25% from 5.5% in an attempt to prevent a major slowdown in the economy.”

What does “major slowdown in the economy” mean? More unemployment? Less money for the common man? So help me, GDP? It surely can’t mean a “slowdown in the allocation of resources”, because that’s not a sentence. Show, don’t tell. Actually, the second example actually might be a step up from the first because it has the slightly less loaded “slowdown” rather than “worsening”. Don’t tell me how to feel when whatever you’re talking about happening happens!

Who is economic man?

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A provocative opening to this article attacking something called “economic man”:

“Myth: Homo economicus is a valid assumption of human behavior.
Fact: Homo economicus is a fiction useful to right-wing economists.”

“Economic man” would be too easy, of course; “Homo economicus” sounds more intellectual and somehow also more ridiculous. Anyway, if I pretend not to see the right-wing bit – what’s a right-wing economist? – I think the fact is a fact and the myth is a fact too, and not just because defining a “valid assumption” is not quite as obvious as it seems.

The essay is actually pretty interesting, though obviously normatively motivated. It goes on to say:

“Specifically, social scientists believe that human behavior is often complex, imperfect, limited, self-contradictory and unpredictable. Homo economicus, however, is a greatly simplified model which assumes that individuals possess the following traits:

* Perfect self-interest
* Perfect rationality
* Perfect information”

I love that “human behavior is…. unpredictable”; the logical conclusion of that argument would be to abandon all social science, would it not? Let’s take the long view and ignore that bit. Aside from that, as I’ve argued before, the perfect information trait has been scrutinized intently for a few decades, so it’s probably an obsolete criticism. The rationality bit is, again, untestable, since what we mean by rationality is that some pattern that’s to some degree predictable – whatever it might be – affects behavior.

The self-interest trait is the one that comes in for a lot of criticism, in the essay and generally. The most important myth to dispel right away is that “self-interest” means “cares only about things that materially affect me”; it means “cares only about things that I care about”, which is delightfully tautological and more innocuous. We have a special definition of “selfish”. I think what the critic really means is more in the spirit of the following, from Wikipedia (sorry):

“Economic man is also amoral, ignoring all social values unless adhering to them gives him utility. Some believe such assumptions about humans are not only empirically inaccurate but unethical.”

There are two problems with that: one is the use of “unethical”, which I’ll save for another day, and the second is methodological. It’s possible to write down a rational, self-interested “economic man” who will do anything. Literally anything can be “rationalized”; it’s meaningless to say that it’s “empirically inaccurate” to assume that “social values” give a person utility, because it’s impossible to empirically answer that question one way or another. Economists seeking accuracy would, methodologically, model a person who acted in accordance with social values as if that person got utility from conforming to social values. Our rational, self-interested man has magically developed a social conscience!

Later in the original article, the author says (in direct contradiction to their earlier claim that behavior is unpredictable, by the way):

“Biologists recognize four levels of survival: the gene, the individual, the group, and the specie. All of them interact to produce the complex and often paradoxical behavior we witness in humans. The error of Homo economicus is that it focuses only on one level: the individual. It cannot explain why couples bear children (to promote genetic survival), or why soldiers often sacrifice their lives in war (to promote group survival), or why people practice charity (to promote human survival).”

Again, I can only plead that we recognize that whatever economists do or are perceived to do, their method of modeling people can explain anything, and I mean that as both a criticism and a compliment. Our method is neutral, our method is empty. Attack the normative interpretation of our conclusions. Attack the assumptions we make. Don’t attack the method: you’re shooting at thin air.

Let’s do a thought experiment: imagine we had a super-supercomputer that could accommodate all the complexity we wanted, and imagine that our computer has also figured out how to perfectly model every single human being, and imagine that we believe it. Forget the fatalist implications and just ask: would an economist – who seeks to model choice and the allocation of scarce resources, to describe the world, to make predictions, and, ultimately, to inform – reject the computer? Would he reject the model? If he would, he is not a scientist: if the economist would reject it, then I’ll let all the critics of economics attack him, because surely the only way to justify rejection of that gift would be because the model would generate predictions that the economist didn’t like.

Economists should never make their “economic man” to suit their ideological goals. That’s not science. We must make our “economic man” realistic but clear, acknowledge what he does and does not do, what he does and does not embody. He can be anything we want: we are therefore powerful, and must then be honest, if nothing else.