Thursday, July 31, 2014

Strange Defeat

Following up on the previous post, below the fold is an article Arjun and I wrote last year for the Indian publication Economic and Political Weekly, on how liberal New Keynesian economists planted the seeds of their own defeat in the policy arena. 

I should add that Krugman is very far from the worst in this respect. If I criticize my soon-to-be colleague so much, it's only because of his visibility, and because the clarity of his writing and his genuinely admirable political commitments make it easier to see the constraints imposed by his theoretical commitments. You might say that his distinct virtues bring the common vices into sharper focus.

The Call Is Coming from Inside the House

Paul Krugman wonders why no one listens to academic economists. Almost all the economists in the IGM Survey agree that the 2009 stimulus bill successfully reduced unemployment and that its benefits outweighed its costs. So why are these questions still controversial?

One answer is that economists don’t listen to themselves. More precisely, liberal economists like Krugman who want the state to take a more active role in managing the economy, continue to teach  an economic theory that has no place for activist policy.

Let me give a concrete example.

One of Krugman’s bugaboos is the persistence of claims that expansionary monetary policy must lead to higher inflation. Even after 5-plus years of ultra-loose policy with no rising inflation in sight, we keep hearing that since so “much money has been created…, there should already be considerable inflation.” (That’s from exhibit A in DeLong’s roundup of inflationphobia.) As an empirical matter, of course, Krugman is right. But where could someone have gotten this idea that an increase in the money supply must always lead to higher inflation? Perhaps from an undergraduate economics class? Very possibly -- if that class used Krugman’s textbook.

Here’s what Krugman's International Economics says about money and inflation:
A permanent increase in the money supply causes a proportional increase in the price level’s long-run value. … we should expect the data to show a clear-cut positive association between money supplies and price levels. If real-world data did not provide strong evidence that money supplies and price levels move together in the long run, the usefulness of the theory of money demand we have developed would be in severe doubt. 
Sharp swings in inflation rates [are] accompanied by swings in growth rates of money supplies… On average, years with higher money growth also tend to be years with higher inflation. In addition, the data points cluster around the 45-degree line, along which money supplies and price levels increase in proportion. … the data confirm the strong long-run link between national money supplies and national price levels predicted by economic theory. 
Although the price levels appear to display short-run stickiness in many countries, a change in the money supply creates immediate demand and cost pressures that eventually lead to future increases in the price level. 
A permanent increase in the level of a country’s money supply ultimately results in a proportional rise in its price level but has no effect on the long-run values of the interest rate or real output. 

This last sentence is simply the claim that money is neutral in the long run, which Krugman continues to affirm on his blog. [1] The “long run” is not precisely defined here, but it is clearly not very long, since we are told that “Even year by year, there is a strong positive relation between average Latin American money supply growth and inflation.”

From the neutrality of money, a natural inference about policy is drawn:
Suppose the Fed wishes to stimulate the economy and therefore carries out an increase in the level of the U.S. money supply. … the U.S. price level is the sole variable changing in the long run along with the nominal exchange rate E$/€. … The only long-run effect of the U.S. money supply increase is to raise all dollar prices.
What is “the money supply”? In the US context, Krugman explicitly identifies it as M1, currency and checkable deposits, which (he says) is determined by the central bank. Since 2008, M1 has more than doubled in the US — an annual rate of increase of 11 percent, compared with an average of 2.5 percent over the preceding decade. Krugman’s textbook states, in  unambiguous terms, that such an acceleration of money growth will lead to a proportionate acceleration of inflation. He can hardly blame the inflation hawks for believing what he himself has taught a generation of economics students.

You might think these claims about money and inflation are unfortunate oversights, or asides from the main argument. They are not. The assumption that prices must eventually change in proportion to the central bank-determined money supply is central to the book’s four chapters on macroeconomic policy in an open economy. The entire discussion in these chapters is in terms of a version of the Dornbusch “overshooting” model. In this model, we assume that

1. Real exchange rates are fixed in the long run by purchasing power parity (PPP).
2. Interest rate differentials between countries are possible only if they are offset by expected changes in the nominal exchange rate.

Expansionary monetary policy means reducing interest rates here relative to the rest of the world. In a world of freely mobile capital, investors will hold our lower-return bonds only if they expect our nominal exchange rate to appreciate in the future. With the long-run real exchange rate pinned down by PPP, the expected future nominal exchange rate depends on expected inflation. So to determine what exchange rate today will make investors willing to holder our lower-interest bonds, we have to know how policy has changed their expectations of the future price level. Unless investors believe that changes in the money supply will translate reliably into changes in the price level, there is no way for monetary policy to operate in this model.

So  these are not throwaway lines. The more thoroughly a student understands the discussion in Krugman’s textbook, the stronger should be their belief that sustained expansionary monetary policy must be inflationary. Because if it is not, Krugman gives you no tools whatsoever to think about policy.

Let me anticipate a couple of objections:

Undergraduate textbooks don’t reflect the current state of economic theory. Sure, this is often true, for better or worse. (IS-LM has existed for decades only in the Hades of undergraduate instruction.) But it’s not much of a defense, is it? If Paul Krugman has been teaching his undergraduates economic theory that produces disastrous results when used as a guide for policy, you would think that would provoke some soul-searching on his part. But as far as I can tell, it hasn’t. But in this case I think the textbook does a good job summarizing the relevant scholarship. The textbook closely follows the model in Dornbusch’s Expectations and Exchange Rate Dynamics, which similarly depends on the assumption that the price level changes proportionately with the money supply. The Dornbusch article is among the most cited in open-economy macroeconomics and international finance, and continues to appear on international finance syllabuses in most top PhD programs.

Everything changes at the zero lower bound. Defending the textbook on the ground that it's pre-ZLB effectively concedes that what economists were teaching before 2008 has become useless since then. (No wonder people don’t listen.) If orthodox theory as of 2007 has proved to be all wrong in the post-Lehmann world, shouldn’t that at least raise some doubts about whether it was all right pre-Lehmann? But again, that's irrelevant here, since I am looking at the 9th Edition, published in 2011. And it does talk about the liquidity trap — not, to be sure, in the main chapters on macroeconomic policy, but in a two-page section at the end. The conclusion of that section is that while temporary increases in the money supply will be ineffective at the zero lower bond, a permanent increase will have the same effects as always: “Suppose the central bank can credibly promise to raise the money supply permanently … output will therefore expand, and the currency will depreciate.” (The accompanying diagram shows how the economy returns to full employment.) The only way such a policy might fail is if there is reason to believe that the increase in the money supply will subsequently be reversed. Just to underline the point, the further reading suggested on policy at the zero lower bound is an article by Lars Svennson that calls a permanent expansion in the money supply “the foolproof way” to escape a liquidity trap. There’s no suggestion here that the relationship between monetary policy and inflation is any less reliable at the ZLB; the only difference is that the higher inflation that must inevitably result from monetary expansion is now desirable rather than costly. This might help if Krugman were a market monetarist, and wanted to blame the whole Great Recession and slow recovery on bad policy by the Fed; but (to his credit) he isn’t and doesn’t.

Liberal Keynesian economists made a deal with the devil decades ago, when they conceded the theoretical high ground. Paul Krugman the textbook author says authoritatively that money is neutral in the long run and that a permanent increase in the money supply can only lead to inflation. Why shouldn't people listen to him, and ignore Paul Krugman the blogger?

[1] That Krugman post also contains the following rather revealing explanation of his approach to textbook writing:
Why do AS-AD? First, you do want a quick introduction to the notion that supply shocks and demand shocks are different ... and AS-AD gets you to that notion in a quick and dirty, back of the envelope way. 
Second — and this plays a surprisingly big role in my own pedagogical thinking — we do want, somewhere along the way, to get across the notion of the self-correcting economy, the notion that in the long run, we may all be dead, but that we also have a tendency to return to full employment via price flexibility. Or to put it differently, you do want somehow to make clear the notion (which even fairly Keynesian guys like me share) that money is neutral in the long run. That’s a relatively easy case to make in AS-AD; it raises all kinds of expositional problems if you replace the AD curve with a Taylor rule, which is, as I said, essentially a model of Bernanke’s mind.
This is striking for several reasons. First, Krugman wants students to believe in the "self-correcting economy," even if this requires teaching them models that do not reflect the way professional economists think. Second, they should think that this self-correction happens through "price flexibility." In other words, what he wants his students to look at, say, falling wages in Greece, and think that the problem must be that they have not fallen enough. That's what "a return to full employment via price flexibility" means. Third, and most relevant for this post, this vision of self-correction-by-prices is directly linked to the idea that money is neutral in the long run -- in other words, that a sustained increase in the money supply must eventually result in a proportionate increase in prices. What Krugman is saying here, in other words, is that a "surprising big" part of his thinking on pedagogy is how to inculcate the exact errors that drive him crazy in policy settings. But that's what happens once you accept that your job as an educator is to produce ideological fables.

Tuesday, July 15, 2014

Ancient Economists: Two Views

John Cochrane, reporting from the NBER Summer Institute:
The use of ancient quotations came up several times. I  complained a bit about Eggertsson and Mehrotra's long efforts to tie their work to quotes from verbal speculations of Keynes, Alvin Hansen, Paul Krugman and Larry Summers. Their rhetorical device is, "aha, these equations finally explain what some sage of 80 years ago or Important Person today really meant."  Ivan Werning really complained about this in Paul Beaudry's presentation. What does this complex piece of well worked out "21st century economics" have to do with long ago muddy debates between Keynes and Hayek? It stands on its own, or it doesn't. (In his view, it did, so why belittle it?) 
Physics does not write papers about "the Newton-Aristotle debate." Our papers should stand on their own too. They are right or wrong if they are logically coherent and describe the data, not if they fulfill the vague speculations of some sage, dead or alive. It's especially unhelpful to try to make this connection, I think, because the models differ quite sharply from the speculations of the sage. Alvin Hansen certainly did not think that a Taylor interest rate rule with a phi parameter greater than one was a central culprit in "secular stagnation." I haven't checked against the speech, but I doubt he thought that inflation would completely cure the problem in the first place. 
Sure, history of thought is important; tying ideas to their historical predecessors is important; recognizing the centuries of thinking on money and business cycles is important. But let's stand up for our own generation; we do not exist simply to finally put equations in the mouths of ancient economists. 
But, tying it all up, perhaps I'm just being an old fogey. Adam Smith wrote mostly words. Marx like Keynes wrote big complicated books that people spent a century writing about "this is what they really meant." Maybe models are at best quantitative parables. Maybe economics is destined to return to this kind of literary philosophy, not quantified science.
(via Suresh, who was also there.)

For the case in favor of ancient economists, here is Axel Leijonhufvud:
According to Sir Peter Medawar
A scientist's present thoughts and actions are of necessity shaped by what others have done and thought before him: they are the wave-front of a continuous secular process in which The Past does not have a dignified independent existence of its own. Scientific understanding is the integral of a curve of learning; science therefore in some sense comprehends its history within itself.
... Not every field of learning can claim to "comprehend its history within itself." For the current state of the art to be the "integral of past learning" in Medawar's sense, the collective learning process must be one that remembers everything of value and forgets only the errors and the false leads. But this requires the recognized capability to decide what is correct or true and what is in error or false. These decisions, moreover, must compel general assent. Once an answer is arrived at, it must be generally agreed to be the answer. The field must be one in which answers kill questions so definitively that the sense of alternative possibilities disappears. ... 
A science, or a subfield within it, may come to approximate these conditions because of its positive successes. But two other mechanisms that are not so nice will also be at work. First, the people in the field agree that certain questions, which they would have a hard time deciding, are somebody else's responsibility. So economics among the social sciences, like physics among the natural sciences, had first pick of problems and left the really hard ones, on which their methods did not give them a firm grip, for the younger sister disciplines to deal with as best they might. Second, the insiders to the field will agree to exclude some people who refuse to assent to the manner in which certain important questions have been settled. Both the exclusion of undecidable questions from the field of inquiry and the exclusion of undecided people from the professional group help to achieve collective concentration and intensive interaction within the group. … 
These reflections … offer some suggestions about when scientists might find the history of their field relevant and useful to current inquiry. One suggestion is to look for situations when a research program has bogged down, when anomalies have cropped up that cannot be reduced to or converted into ordinary puzzles within the paradigm. Another is to look for cases in which three conditions seem to be met:
a) certain central questions cannot be decided in a way that commands assent,
b) the (for the time being) undecidable questions cannot very well be left for somebody else to worry about, and
c) the people who withhold their assent from some popular suggested answer cannot be ignored or excommunicated.

... Economists are wont to reduce everything to choices. Economics itself develops through the choices that economists make. To use the past for present purposes, we should see the history of the field as sequences of decisions, of choices, leading up to the present. Imagine a huge decision tree, with its roots back in the time of Aristotle, and with the present generation of economists -- not all of them birds of a feather! -- twittering away at each other from the topmost twigs and branches. 
The branching occurs at points where economists have parted company, where problematic decisions had to be made but could not be made so as to command universal assent. The two branches need not be of equal strength at all; in many cases, universal agreement is eventually reached ex post so that one branch eventually dies and falls away. The oldest part of the tree is, perhaps, just the naked trunk; but the sap still runs in some surprising places. 
If you want to translate Medawar's image of science into my decision tree metaphor, you will have to imagine his sciences as fir trees -- with physics, surely, as the redwood – majestic things with tall, straight trunks and with live branches only at the very top. Economics, in contrast, would come out as a rather tangled, ill-pruned shrub … 
As long as "normal" progress continues to be made in these established directions, there is no need to reexamine the past … Things begin to look different if and when the workable vein runs out or, to change the metaphor, when the road that took you to the "frontier of the field" ends in a swamp or in a blind alley. A lot of them do. Our fads run out and we do get stuck occasionally. Reactions to finding yourself in a cul-de-sac differ. Tenured professors might often be content to accommodate themselves to it, spend their time tidying up the place, putting in a few modern conveniences, and generally improving the neighborhood. Braver souls will want out and see a tremendous leap of the creative imagination as the only way out -- a prescription, however, that will leave ordinary mortals just climbing the walls. Another way to go is to backtrack. Back there, in the past, there were forks in the road and it is possible, even plausible, that some roads were more passable than the one that looked most promising at the time. At this point, a mental map of the road network behind the frontier becomes essential.

Friday, July 4, 2014

The Rentier Would Prefer Not to Be Euthanized

Here’s another one for the “John Bull can stand many things, but he cannot stand two percent” files. As Krugman says, there's an endless series of these arguments that interest rates must rise. The premises are adjusted as needed to reach the conclusion. (Here's another.) But what are the politics behind it?

I think it may be as simple as this: The rentiers would prefer not to be euthanized. Under capitalism, the elite are those who own (or control) money. Their function is, in a broad sense, to provide liquidity. To the extent that pure money-holders facilitate production, it is because money serves as a coordination mechanism, bridging gaps — over time and especially with unknown or untrusted counterparties — that would otherwise prevent cooperation from taking place. [1] In a world where liquidity is abundant, this coordination function is evidently obsolete and can no longer be a source of authority or material rewards.

More concretely: It may well be true that markets for, say, mortgage-backed securities are more likely to behave erratically when interest rates are very low. But in a world of low interest rates, what function do those markets serve? Their supposed purpose is to make it easier for people to get home loans. But in a world of very low interest rates, loans are, by definition, easy to get. Again, with abundant liquidity, stocks may get bubbly. But in a world of abundant liquidity, what problem is the existence of stock markets solving? If anyone with a calling to run a business can readily start one with a loan, why support a special group of business owners? Yes, in a world where bearing risk is cheap, specialist risk-bearers are likely to go a bit nuts. But if risk is already cheap, why are we employing all these specialists?

The problem is, the liquidity specialists don’t want to go away. From finance’s point of view, permanently low interest rates are removing their economic reason for being — which they know eventually is likely to remove their power and privileges too. So we get all these arguments that boil down to: Money must be kept scarce so that the private money-sellers can stay in business.

It’s a bit like Dr. Benway in Naked Lunch:
“Now, boys, you won’t see this operation performed very often and there’s a reason for that…. You see it has absolutely no medical value. No one knows what the purpose of it originally was or if it had a purpose at all. Personally I think it was a pure artistic creation from the beginning. 
“Just as a bull fighter with his skill and knowledge extricates himself from danger he has himself invoked, so in this operation the surgeon deliberately endangers his patient, and then, with incredible speed and celerity, rescues him from death at the last possible split second….
Interestingly, Dr. Benway was worried about technological obsolescence too. “Soon we’ll be operating by remote control on patients we never see…. We’ll be nothing but button pushers,” etc. The Dr. Benways of finance like to fret about how robots will replace human labor. I wonder how much of that is a way of hiding from the knowledge that what cheap and abundant capital renders obsolete, is the capitalist?

EDIT: I'm really liking the idea of Larry Summers as Dr. Benway. It fits the way all the talk when he was being pushed for Fed chair was about how great he would be in a financial crisis. How would everyone known how smart he was -- how essential -- if he hadn't done so much to create a crisis to solve?

[1] Capital’s historic role as a facilitator of cooperation is clearly described in chapter 13 of Capital.

Thursday, July 3, 2014

Boulding on Interest

Kenneth Boulding, reviewing Maurice Allais's  Économie et intérêt in 1951:
Much work on the theory of interest is hampered at the start by its unquestioned assumption that "the" rate of interest, or even some complex of rates, is a suitable parameter for use in the construction of systems of economic relationships, whether static or dynamic. This is an assumption which is almost universally accepted and yet which seems to me to be very much open to question. My reason for questioning it is that the rate of interest is not an objective magnitude... The rate of interest is not a "price"; its dimensions are those of a rate of growth, not of a ratio of exchange, even though it is sometimes carelessly spoken of as a "price of loanable funds." What is determined in the market is not strictly the rate of interest but the price of certain "property rights." These may be securities, either stocks or bonds, or they may be items or collections of physical property. Each of these property rights represents to an individual an expected series of future values, which may be both positive and negative. If this expected series of values can be given some "certainty equivalent" ... then the market price of the property determines a rate of interest on the investment. This rate of interest, however, is essentially subjective and depends on the expectations of the individual; the objective phenomenon is the present market price... 
It is only the fact that the fulfilment of some expectations seems practically certain that gives us the illusion that there is an objective rate of interest determined in the market. But in strict theory there is no such certainty, even for gilt-edged bonds; and when the uncertainties of life, inflation, and government are taken into consideration, it is evident that this theoretical uncertainty is also a matter of practice. What is more, we cannot assume either that there are any "certain equivalents" of uncertain series for it is the very uncertainty of the future which constitutes its special quality. What this means is that it is quite illegitimate even to begin an interest theory by abstracting from uncertainty or by assuming that this can be taken care of by some "risk premium"; still less is it legitimate to construct a whole theory on these assumptions … without any discussion of the problems which uncertainty creates. What principally governs the desired structure of assets on the part of the individual is the perpetual necessity to hedge -- against inflation, against deflation, against the uncertainty in the future of all assets, money included. It is these uncertainties, therefore, which are the principal governors of the demand and supply of all assets without exception, and no theory which abstracts from these uncertainties can claim much significance for economics. Hence, Allais is attempting to do something which simply cannot be done, because it is meaningless to construct a theory of "pure" interest devoid of premiums for risk, liquidity, convenience, amortization, prestige, etc. There is simply no such animal. 
In other words: There are contexts when it is reasonable to abstract from uncertainty, and proceed on the basis that people know what will happen in the future, or at least its probability distribution. But interest rates are not such a context, you can't abstract away from uncertainty there. Because compensation for uncertainty is precisely why interest is paid.

The point that what is set in the market, and what we observe, is never an interest rate as such, but the price of some asset today in terms of money today, is also important.

Boulding continues:
The observed facts are the prices of assets of all kinds. From these prices we may deduce the existence of purely private rates of return. The concept of a historical "yield" also has some validity. But none of these things is a "rate of interest" in the sense of something determined in a market mechanism.  
This search for a black cat that isn't there leads Allais into several extended discussions of almost meaningless and self-constructed questions… Thus he is much worried about the "fact" that a zero rate of interest means an infinite value for land, land representing a perpetual income, which capitalized at a zero rate of interest yields an infinite value… This is a delightful example of the way in which mathematics can lead to an almost total blindness to economic reality. In fact, the income from land is no more perpetual than that from anything else and no more certain. … We might draw a conclusion from this that a really effective zero rate of interest in a world of perfect foresight would lead to an infinite inflation; but, then, perfect foresight would reduce the period of money turnover to zero anyway and would give us an infinite price level willy-nilly! This conclusion is interesting for the light it throws on the complete uselessness of the "perfect foresight" model but for little else. In fact, of course, the element which prevents both prices from rising to infinity and (private) money rates of interest from falling to zero is uncertainty - precisely the factor which Allais has abstracted from. Another of these quite unreal problems which worries him a great deal is why there is always a positive real rate of interest, the answer being of course that there isn't! … 
Allais reflects also another weakness of "pure"interest theory, which is a failure to appreciate the true significance and function of financial institutions and of "interest" as opposed to "profit" - interest in this sense being the rate of growth of value in "securities," especially bonds, and "profit" being the rate of growth of value of items or combinations of real capital. Even if there were no financial institutions or financial instruments ... there would be subjective expected rates of profit and historical yields on past, completed investments. In such a society, however, given the institution of private property, everyone would have to administer his own property. The main purpose of the financial system is to separate "ownership" (i.e., equity) from "control," or administration, that is, to enable some people to own assets which they do not control, and others to control assets which they do not own. This arrangement is necessitated because there is very little, in the processes by which ownership was historically determined through inheritance and saving, to insure that those who own the resources of society are … capable of administering them. Interest, in the sense of an income received by the owners of securities, is the price which society pays for correcting a defect in the otherwise fruitful institution of private property. It is, of course, desirable that the price should be as small as possible - that is, that there should be as little economic surplus as possible paid to nonadministering owners. It is quite possible, however, that this "service" has a positive supply price in the long run, and thus that, even in the stationary state, interest, as distinct from profit, is necessary to persuade the nonadministering owners to yield up the administration of their capital.
This last point is important, too. Property, we must always remember, is not a relationship between people and things. it is a relationship between people and people. Ownership of an asset means the authority to forbid other people from engaging in a certain set of productive activities. The “product” of the asset is how much other people will pay you not to exercise that right. Historically, of course, the sets of activities associated with a given asset have often been defined in relation to some particular means of production. But this need not be the case. In a sense, the patent or copyright isn’t an extension of the idea of property, but property in its pure form. And even where the rights of an asset owner are defined as those connected with some tangible object, the nature of the connection still has to be specified by convention and law.

According to Wikipedia, Économie et intérêt,  published in 1947, introduced a number of major ideas in macroeconomics a decade or more before the American economists they're usually associated with, including the overlapping generations model and the golden rule for growth. Boulding apparently did not find these contributions worth mentioning. He does, though, have something to say about Allais's “economic philosophy" which "is a curious combination of Geseel, Henry George and Hayek,” involving “free markets, with plenty of trust- and union-busting, depreciating currency, and 100 per cent reserves in the banking system, plus the appropriation of all scarcity rents and the nationalization of land.” Boulding describes this as “weird enough to hit the jackpot.” It doesn’t seem that weird to me. It sounds like a typical example of a political vision you can trace back to Proudhon and forward through the “Chicago plan” of the 1930s and its contemporary admirers to the various market socialisms and more or less crankish monetary reform plans. (Even Hyman Minsky was drawn to this strain of politics, according to Perry Mehrling's superb biographical essay.)What all these have in common is that they see the obvious inconsistency between capitalism as we observe it around us and the fairy tales of ideal market exchange, but they don’t reject the ideal. Instead, they propose a program of intrusive regulations to compel people to behave as they are supposed to in an unregulated market. They want to make the fairy tales true by legislation. Allais’ proposal for currency depreciation is not normally part of this package; it's presumably a response to late-1940s conditions in France. But other than that these market utopias are fairly consistent. In particular, it's always essential to reestablish the objectivity of money.

Finally, in a review full of good lines, I particularly like this one:
Allais's work is another demonstration that mathematics and economics, though good complements, are very imperfect substitutes. Mathematics can manipulate parameters once formulated and draw conclusions out which were already implicit in the assumptions. But skills of the mathematician are no substitute for the proper skill of the economist, which is that of selecting the most significant parameters to go into the system.