Archive for the 'Scott Sumner' Category

More on Arrow’s Explanatory Gap and the Milgrom-Stokey Argument

Published November 8, 2021 Kenneth Arrow , Nancy Stokey , No-trade theorem , Paul Milgrom , Scott Sumner 3 Comments

In my post yesterday, I discussed what I call Kenneth Arrow’s explanatory gap: the absence of any account in neoclassical economic theory of how the equilibrium price vector is actually arrived at and how changes in that equilibrium price vector result when changes in underlying conditions imply changes in equilibrium prices. I post below some revisions to several paragraphs in yesterday’s post supplemented by a more detailed discussion of the Milgrom-Stokey “no-trade theorem” and its significance. The following is drawn from a work in progress to be presented later this month at a conference celebrating the 150th anniversary of the publication of the Carl Menger’s Grundsätze der Volkswirtschaftslehre.

Thus, just twenty years after Arrow called attention to the explanatory gap in neoclassical theory by observing that neoclassical theory provides no explanation of how competitive prices can change, Paul Milgrom and Nancy Stokey (1982) turned Arrow’s argument on its head by arguing that, under rational expectations, no trading would ever occur at disequilibrium prices, because every potential trader would realize that an offer to trade at disequilibrium prices would not be made unless the offer was based on private knowledge and would therefore lead to a wealth transfer to the trader relying on private knowledge. Because no traders with rational expectations would agree to a trade at a disequilibrium price, there would be no incentive to seek or exploit private information, and all trades would occur at equilibrium prices.

This would have been a profound and important argument had it been made as a reductio ad absurdum to show the untenability of the rational-expectations as a theory of expectation formation, inasmuch as it leads to the obviously false factual implication that private information is never valuable and that no profitable trades are made by those possessed of private information. In concluding their paper, Milgrom and Stokey (1982) acknowledge the troubling implication of their argument:

Our results concerning rational expectations market equilibria raise anew the disturbing questions expressed by Beja (1977), Grossman and Stiglitz (1980), and Tirole (1980): Why do traders bother to gather information if they cannot profit from it? How does information come to be reflected in prices if informed traders do not trade or if they ignore their private information in making inferences? These questions can be answered satisfactorily only in the context of models of the price formation process; and our central result, the no-trade theorem, applies to all such models when rational expectations are assumed. (p. 17)

What Milgrom and Stokey seem not to have grasped is that the rational-expectations assumption dispenses with the need for a theory of price formation, inasmuch as every agent is assumed to be able to calculate what the equilibrium price is. They attempt to mitigate the extreme nature of this assumption by arguing that by observing price changes, traders can infer what changes in common knowledge would have implied the observed changes. That argument seems insufficient because any given change in price could be caused by more than one potential cause. As Scott Sumner has often argued, one can’t reason from a price change. If one doesn’t have independent knowledge of the cause of the price change, one can’t use the price change as a basis for further inference.

Krugman on Mr. Keynes and the Moderns

Published July 28, 2021 A. C. Pigou , D. H. Robertson , Frederick Lavington , gold standard , Gustav Cassel , Keynes , Paul Krugman , R. G. Hawtrey , Robert Barro , Scott Sumner , sticky prices , Uncategorized 10 Comments
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UPDATE: Re-upping this slightly revised post from July 11, 2011

Paul Krugman recently gave a lecture “Mr. Keynes and the Moderns” (a play on the title of the most influential article ever written about The General Theory, “Mr. Keynes and the Classics,” by another Nobel laureate J. R. Hicks) at a conference in Cambridge, England commemorating the publication of Keynes’s General Theory 75 years ago. Scott Sumner and Nick Rowe, among others, have already commented on his lecture. Coincidentally, in my previous posting, I discussed the views of Sumner and Krugman on the zero-interest lower bound, a topic that figures heavily in Krugman’s discussion of Keynes and his relevance for our current difficulties. (I note in passing that Krugman credits Brad Delong for applying the term “Little Depression” to those difficulties, a term that I thought I had invented, but, oh well, I am happy to share the credit with Brad).

In my earlier posting, I mentioned that Keynes’s, slightly older, colleague A. C. Pigou responded to the zero-interest lower bound in his review of The General Theory. In a way, the response enhanced Pigou’s reputation, attaching his name to one of the most famous “effects” in the history of economics, but it made no dent in the Keynesian Revolution. I also referred to “the layers upon layers of interesting personal and historical dynamics lying beneath the surface of Pigou’s review of Keynes.” One large element of those dynamics was that Keynes chose to make, not Hayek or Robbins, not French devotees of the gold standard, not American laissez-faire ideologues, but Pigou, a left-of-center social reformer, who in the early 1930s had co-authored with Keynes a famous letter advocating increased public-works spending to combat unemployment, the main target of his immense rhetorical powers and polemical invective.  The first paragraph of Pigou’s review reveals just how deeply Keynes’s onslaught had wounded Pigou.

When in 1919, he wrote The Economic Consequences of the Peace, Mr. Keynes did a good day’s work for the world, in helping it back towards sanity. But he did a bad day’s work for himself as an economist. For he discovered then, and his sub-conscious mind has not been able to forget since, that the best way to win attention for one’s own ideas is to present them in a matrix of sarcastic comment upon other people. This method has long been a routine one among political pamphleteers. It is less appropriate, and fortunately less common, in scientific discussion.  Einstein actually did for Physics what Mr. Keynes believes himself to have done for Economics. He developed a far-reaching generalization, under which Newton’s results can be subsumed as a special case. But he did not, in announcing his discovery, insinuate, through carefully barbed sentences, that Newton and those who had hitherto followed his lead were a gang of incompetent bunglers. The example is illustrious: but Mr. Keynes has not followed it. The general tone de haut en bas and the patronage extended to his old master Marshall are particularly to be regretted. It is not by this manner of writing that his desire to convince his fellow economists is best promoted.

Krugman acknowledges Keynes’s shady scholarship (“I know that there’s dispute about whether Keynes was fair in characterizing the classical economists in this way”), only to absolve him of blame. He then uses Keynes’s example to attack “modern economists” who deny that a failure of aggregate demand can cause of mass unemployment, offering up John Cochrane and Niall Ferguson as examples, even though Ferguson is a historian not an economist.

Krugman also addresses Robert Barro’s assertion that Keynes’s explanation for high unemployment was that wages and prices were stuck at levels too high to allow full employment, a problem easily solvable, in Barro’s view, by monetary expansion. Although plainly annoyed by Barro’s attempt to trivialize Keynes’s contribution, Krugman never addresses the point squarely, preferring instead to justify Keynes’s frustration with those (conveniently nameless) “classical economists.”

Keynes’s critique of the classical economists was that they had failed to grasp how everything changes when you allow for the fact that output may be demand-constrained.

Not so, as I pointed out in my first post. Frederick Lavington, an even more orthodox disciple than Pigou of Marshall, had no trouble understanding that “the inactivity of all is the cause of the inactivity of each.” It was Keynes who failed to see that the failure of demand was equally a failure of supply.

They mistook accounting identities for causal relationships, believing in particular that because spending must equal income, supply creates its own demand and desired savings are automatically invested.

Supply does create its own demand when economic agents succeed in executing their plans to supply; it is when, owing to their incorrect and inconsistent expectations about future prices, economic agents fail to execute their plans to supply, that both supply and demand start to contract. Lavington understood that; Pigou understood that. Keynes understood it, too, but believing that his new way of understanding how contractions are caused was superior to that of his predecessors, he felt justified in misrepresenting their views, and attributing to them a caricature of Say’s Law that they would never have taken seriously.

And to praise Keynes for understanding the difference between accounting identities and causal relationships that befuddled his predecessors is almost perverse, as Keynes’s notorious confusion about whether the equality of savings and investment is an equilibrium condition or an accounting identity was pointed out by Dennis Robertson, Ralph Hawtrey and Gottfried Haberler within a year after The General Theory was published. To quote Robertson:

(Mr. Keynes’s critics) have merely maintained that he has so framed his definition that Amount Saved and Amount Invested are identical; that it therefore makes no sense even to inquire what the force is which “ensures equality” between them; and that since the identity holds whether money income is constant or changing, and, if it is changing, whether real income is changing proportionately, or not at all, this way of putting things does not seem to be a very suitable instrument for the analysis of economic change.

It just so happens that in 1925, Keynes, in one of his greatest pieces of sustained, and almost crushing sarcasm, The Economic Consequences of Mr. Churchill, offered an explanation of high unemployment exactly the same as that attributed to Keynes by Barro. Churchill’s decision to restore the convertibility of sterling to gold at the prewar parity meant that a further deflation of at least 10 percent in wages and prices would be necessary to restore equilibrium.  Keynes felt that the human cost of that deflation would be intolerable, and held Churchill responsible for it.

Of course Keynes in 1925 was not yet the Keynes of The General Theory. But what historical facts of the 10 years following Britain’s restoration of the gold standard in 1925 at the prewar parity cannot be explained with the theoretical resources available in 1925? The deflation that began in England in 1925 had been predicted by Keynes. The even worse deflation that began in 1929 had been predicted by Ralph Hawtrey and Gustav Cassel soon after World War I ended, if a way could not be found to limit the demand for gold by countries, rejoining the gold standard in aftermath of the war. The United States, holding 40 percent of the world’s monetary gold reserves, might have accommodated that demand by allowing some of its reserves to be exported. But obsession with breaking a supposed stock-market bubble in 1928-29 led the Fed to tighten its policy even as the international demand for gold was increasing rapidly, as Germany, France and many other countries went back on the gold standard, producing the international credit crisis and deflation of 1929-31. Recovery came not from Keynesian policies, but from abandoning the gold standard, thereby eliminating the deflationary pressure implicit in a rapidly rising demand for gold with a more or less fixed total supply.

Keynesian stories about liquidity traps and Monetarist stories about bank failures are epiphenomena obscuring rather than illuminating the true picture of what was happening.  The story of the Little Depression is similar in many ways, except the source of monetary tightness was not the gold standard, but a monetary regime that focused attention on rising price inflation in 2008 when the appropriate indicator, wage inflation, had already started to decline.

Krugman and Sumner on the Zero-Interest Lower Bound: Some History of Thought

Published July 8, 2021 A. C. Pigou , Alfred Marshall , Earl Thompson , expected inflation , inflation , Keynes , Paul Krugman , Scott Sumner , Uncategorized 24 Comments
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UPDATE: Re-upping my post from July 8, 2011

I indicated in my first posting on Tuesday that I was going to comment on some recent comparisons between the current anemic recovery and earlier more robust recoveries since World War II. The comparison that I want to perform involves some simple econometrics, and it is taking longer than anticipated to iron out the little kinks that I keep finding. So I will have to put off that discussion a while longer. As a diversion, I will follow up on a point that Scott Sumner made in discussing Paul Krugman’s reasoning for having favored fiscal policy over monetary policy to lead us out of the recession.

Scott’s focus is on the factual question whether it is really true, as Krugman and Michael Woodford have claimed, that a monetary authority, like, say, the Bank of Japan, may simply be unable to create the inflation expectations necessary to achieve equilibrium, given the zero-interest-rate lower bound, when the equilibrium real interest rate is less than zero. Scott counters that a more plausible explanation for the inability of the Bank of Japan to escape from a liquidity trap is that its aversion to inflation is so well-known that it becomes rational for the public to expect that the Bank of Japan would not permit the inflation necessary for equilibrium.

It seems that a lot of people have trouble understanding the idea that there can be conditions in which inflation — or, to be more precise, expected inflation — is necessary for a recovery from a depression. We have become so used to thinking of inflation as a costly and disruptive aspect of economic life, that the notion that inflation may be an integral element of an economic equilibrium goes very deeply against the grain of our intuition.

The theoretical background of this point actually goes back to A. C. Pigou (another famous Cambridge economist, Alfred Marshall’s successor) who, in his 1936 review of Keynes’s General Theory, referred to what he called Mr. Keynes’s vision of the day of judgment, namely, a situation in which, because of depressed entrepreneurial profit expectations or a high propensity to save, macro-equilibrium (the equality of savings and investment) would correspond to a level of income and output below the level consistent with full employment.

The “classical” or “orthodox” remedy to such a situation was to reduce the rate of interest, or, as the British say “Bank Rate” (as in “Magna Carta” with no definite article) at which the Bank of England lends to its customers (mainly banks).  But if entrepreneurs are so pessimistic, or households so determined to save rather than consume, an equilibrium corresponding to a level of income and output consistent with full employment could, in Keynes’s ghastly vision, only come about with a negative interest rate. Now a zero interest rate in economics is a little bit like the speed of light in physics; all kinds of crazy things start to happen if you posit a negative interest rate and it seems inconsistent with the assumptions of rational behavior to assume that people would lend for a negative interest when they could simply hold the money already in their pockets. That’s why Pigou’s metaphor was so powerful. There are layers upon layers of interesting personal and historical dynamics lying beneath the surface of Pigou’s review of Keynes, but I won’t pursue that tangent here, tempting though it would be to go in that direction.

The conclusion that Keynes drew from his model is the one that we all were taught in our first course in macro and that Paul Krugman holds close to his heart, the government can come to the rescue by increasing its spending on whatever, thereby increasing aggregate demand, raising income and output up to the level consistent with full employment. But Pigou, whose own policy recommendations were not much different from those of Keynes, felt that Keynes had left out an important element of the model in his discussion. As a matter of logic, which to Pigou was as, or more important than, policy, an economy confronting Keynes’s day of judgment would not forever be stuck in “underemployment equilibrium” just because the rate of interest could not fall to the (negative) level required for full employment.

Rather, Pigou insisted, at least in theory, though not necessarily in practice, deflation, resulting from unemployed workers bidding down wages to gain employment, would raise the real value of the money supply (fixed in nominal terms in Keynes’s model) thereby generating a windfall to holders of money, inducing them to increase consumption, raising aggregate demand and eventually restoring full employment.  Discussion of the theoretical validity and policy relevance of what came to be known as the Pigou effect (or, occasionally, as the Pigou-Haberler Effect, or even the Pigou-Haberler-Scitovsky effect) became a really big deal in macroeconomics in the 1940s and 1950s and was still being taught in the 1960s and 1970s.

What seems remarkable to me now about that whole episode is that the analysis simply left out the possibility that the zero-interest-rate lower bound becomes irrelevant if the expected rate of inflation exceeds the putative negative equilibrium real interest rate that would hypothetically generate a macro-equilibrium at a level of income and output consistent with full employment.

If only Pigou had corrected the logic of Keynes’s model by positing an expected rate of inflation greater than the negative real interest rate rather than positing a process of deflation to increase the real value of the money stock, how different would the course of history and the development of macroeconomics and monetary theory have been.

One economist who did think about the expected rate of inflation as an equilibrating variable in a macroeconomic model was one of my teachers, the late, great Earl Thompson, who introduced the idea of an equilibrium rate of inflation in his remarkable unpublished paper, “A Reformulation of Macreconomic Theory.” If inflation is an equilibrating variable, then it cannot make sense for monetary authorities to commit themselves to a single unvarying target for the rate of inflation. Under certain circumstances, macroeconomic equilibrium may be incompatible with a rate of inflation below some minimum level. Has it occurred to the inflation hawks on the FOMC and their supporters that the minimum rate of inflation consistent with equilibrium is above the 2 percent rate that Fed has now set as its policy goal?

One final point, which I am still trying to work out more coherently, is that it really may not be appropriate to think of the real rate of interest and the expected rate of inflation as being determined independently of each other. They clearly interact. As I point out in my paper “The Fisher Effect Under Deflationary Expectations,” increasing the expected rate of inflation when the real rate of interest is very low or negative tends to increase not just the nominal rate, but the real rate as well, by generating the positive feedback effects on income and employment that result when a depressed economy starts to expand.

Welcome to Uneasy Money, aka the Hawtreyblog

Published July 5, 2021 Frederick Lavington , Keynes , Little Depression , Monetarism , R. G. Hawtrey , Say's Law , Scott Sumner , Uncategorized , Walras's Law 37 Comments
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UPDATE: I’m re-upping my introductory blog post, which I posted ten years ago toady. It’s been a great run for me, and I hope for many of you, whose interest and responses have motivated to keep it going. So thanks to all of you who have read and responded to my posts. I’m adding a few retrospective comments and making some slight revisions along the way. In addition to new posts, I will be re-upping some of my old posts that still seem to have relevance to the current state of our world.

What the world needs now, with apologies to the great Burt Bachrach and Hal David, is, well, another blog.  But inspired by the great Ralph Hawtrey and the near great Scott Sumner, I decided — just in time for Scott’s return to active blogging — to raise another voice on behalf of a monetary policy actively seeking to promote recovery from what I call the Little Depression, instead of the monetary policy we have now:  waiting for recovery to arrive on its own.  Just like the Great Depression, our Little Depression was caused mainly by overly tight money in an environment of over-indebtedness and financial fragility, and was then allowed to deepen and become entrenched by monetary authorities unwilling to commit themselves to a monetary expansion aimed at raising prices enough to make business expansion profitable.

That was the lesson of the Great Depression.  Unfortunately that lesson, for reasons too complicated to go into now, was never properly understood, because neither Keynesians nor Monetarists had a fully coherent understanding of what happened in the Great Depression.  Although Ralph Hawtrey — called by none other than Keynes “his grandparent in the paths of errancy,” and an early, but unacknowledged, progenitor of Chicago School Monetarism — had such an understanding,  Hawtrey’s contributions were overshadowed and largely ignored, because of often irrelevant and misguided polemics between Keynesians and Monetarists and Austrians.  One of my goals for this blog is to bring to light the many insights of this perhaps most underrated — though competition for that title is pretty stiff — economist of the twentieth century.  I have discussed Hawtrey’s contributions in my book on free banking and in a paper published years ago in Encounter and available here.  Patrick Deutscher has written a biography of Hawtrey.

What deters businesses from expanding output and employment in a depression is lack of demand; they fear that if they do expand, they won’t be able to sell the added output at prices high enough to cover their costs, winding up with redundant workers and having to engage in costly layoffs.  Thus, an expectation of low demand tends to be self-fulfilling.  But so is an expectation of rising prices, because the additional output and employment induced by expectations of rising prices will generate the demand that will validate the initial increase in output and employment, creating a virtuous cycle of rising income, expenditure, output, and employment.

The insight that “the inactivity of all is the cause of the inactivity of each” is hardly new.  It was not the discovery of Keynes or Keynesian economics; it is the 1922 formulation of Frederick Lavington, another great, but underrated, pre-Keynesian economist in the Cambridge tradition, who, in his modesty and self-effacement, would have been shocked and embarrassed to be credited with the slightest originality for that statement.  Indeed, Lavington’s dictum might even be understood as a restatement of Say’s Law, the bugbear of Keynes and object of his most withering scorn.  Keynesian economics skillfully repackaged the well-known and long-accepted idea that when an economy is operating with idle capacity and high unemployment, any increase in output tends to be self-reinforcing and cumulative, just as, on the way down, each reduction in output is self-reinforcing and cumulative.

But at least Keynesians get the point that, in a depression or deep recession, individual incentives may not be enough to induce a healthy expansion of output and employment. Aggregate demand can be too low for an expansion to get started on its own. Even though aggregate demand is nothing but the flip side of aggregate supply (as Say’s Law teaches), if resources are idle for whatever reason, perceived effective demand is deficient, diluting incentives to increase production so much that the potential output expansion does not materialize, because expected prices are too low for businesses to want to expand. But if businesses can be induced to expand output, more than likely, they will sell it, because (as Say’s Law teaches) supply usually does create its own demand.

[Comment after 10 years: In a comment, Rowe asked why I wrote that Say’s Law teaches that supply “usually” creates its own demand. At that time, I responded that I was just using “usually” as a weasel word. But I subsequently realized (and showed in a post last year) that the standard proofs of both Walras’s Law and Say’s Law are defective for economies with incomplete forward and state-contingent markets. We actually know less than we once thought we did!] 

Keynesians mistakenly denied that, by creating price-level expectations consistent with full employment, monetary policy could induce an expansion of output even in a depression. But at least they understood that the private economy can reach an impasse with price-level expectations too low to sustain full employment. Fiscal policy may play a role in remedying a mismatch between expectations and full employment, but fiscal policy can only be as effective as monetary policy allows it to be. Unfortunately, since the downturn of December 2007, monetary policy, except possibly during QE1 and QE2, has consistently erred on the side of uneasiness.

With some unfortunate exceptions, however, few Keynesians have actually argued against monetary easing. Rather, with some honorable exceptions, it has been conservatives who, by condemning a monetary policy designed to provide incentives conducive to business expansion, have helped to hobble a recovery led by the private sector rather than the government which  they profess to want. It is not my habit to attribute ill motives or bad faith to people whom I disagree with. One of the finest compliments ever paid to F. A. Hayek was by Joseph Schumpeter in his review of The Road to Serfdom who chided Hayek for “politeness to a fault in hardly ever attributing to his opponents anything but intellectual error.” But it is a challenge to come up with a plausible explanation for right-wing opposition to monetary easing.

[Comment after 10 years: By 2011 when this post was written, right-wing bad faith had already become too obvious to ignore, but who could then have imagined where the willingness to resort to bad faith arguments without the slightest trace of compunction would lead them and lead us.] 

In condemning monetary easing, right-wing opponents claim to be following the good old conservative tradition of supporting sound money and resisting the inflationary proclivities of Democrats and liberals. But how can claims of principled opposition to inflation be taken seriously when inflation, by every measure, is at its lowest ebb since the 1950s and early 1960s? With prices today barely higher than they were three years ago before the crash, scare talk about currency debasement and future hyperinflation reminds me of Ralph Hawtrey’s famous remark that warnings that leaving the gold standard during the Great Depression would cause runaway inflation were like crying “fire, fire” in Noah’s flood.

The groundlessness of right-wing opposition to monetary easing becomes even plainer when one recalls the attacks on Paul Volcker during the first Reagan administration. In that episode President Reagan and Volcker, previously appointed by Jimmy Carter to replace the feckless G. William Miller as Fed Chairman, agreed to make bringing double-digit inflation under control their top priority, whatever the short-term economic and political costs. Reagan, indeed, courageously endured a sharp decline in popularity before the first signs of a recovery became visible late in the summer of 1982, too late to save Reagan and the Republicans from a drubbing in the mid-term elections, despite the drop in inflation to 3-4 percent. By early 1983, with recovery was in full swing, the Fed, having abandoned its earlier attempt to impose strict Monetarist controls on monetary expansion, allowed the monetary aggregates to grow at unusually rapid rates.

However, in 1984 (a Presidential election year) after several consecutive quarters of GDP growth at annual rates above 7 percent, the Fed, fearing a resurgence of inflation, began limiting the rate of growth in the monetary aggregates. Reagan’s secretary of the Treasury, Donald Regan, as well as a variety of outside Administration supporters like Arthur Laffer, Larry Kudlow, and the editorial page of the Wall Street Journal, began to complain bitterly that the Fed, in its preoccupation with fighting inflation, was deliberately sabotaging the recovery. The argument against the Fed’s tightening of monetary policy in 1984 was not without merit. But regardless of the wisdom of the Fed tightening in 1984 (when inflation was significantly higher than it is now), holding up the 1983-84 Reagan recovery as the model for us to follow now, while excoriating Obama and Bernanke for driving inflation all the way up to 1 percent, supposedly leading to currency debauchment and hyperinflation, is just a bit rich. What, I wonder, would Hawtrey have said about that?

In my next posting I will look a little more closely at some recent comparisons between the current non-recovery and recoveries from previous recessions, especially that of 1983-84.

Defining Currency Manipulation for Scott Sumner

Published September 6, 2017 currency manipulation , exchange rate protection , Scott Sumner 15 Comments
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A little over a week ago, Scott Sumner wrote a post complaining that I had not yet given him a definition of currency manipulation. That complaint was a little bit surprising to me, because I have been writing about currency manipulation off and on for almost five years already on this blog (here’s my first, my second, and a more recent one). Now, in all modesty, I think some of those posts were pretty good and explained the concept of currency manipulation fairly clearly, so I’m not sure why Scott keeps insisting on the need for a definition. I am more than happy to accommodate him, but before doing so, I want to respond to some comments that he made in his post.

Scott began by quoting at length from my most recent post in which I responded to his criticism of my contention that China has in the past — but probably not the more recent past — engaged in currency manipulation. My basic argument – buttressed by an extended quotation from the world’s greatest living international-trade theorist, Max Corden — was that although nominal exchange rates are determined by monetary-policy choices, such as exchange-rate pegs or targets or nominal quantities of money, while real exchange rates are determined by real forces of resource endowments, technology, and consumer preferences, it is possible for monetary policy — either deliberately or inadvertently — to affect real exchange rates. This did not seem like a controversial argument to make, but Scott isn’t buying it.

Scott examines the following passage from my quotation of Corden:

A nominal devaluation will devalue the real exchange rate if there is some rigidity or sluggishness either in the prices of non-tradables or in nominal wages. The nominal devaluation will then raise the prices of tradables relative to wage costs and to labour-intensive non-tradables. Thus it protects tradables.

And he finds it wanting.

I can’t figure out what that means. Taken literally it seems to imply that a nominal depreciation that is associated with a real depreciation is a form of protectionism. But that’s obviously nonsense. So what is he claiming? We know the nominal exchange rate doesn’t matter; only the real rate matters. But currency manipulation can’t be just a depreciation in the real exchange rate, as real exchange rates move around for all sorts of reasons. If a revolution broke out in Indonesia tomorrow, I don’t doubt that the real value [of] their currency would plummet. But no one would accuse Indonesia of currency manipulation.

There is I think some confusion in the way Scott interprets what Corden said. Corden says that if monetary policy is used to depreciate the real exchange rate, then it may be that the monetary policy had a protectionist intent. Scott’s response is that there are many reasons why a real exchange rate could depreciate, and most of them have nothing to do with any protectionist intent. If there is a revolution in Indonesia, the Indonesian real exchange rate will depreciate. Scott asks whether Indonesian revolutionaries are currency manipulators. My answer is: not unless there is a plausible argument that the revolution was intended to cause the real exchange rate to depreciate, and that the a revolution is a moderately efficient way of benefitting those Indonesians who would gain from a depreciated exchange rate. I think it would be hard to make even a remotely plausible argument that starting a revolution would be a good way for Indonesian industrialists to capture the rents from their revolutionary protectionist strategy. But if Scott wants to make such an argument, I am willing to hear him out.

Scott considers another example.

How about a decline in the real exchange rate caused by government policy? Maybe, but I don’t recall anyone accusing the Norwegians of currency manipulation when they set up a sovereign wealth fund for their oil riches. That’s a government policy that encourages national saving and hence boosts the current account. Nor was Australia accused of currency manipulation when they did tax reform in the late 1990s.

OK, fair enough. There are government policies that can affect the real exchange rate. Is every government policy that reduces the real exchange rate protectionist? No. The reduction of the real exchange rate may be a by-product, an incidental consequence, of a policy adopted for reasons that have nothing to do with protectionism. The world is a complicated place to live in.

Then referring to a passage of mine in which I made a similar point, Scott comments.

The term ‘motive’ seems to play a role in the passage above:

If the motive for the real devaluation was to protect tradables, then the current account surplus will be only a by-product, leading to more accumulation of foreign exchange reserves than the country’s monetary authority really wanted. Alternatively, if the motive for the real devaluation was to build up the foreign-exchange reserves – or to stop their decline – then the protection of tradables will be the by-product.

Scott doesn’t like talking about “motives.”

As an economist, references to “motives” make me very uncomfortable. Let’s take the example of China. Did China’s government try to reduce the real value of the yuan because they saw what happened during the 1997 SE Asia crisis, and wanted a big war chest in case they faced a balance of payments crisis? Or did they do the weak yuan policy to shift resources from domestic industries to tradable goods industries? I have absolutely no idea, nor do I see why it matters. Surely if a concept of currency manipulation has any coherent meaning, it cannot depend on the motive of the policymakers in a particular country? We aren’t mind readers. This is especially true if we are to believe that currency manipulation hurts other countries, as its proponent seem to suggest. How will it be identified?

Scott is mixing up a lot of different issues here, so let me try to sort them out. There are indeed two plausible explanations for China’s vast accumulation of foreign-exchange reserves in the 1990s and in the 20 aughts. One is a precautionary build-up of foreign-exchange reserves to be available in the event of a financial crisis; the other is exchange-rate protection, aka currency manipulation. It’s true; we can’t read the minds of the policy makers, but we can make reasonable assessments of the relative plausibility of either hypothesis, based on the size of the accumulation, the policy steps that were taken to implement and facilitate the accumulation, the public pronouncements of relevant officials, and, if we had access to them, the internal documents upon which policy-makers relied in reaching their decisions. Now obviously, the Chinese government is not about to share their internal documents with me or any outside investigator, but that is a choice made by the Chinese, not some inherent deficiency in the evidence upon which a diligent researcher could potentially rely in making a determination about the motivation for Chinese policy decisions. As an economic historian of considerable accomplishment, Scott is well aware of the kind of evidence that is relevant to evaluating the motives of policy makers, so I can’t help but suspect that Scott is playfully engaging in a bit of rhetorical obfuscation here.

In the spirit of Bastiat, consider the following analogy. Suppose that for years we had been buying bananas from Colombia for 10 cents a pound. American consumers got to eat lots of cheap tasty fruit, which don’t grow well in non-tropical countries. Then in 2018, Trump sends a team of investigators down to Colombia, and finds out that we’ve been scammed. It’s actually not a warm country, indeed quite cool due to its high elevation. The Colombian government had spent millions building giant greenhouses to grow bananas. We’ve been tricked into buying all these cheap bananas from Colombia, which artificially created a “competitive advantage” in the banana industry through subsidies.

Here’s my question: Why does it matter why the Colombian bananas were cheap? If we benefited from buying the bananas at 10 cents a pound, why would we care if the price reflected true competitive advantage or government subsidy? Does the US benefit from buying 10-cent bananas, or not?

Once again, there’s some tactical diversion taking place. The question at hand is whether a protectionist policy could, in principle, be implemented through monetary policy. The answer is clearly yes. But Scott is now inviting us to consider a different question: Do protectionist policies adopted by one country adversely affect people in other countries. The answer is: it depends. Since there are no bananas grown in the US, export subsidies by the Colombian government to their banana growers would not harm any Americans. However, if there were US banana growers who had invested in banana trees and other banana-growing assets, there would be Americans harmed by the Colombian subsidies. It is possible that the gains to American banana consumers might outweigh the losses to American banana growers, but then there would have to be some comparison of the relative gains and losses.

Now Scott comes back to his demand for a definition.

But that’s not all. Even if you convinced me that we should worry about interventionist policies in our trading partners, I’d still want a definition of currency manipulation. There are a billion ways that a foreign government could influence a real exchange rate. Which ones are “manipulation”? It’s meaningless to talk about China depreciating its currency, without explaining HOW. A currency is just a price, and reasoning from a currency change (real or nominal) is simply reasoning from a price change. Which specific actions constitute currency manipulation? I don’t want motives, I need verifiable actions. And [why] does this concept have to involve a current account surplus? Australia’s been running CA deficits for as long as I can remember. Suppose the Aussie government did enough “currency manipulation” to reduce their trend CA deficit from 4% of GDP to 2% of GDP. But it was still a deficit. Would that be “manipulation”. Why or why not?

OK, here it is: currency manipulation occurs when a government/monetary authority sets a particular nominal exchange-rate target which, it believes, will, at current domestic prices, give its export- and import-competing industries a competitive advantage over their foreign competitors, thereby generating a current account surplus. In addition, to prevent the influx of foreign cash associated with current account surplus from raising domestic non-tradable prices and undermining the competitive advantage of the protected tradable-goods sector, the government/monetary authority either restricts the amount of base money created or, more likely, increases reserve requirements imposed on the banking system to create a persistent excess demand for money, thereby ensuring a continuing current account surplus and accumulation of foreign exchange reserves and preserving the protected position of the tradable-goods sector.

Scott continues:

Should we care why a country has a big CA surplus? Suppose Switzerland has a big CA surplus due to high private saving rates, Singapore has a big CA surplus due to high public saving in common stocks, and China has a CA surplus due to high public saving in foreign exchange. What difference does it make? (And I haven’t even addressed Ricardian equivalence, which further clouds these distinctions.)

Whether we should care or not care about exchange-rate protection is a question no different from whether we should care about protection by tariffs or quotas. There is an argument for unilateral free trade, but most of the post-World-War II trend toward (somewhat) freer trade has been predicated on the idea of reciprocal reductions in trade barriers. If we believe in the reciprocal reduction of trade barriers, then it is not unreasonable to be concerned about trade barriers that are erected through currency manipulation as a substitute for the tarrifs, import quotas, and export subsidies prohibited under reciprocal trade agreements. If Scott is not interested in reciprocal trade agreements, that’s fine, but it is not unreasonable for those who are interested in reciprocal trade agreements to be concerned about covertly protectionist policies that are imposed as substitutes for tariffs, import quotas, and export subsidies.

We know that the only way that governments can affect the real exchange rate is by enacting policies that impact national saving or national investment. But almost all policies impact either national saving or national investment. So which of those count as manipulation? Is it merely policies that lead to the accumulation of foreign exchange? If so, then won’t you simply encourage countries to use some other technique for boosting national saving? An alternative policy that avoids having them be labeled currency manipulators?

In principle, there could be other policies aimed at increasing national savings that are protectionist in intent. One would have to look at each possible instance and evaluate it. At least that’s what would have to be done if one believes in reciprocal trade agreements.

There were some other points that Scott mentioned in his post that I will not address now, because the hour is late and I’m getting tired. Perhaps I’ll follow up with a short follow-up post in a day or so. Not promising though.

What Is This Thing Called “Currency Manipulation?”

Published June 28, 2017 Bank of France , currency manipulation , exchange rate protection , Max Corden , Scott Sumner 12 Comments

Over the past few years, I have written a number of posts (e.g., here, here and here) posing — and trying to answer — the question: what is this strange thing called “currency manipulation?” I have to admit that I was actually moderately pleased with myself for having applied ideas developed by the eminent Australian international-trade and monetary economist Max Corden in a classic paper called “Exchange Rate Protection.” Unfortunately, my efforts don’t seem to have pleased – even minimally – Scott Sumner who, in a recent post in his Econlog blog, takes me to task for applying the term to China.

Now I get why Scott doesn’t like the term “currency manipulation.” The term is thrown around indiscriminately all the time as if its meaning were obvious. But the meaning is far from obvious. The term is also an invitation for demagogic abuse, which is another reason for being wary about using it.

A country can peg its exchange rate in terms of some other currency, or allow its exchange rate against all other currencies to float, or it can do a little of both, seeking to influence its exchange rate intermittently depending upon a variety of factors and objectives. A pegged exchange rate may be called a form of intervention (which is not — repeat not —  a synonym for “manipulation”), but if the monetary authority takes its currency peg seriously, it makes the currency peg the overriding determinant of its monetary policy. It is not the only element of its monetary policy, because the monetary authority has another policy objective that it can pursue simultaneously, namely, its holdings of foreign-exchange reserves. If the monetary authority adopts a tight monetary policy, it gains reserves, and if it adopts a loose policy it loses reserves. What constrains a monetary authority with a fixed-exchange rate in loosening policy is the amount of reserves that it is prepared to forego to maintain that exchange rate, and what constrains the monetary authority in tightening its policy is the interest income that must forego in accumulating non-interest-bearing, or low-interest-bearing, foreign-exchange reserves.

What distinguishes “currency manipulation” from mere “currency intervention?” Borrowing Max Corden’s idea of exchange-rate protection, I argued in previous posts that currency manipulation occurs when, in order to favor its tradable-goods sector (i.e., exporting and import-competing industries), a monetary authority (like the Bank of France in 1928) chooses an undervalued currency peg corresponding to a low real exchange rate, or intervenes in currency markets to reduce its nominal exchange rate, while tightening monetary policy to slow down the rise of domestic prices that normally follows a reduced nominal exchange rate. Corden points out that, as a protectionist strategy, exchange-rate protection is inferior to simply raising tariffs on imports or subsidizing exports. However, if international agreements make it difficult to raise tariffs and subsidize exports, exchange-rate protection may become the best available protectionist option.

In his post, “Nominal exchange rates, real exchange rates and protectionism,” Sumner denies that the idea of currency manipulation, and, presumably, the idea of exchange-rate protection make any sense. Here’s what Scott has to say:

The three concepts mentioned in the title of the post are completely unrelated to each other. So unrelated that the subjects ought not even be taught in the same course. The nominal exchange rate is a monetary concept. Real exchange rates belong in course on the real side of macro, perhaps including public finance. And protectionism belongs in a (micro) trade course.

The nominal exchange rate is the relative price of two monies. It’s determined by the monetary policies of the two countries in question. It plays no role in trade.

Scott often cites sticky prices as an important assumption of macroeconomics, so I don’t understand why he thinks that the nominal exchange rate has no effect on trade. If prices do not all instantaneously adjust to a change in the nominal exchange rate, changes in nominal exchange rates are also changes in real exchange rates until prices adjust fully to the new exchange rate.

Protectionism is a set of policies (such as tariffs and quotas) that drives a wedge between domestic and foreign prices. Protectionist policies reduce both imports and exports. They might also slightly affect the current account balance, but that’s a second order effect.

A protectionist policy causes resources from the non-tradable-goods sector to shift to the tradable-goods sector, favoring some domestic producers and disfavoring others, as well as favoring workers specialized to the tradable-goods sector. Whether it affects the trade balance depends on how the policy is implemented, so I agree that raising tariffs doesn’t automatically affect the trade balance. To determine whether and how the trade balance is affected, one has to make further assumptions about the distributional effects of the policy and about the budgetary and monetary policies accompanying the policy. Causation can go in either direction from real exchange rate to trade balance or from trade balance to real exchange rate.

In the following quotation, Scott ignores the relationship between the real exchange rate and the relative pricesof tradables and non-tradables. Protectionist policies, by increasing the relative price of tradables to non-tradables, shift resources from the non-tradable-goods to the tradable-goods sector. That’s the sense in which, contrary to Scott’s assertion, a low real-exchange rate makes enhances the competitiveness of one country relative to other countries. The cost of production in the domestic tradable-goods sector is reduced relative to the price of tradable goods, making the tradable-goods sector more competitive in the markets in which domestic producers compete with foreign producers. I don’t say that increasing the competitiveness of the domestic tradable-goods sector is a good idea, but it is not meaningless to talk about international competitiveness.

Real exchange rates influence the trade balance. When there is a change in either domestic saving or domestic investment, the real exchange rate must adjust to produce an equivalent change in the current account balance. A policy aimed at a bigger current account surplus is not “protectionist”, as it does not generally reduce imports and exports, nor does it drive a wedge between domestic and foreign prices. It affects the gap between imports and exports. . . .

A low real exchange rate is sometimes called a “competitive advantage”, although the concept has absolutely nothing to do with either competition or advantages. It’s simply a reflection of an imbalance between domestic saving and domestic investment. These imbalances also occur within countries, and no one ever worries about regional “deficits”. But for some odd reason at the national level they become a cause for concern. Some of this is based on the mercantilist fallacy that exports are good and imports are bad.

This is where Scott turns his attention to me.

Here’s David Glasner:

Currency manipulation has become a favorite bugbear of critics of both monetary policy and trade policy. Some claim that countries depress their exchange rates to give their exporters an unfair advantage in foreign markets and to insulate their domestic producers from foreign competition. Others claim that using monetary policy as a way to stimulate aggregate demand is necessarily a form of currency manipulation, because monetary expansion causes the currency whose supply is being expanded to depreciate against other currencies, making monetary expansion, ipso facto, a form of currency manipulation.

As I have already explained in a number of posts (e.g., here, here, and here) a theoretically respectable case can be made for the possibility that currency manipulation can be used as a form of covert protectionism without imposing either tariffs, quotas or obviously protectionist measures to favor the producers of one country against their foreign competitors.

I disagree with this. There is no theoretically respectable case for the argument that currency manipulation can be used as protectionism. But I would go much further; there is no intellectually respectable definition of currency manipulation.

Well, my only response is that I consider Max Corden to be just about the most theoretically-respectable economist alive. So let me quote at length from Corden’s essay “Macroeconomic and Industrial Policies” reprinted in his volume Protection, Growth and Trade (pp. 288-301)

There is clearly a relationship between macroeconomic policy and industrial policy on the foreign trade side. . . . The nominal exchange rate is an instrument of macroeconomic policy, while tariffs, import quotas, export subsidies and taxes and voluntary export restraints can all be regarded as instruments of industrial policy. Yet an exchange-rate change can have “industrial” effects. It therefore seems useful to clarify the relationship between exchange-rate policy and the various micro or industrial-policy instruments.

The first step is to distinguish a nominal from a real exchange-rate change and to introduce the concept of “exchange-rate protection. . . . If the exchange rate depreciates to the same extent as all costs and prices are rising (relative to costs and prices in other countries) there may be no real change at all. The nominal exchange rate is a monetary phenomenon, and it is possible that it is no more than that. A monetary authority may engineer a nominal devaluation designed to raise the domestic currency prices of exports and import-competing goods, and hence to benefit these industries. But if nominal wages quickly rise to compensate for the higher tradable-goods prices, no real effects – no rises in the absolute and relative profitability of tradable-goods industries – will remain. Monetary policy can influence the nominal-exchange rate, and possibly can even maintain it at a fixed value, but it cannot necessarily affect the real exchange rate. The real exchange rate refers to the relative price of tradable and non-tradable goods. While its absolute value is difficult to measure because of the ambiguity of the distinction between tradable and non-tradable goods, changes in it are usually – and reasonably – measured or indicated by relating changes in the nominal exchange rate to changes in some index of domestic prices or costs, or possibly to the average nominal wage level. This is sometimes called an index of competitiveness.

A nominal devaluation will devalue the real exchange rate if there is some rigidity or sluggishness either in the prices of non-tradables or in nominal wages. The nominal devaluation will then raise the prices of tradables relative to wage costs and to labour-intensive non-tradables. Thus it protects tradables. This is “exchange-rate protection”. It protects the whole group of tradables relative to non-tradables. It will tnd ot shift resources into tradables out of non-tradables and domestic demand in the opposite direction. If at the same time macroeconomic policy ensures a demand-supply balance for non-tradables – hence decreasing aggregate demand (absorption) in real terms appropriately – a balance of payments surplus (or at least a lesser deficit than before) will result. This refers to the balance of payments on current account since the concurrent fiscal and monetary policies can have varying effects on private capital inflow.

If the motive for the real devaluation was to protect tradables, then the current account surplus will be only a by-product, leading ot more accumulation of foreign exchange reserves than the country’s monetary authority really wanted. Alternatively, if the motive for the real devaluation was to build up the foreign-exchange reserves – or to stop their decline – then the protection of tradables will be the by-product.

The main point to make is that a real exchange-rate change has effects on the relative and absolute profitability of different industries, a real devaluation favouring tradables relative to non-tradables, and a real appreciation the opposite. A nominal exchange-rate change can thus serve an industrial-policy purpose, provided it can be turned into a real exchange-rate change and that the incidental effects on the balance of payments are accepted.

This does not mean that it is an optimal form of industrial policy. . . . [P]rotection policy could be directed more precisely to the industries to be protected, avoiding the by-product effect of an undesired balance-of-payments surplus; and in any case it can be argued that defensive protection policy is unlikely to be optimal, positive adjustment policy being preferable. Nevertheless, it is not difficult to find examples of countries that have practiced exchange-rate protection, if implicitly. They have intervened in the foreign-exchange market to prevent an appreciation of the exchange rate that might otherwise have taken place – or at least, they have “leaned against the wind.” – not because they really wanted to build up foreign-exchange reserves, but because they wanted to protect their tradable-goods industries – usually mainly their export industries.

Scott again quotes me and then comments:

And the most egregious recent example of currency manipulation was undertaken by the Chinese central bank when it effectively pegged the yuan to the dollar at a fixed rate. Keeping its exchange rate fixed against the dollar was precisely the offense that the currency-manipulation police accused the Chinese of committing.

Because currency manipulation does not exist as a coherent concept, I don’t see any evidence that the Chinese did it. But if I am wrong and it does exist, then it surely refers to the real exchange rate, not the nominal rate. Thus the fact that the nominal value of the Chinese yuan was pegged for a period of time has no relevance to whether the currency was being “manipulated”. The real value of the yuan was appreciating.

One cannot conclude that an appreciating yuan means that China was not manipulating its currency. As I pointed out above, and as Corden explains, exchange-rate protection is associated with the accumulation of foreign-exchange reserves by the central bank. There is an ambiguity in interpreting the motivation of the central bank that is accumulating foreign-exchange reserves. Is it accumulating because it wants to increase the amount of reserves in its vaults, or are the increased holdings merely an unwelcome consequence of a policy being pursued for other reasons? In either case, the amount of foreign-exchange reserves a central bank is willing to hold is not unlimited. When the pile of reserves gets high enough, the policy causing accumulation may start to change, implying that the real exchange rate will start to rise.

The dollar was pegged to gold from 1879 to 1933, and yet I don’t think the US government was “manipulating” the exchange rate. And if it was, it was not by fixing the gold price peg, it would have been by depreciating the real value of the dollar via policies that increased national saving, or reduced national investment, in order to run a current account surplus. In my view it is misleading to call policies that promote national saving “currency manipulation”, and even more so to put that label on just a subset of pro-saving policies.

As in the case of the Bank of France after 1928, with a fixed exchange rate, whether a central bank is guilty of currency manipulation depends on whether the initial currency peg was chosen with a view toward creating a competitive advantage for the country’s tradable-goods sector. That was clearly an important motivation when the Bank of France chose the conversion rate between gold and the franc. I haven’t studied the choice of the dollar peg to gold in 1879.

If economists want to use the term ‘currency manipulation’, then they first need to define the term. I have not seen any definitions that make any sense.

I’m hoping that Corden’s definition works for Scott. It does for me.

Cyclical versus Secular Causes of Stagnation

Published March 10, 2017 long-term unemployment , Nick Rowe , Scott Sumner , walter oi 5 Comments

Nick Rowe and Scott Sumner have recently had an interesting little debate about whether the slowdown in real GDP growth and labor productivity since the 2007-09 downturn is the result of cyclical or secular factors. Nick argues that successful inflation targeting in the two decades before the 2007 downturn had given rise to entrepreneurial expectations of stable aggregate demand, thereby providing a supportive macroeconomic environment for long-term investment that generates rising labor productivity over time. By undermining confidence in macroeconomic stability, the 2007-09 downturn diminished the willingness of businesses to continue make long-term investments and thus compromised one of the institutional pillars supporting long-term investment and productivity growth. Despite a recovery, expectations of future aggregate demand are now held with less confidence – higher perceived variance – than previously, thereby reducing entrepreneurial willingness to commit to the long-term capital expansion that increases productivity.

Scott is skeptical of the argument, because productivity growth had already started to decline after the 2001 downturn. Of course, one could argue that geopolitical uncertainty after the 9/11 attack and the invasions of Afghanistan and Iraq could have had a similar depressing effect on investment well before the 2007 downturn. So the decline in productivity growth that was underway at the time of the 2007 downturn is not necessarily inconsistent with Nick’s basic story. But Scott at least partially defends himself against that response by showing that real long-term investment as a share of GDP rose sharply after the 2001 downturn and was well above the levels of 1950s and 1960s.

Seeing no reason why the pace of productivity growth couldn’t have been affected by both cyclical and secular forces, I am happy to agree with both Nick and Scott. But I also have my own theory about the slowdown in productivity growth, which I have discussed previously, so this seems like a good time to weigh in again on the topic. As I pointed out in a 2015 post, one characteristic that distinguishes the 2007-09 downturn from earlier downturns is that it was associated with relatively large sectoral shifts in demand. Thus, the 2007-09 downturn was characterized by a higher percentage of jobs lost in the downturn that were not subsequently restored than was the case in earlier downturns. In earlier downturns, the decline in aggregate demand caused workers to be laid off temporarily from their jobs when demand and output fell, but a large percentage of laid-off workers were later rehired by their former employers when demand and output recovered. And even many of those laid-off workers that weren’t rehired by their previous employers still eventually found jobs doing work very similar to what they had been doing before losing their old jobs.

The depth and the severity of recessions can be measured not just by the unemployment rate, but also by the long-term unemployment rate. What set the 2007-09 downturn and the recovery apart from earlier downturns — even the 1981-82 downturn, in which the unemployment rate rose to almost 11 percent, higher than the 10 percent rate at depth of the 2007-09 downturn – was a long-term unemployment rate substantially higher, followed by a slower rate of decline, than in any post-World-War II downturn. I quote from a recent article on long-term unemployment

In January 2017, there were 1.85 million long-term unemployed. The number first dropped below two million in May 2015. That means 24.2 percent of the unemployed have been looking for work for six months. That’s better than the record high of 46 percent in the second quarter of 2010.

Sadly, it’s barely better than the darkest days of the 1981 recession. At that point, 26 percent of the unemployed were out of work for more than six months. On the other hand, total unemployment was worse than it is today. There was a 10.8 percent overall unemployment rate. In other words, the Great Recession created a higher percent of long-term unemployment.(Source: “Potential Causes and Implications of the Rise in Long-Term Unemployment,” The Federal Reserve Bank of Richmond, September 2011.)

Here’s how I put it in 2015.

[T]he 2008-09 downturn was associated with major sectoral shifts that caused an unusually large reallocation of labor from industries like construction and finance to other industries so that an unusually large number of workers have had to find new jobs doing work different from what they were doing previously. In many recessions, laid-off workers are either re-employed at their old jobs or find new jobs doing basically the same work that they had been doing at their old jobs. When workers transfer from one job to another similar job, there is little reason to expect a decline in their productivity after they are re-employed, but when workers are re-employed doing something very different from what they did before, a significant drop in their productivity in their new jobs is likely.

In addition, the number of long-term unemployed (27 weeks or more) since the 2000-09 downturn has been unusually high. Workers who remain unemployed for an extended period of time tend to suffer an erosion of skills, causing their productivity to drop when they are re-employed even if they are able to find a new job in their old occupation. It seems likely that the percentage of long-term unemployed workers that switch occupations is larger than the percentage of short-term unemployed workers that switch occupations, so the unusually high rate of long-term unemployment has probably had a doubly negative effect on labor productivity.

Long-term unemployment has adverse effects on health and many other metrics of well-being, effects that aren’t confined to the unemployed, but extend to their families, friends and communities. An increase in long-term unemployment, even if originally caused by an aggregate demand shock, is associated with a long-term negative supply shock. So it’s not surprising that the unusually and persistently high rate of long-term unemployment after the 2007-09 downturn, causing a massive loss of human capital, has depressed the subsequent growth in labor productivity. In my 2015 post, I tried to provide an optimistic interpretation of this phenomenon, but my optimism was misplaced, because the damage inflicted by long-term unemployment is very often irreversible, and rates of long-term unemployment have remained stubbornly high notwithstanding the steady decline in the overall unemployment rate.

Accounting for a disproportionate share of the long-term unemployed, discouraged older workers, chronically unable to find new jobs, have prematurely departed from the labor force. These older workers have presumably been replaced by younger entrants into the labor force, and one would suppose that the productivity of the younger workers is, on average, substantially lower than the productivity of the older and more experienced workers whom they have replaced, though presumably as they gain experience and acquire skills, the productivity of new workers will rise over time. Thus the demographic shift in the labor force is another reason for the low productivity growth since the 2007-09 downturn. But that effect, though largely demographic, has also had a cyclical component, making it difficult to disentangle the cyclical from the secular causes of sluggish productivity growth.

That difficulty is further compounded by another contributory cause of slow productivity growth. In my 2016 post, I discussed the late Walter Oi’s idea that labor is not really a variable factor of production as it is typically treated in simplified models, but a quasi-fixed factor. Here’s how Oi explained the idea:

For analytic purposes fixed employment costs can be separated into two categories called, for convenience, hiring and training costs. Hiring costs are defined as those costs that have no effect on a worker’s productivity and include outlays for recruiting, for processing payroll records, and for supplements such as unemployment compensation. These costs are closely related to the number of new workers and only indirectly related to the flow of labor’s services Training expenses, on the other hand, are investments in the human agent, specifically designed to improve a worker’s productivity.

The training activity typically entails direct money outlays as well as numerous implicit costs such as the allocation of old workers to teaching skills and rejection of unqualified workers during the training period.

So, if the 2007-09 downturn and the recovery was associated with an unusually high flow of workers from old jobs into new jobs, there has been an unusually high level of training expenses incurred by firms as they have brought workers into new jobs. The large investments by firms in training new workers have inevitably caused measured labor productivity to lag below previous trends when the fraction of workers entering the labor force or requiring new training to learn new skills was likely less than it has been since 2009. This idea, at any rate, does provide some reason to hope for at least a modest improvement in productivity and economic growth over time, even if the human cost of almost a decade of extremely high long-term unemployment is now largely irremediable and irretrievable.

Yes, Judges Do Make Law

Published February 5, 2017 Neil Gorsuch , Ronald Dworkin , Scott Sumner , Uncategorized 14 Comments

Scott Sumner has just written an interesting comment to my previous post in which I criticized a remark made by Judge Gorsuch upon being nominated to fill the vacant seat on the Supreme Court — so interesting, in fact, that I think it is worth responding to him in a separate post.

First, here is the remark made by Judge Gorsuch to which I took exception.

I respect, too, the fact that in our legal order, it is for Congress and not the courts to write new laws. It is the role of judges to apply, not alter, the work of the people’s representatives. A judge who likes every outcome he reaches is very likely a bad judge . . . stretching for results he prefers rather than those the law demands.

I criticized Judge Gorsuch for denying what to me is the obvious fact that judges do make law. They make law, because the incremental effect of each individual decision results in a legal order that is different from the legislation that has been enacted by legislatures. Each decision creates a precedent that must be considered by other judges as they apply and construe the sum total of legislatively enacted statutes in light of, and informed by, the precedents of judges and the legal principles that have guided judges those precedents. Law-making by judges under a common law system — even a common law system in which judges are bound to acknowledge the authority of statutory law — is inevitable for many reasons, one but not the only reason being that statutes will sooner or later have to be applied in circumstances were not foreseen by that legislators who enacted those statutes.

To take an example of Constitutional law off the top of my head: is it an unreasonable search for the police to search the cell phone of someone they have arrested without first getting a search warrant? That’s what the Supreme Court had to decide two years ago in Riley v. California. The answer to that question could not be determined by reading the text of the Fourth Amendment which talks about the people being secure in their “persons, houses, papers, or effects” or doing a historical analysis of what the original understanding of the terms “search” and “seizure” and “papers and effects” was when the Fourth Amendment to the Constitution was enacted. Earlier courts had to decide whether government eavesdropping on phone calls violated the Fourth Amendment. And other courts have had to decide whether collecting meta data about phone calls is a violation. Answers to those legal questions can’t be found by reading the relevant legal text.

Here’s part of the New York Times story about the Supreme Court’s decision in Riley v. Califronia.

In a sweeping victory for privacy rights in the digital age, the Supreme Court on Wednesday unanimously ruled that the police need warrants to search the cellphones of people they arrest.

While the decision will offer protection to the 12 million people arrested every year, many for minor crimes, its impact will most likely be much broader. The ruling almost certainly also applies to searches of tablet and laptop computers, and its reasoning may apply to searches of homes and businesses and of information held by third parties like phone companies.

“This is a bold opinion,” said Orin S. Kerr, a law professor at George Washington University. “It is the first computer-search case, and it says we are in a new digital age. You can’t apply the old rules anymore.”

But he added that old principles required that their contents be protected from routine searches. One of the driving forces behind the American Revolution, Chief Justice Roberts wrote, was revulsion against “general warrants,” which “allowed British officers to rummage through homes in an unrestrained search for evidence of criminal activity.”

“The fact that technology now allows an individual to carry such information in his hand,” the chief justice also wrote, “does not make the information any less worthy of the protection for which the founders fought.”

Now for Scott’s comment:

I don’t see how Gorsuch’s view conflicts with your view. It seems like Gorsuch is saying something like “Judges should not legislate, they should interpret the laws.” And you are saying “the laws are complicated.” Both can be true!

Well, in a sense, maybe, because what judges do is technically not legislation. But they do make law; their opinions determine for the rest of us what we may legally do and what we may not legally do and what rights to expect will be respected  and what rights will not be respected. Judges can even change the plain meaning of a statute in order to uphold a more basic, if unwritten, principle of justice, which,under, the plain meaning of Judge Gorsuch’s remark (“It is the role of judges to apply, not alter, the work of the people’s representatives”) would have to be regarded as an abuse of judicial discretion. The absurdity of what I take to be Gorsuch’s position is beautifully illustrated by the case of Riggs v. Palmer which the late — and truly great — Ronald Dworkin discussed in his magnificent article “Is Law a System of Rules?” aka “The Model of Rules.” Here is the one paragraph in which Dworkin uses the Riggs case to show that judges apply not just specific legal rules (e.g., statutory rules), but also deeper principles that govern how those rules should be applied.

My immediate purpose, however, is to distinguish principles in the generic sense from rules, and I shall start by collecting some examples of the former. The examples I offer are chosen haphazardly; almost any case in a law school casebook would provide examples that would serve as well. In 1889, a New York court, in the famous case of Riggs v. Palmer, had to decide whether an heir named in the will of his grandfather could inherit under that will, even though he had murdered his grandfather to do so. The court began its reasoning with this admission: “It is quite true that statues regulating the making, proof and effect of wills, and the devolution of property, if literally construed [my emphasis], and if their force and effect can in no way and under no circumstances be controlled or modified, give this property to the murderer.” But the court continued to note that “all laws as well as all contracts may be controlled in their operation and effect by general, fundamental maxims of the common law. No one shall be permitted to profit by his own fraud, or to take advantage of his own wrong, or to found any claim upon his own iniquity, or to acquire property by his own crime.” The murderer did not receive his inheritance.

QED. In this case the Common law overruled the statute, and justice prevailed over injustice. Game, set, match to the judge!

Making Sense of Rational Expectations

Published November 29, 2016 John Muth , rational expectations , Robert Shiller , Scott Sumner , Thomas Schelling 26 Comments

Almost two months ago I wrote a provocatively titled post about rational expectations, in which I argued against the idea that it is useful to make the rational-expectations assumption in developing a theory of business cycles. The title of the post was probably what led to the start of a thread about my post on the econjobrumors blog, the tenor of which  can be divined from the contribution of one commenter: “Who on earth is Glasner?” But, aside from the attention I received on econjobrumors, I also elicited a response from Scott Sumner

David Glasner has a post criticizing the rational expectations modeling assumption in economics:

What this means is that expectations can be rational only when everyone has identical expectations. If people have divergent expectations, then the expectations of at least some people will necessarily be disappointed — the expectations of both people with differing expectations cannot be simultaneously realized — and those individuals whose expectations have been disappointed will have to revise their plans. But that means that the expectations of those people who were correct were also not rational, because the prices that they expected were not equilibrium prices. So unless all agents have the same expectations about the future, the expectations of no one are rational. Rational expectations are a fixed point, and that fixed point cannot be attained unless everyone shares those expectations.

Beyond that little problem, Mason raises the further problem that, in a rational-expectations equilibrium, it makes no sense to speak of a shock, because the only possible meaning of “shock” in the context of a full intertemporal (aka rational-expectations) equilibrium is a failure of expectations to be realized. But if expectations are not realized, expectations were not rational.

I see two mistakes here. Not everyone must have identical expectations in a world of rational expectations. Now it’s true that there are ratex models where people are simply assumed to have identical expectations, such as representative agent models, but that modeling assumption has nothing to do with rational expectations, per se.

In fact, the rational expectations hypothesis suggests that people form optimal forecasts based on all publicly available information. One of the most famous rational expectations models was Robert Lucas’s model of monetary misperceptions, where people observed local conditions before national data was available. In that model, each agent sees different local prices, and thus forms different expectations about aggregate demand at the national level.

It is true that not all expectations must be identical in a world of rational expectations. The question is whether those expectations are compatible with the equilibrium of the model in which those expectations are embedded. If any of those expectations are incompatible with the equilibrium of the model, then, if agents’ decision are based on their expectations, the model will not arrive at an equilibrium solution. Lucas’s monetary misperception model was a clever effort to tweak the rational-expectations assumption just enough to allow for a temporary disequilibrium. But the attempt was a failure, because Lucas could only generate a one-period deviation from equilibrium, which was too little for the model to pose as a plausible account of a business cycle. That provided Kydland and Prescott the idea to discard Lucas’s monetary misperceptions idea and write their paper on real business cycles without adulterating the rational expectations assumption.

Here’s what Muth said about the rational expectations assumption in the paper in which he introduced “rational expectations” as a modeling strategy.

In order to explain these phenomena, I should like to suggest that expectations, since they are informed predictions of future events, are essentially the same as the predictions of the relevant economic theory. At the risk of confusing this purely descriptive hypothesis with a pronouncement as to what firms ought to do, we call such expectations “rational.”

The hypothesis can be rephrased a little more precisely as follows: that expectations of firms (or, more generally, the subjective probability distribution of outcomes) tend to be distributed, for the same information set, about the prediction of the theory (or the “objective” probability distributions of outcomes).

The hypothesis asserts three things: (1) Information is scarce, and the economic system generally does not waste it. (2) The way expectations are formed depends specifically on the structure of the relevant system describing the economy. (3) A “public prediction,” in the sense of Grunberg and Modigliani, will have no substantial effect on the operation of the economic system (unless it is based on inside information).

It does not assert that the scratch work of entrepreneurs resembles the system of equations in any way; nor does it state that predictions of entrepreneurs are perfect or that their expectations are all the same. For purposes of analysis, we shall use a specialized form of the hypothesis. In particular, we assume: 1. The random disturbances are normally distributed. 2. Certainty equivalents exist for the variables to be predicted. 3. The equations of the system, including the expectations formulas, are linear. These assumptions are not quite so strong as may appear at first because any one of them virtually implies the other two.

It seems to me that Muth was confused about what the rational-expectations assumption entails. He asserts that the expectations of entrepreneurs — and presumably that applies to other economic agents as well insofar as their decisions are influenced by their expectations of the future – should be assumed to be exactly what the relevant economic model predicts the expected outcomes to be. If so, I don’t see how it can be maintained that expectations could diverge from each other. If what entrepreneurs produce next period depends on the price they expect next period, then how is it possible that the total supply produced next period is independent of the distribution of expectations as long as the errors are normally distributed and the mean of the distribution corresponds to the equilibrium of the model? This could only be true if the output produced by each entrepreneur was a linear function of the expected price and all entrepreneurs had identical marginal costs or if the distribution of marginal costs was uncorrelated with the distribution of expectations. The linearity assumption is hardly compelling unless you assume that the system is in equilibrium and all changes are small. But making that assumption is just another form of question begging.

It’s also wrong to say:

But if expectations are not realized, expectations were not rational.

Scott is right. What I said was wrong. What I ought to have said is: “But if expectations (being divergent) could not have been realized, those expectations were not rational.”

Suppose I am watching the game of roulette. I form the expectation that the ball will not land on one of the two green squares. Now suppose it does. Was my expectation rational? I’d say yes—there was only a 2/38 chance of the ball landing on a green square. It’s true that I lacked perfect foresight, but my expectation was rational, given what I knew at the time.

I don’t think that Scott’s response is compelling, because you can’t judge the rationality of an expectation in isolation, it has to be judged in a broader context. If you are forming your expectation about where the ball will fall in a game of roulette, the rationality of that expectation can only be evaluated in the context of how much you should be willing to bet that the ball will fall on one of the two green squares and that requires knowledge of what the payoff would be if the ball did fall on one of those two squares. And that would mean that someone else is involved in the game and would be taking an opposite position. The rationality of expectations could only be judged in the context of what everyone participating in the game was expecting and what the payoffs and penalties were for each participant.

In 2006, it might have been rational to forecast that housing prices would not crash. If you lived in many countries, your forecast would have been correct. If you happened to live in Ireland or the US, your forecast would have been incorrect. But it might well have been a rational forecast in all countries.

The rationality of a forecast can’t be assessed in isolation. A forecast is rational if it is consistent with other forecasts, so that it, along with the other forecasts, could potentially be realized. As a commenter on Scott’s blog observed, a rational expectation is an expectation that, at the time the forecast is made, is consistent with the relevant model. The forecast of housing prices may turn out to be incorrect, but the forecast might still have been rational when it was made if the forecast of prices was consistent with what the relevant model would have predicted. The failure of the forecast to be realized could mean either that forecast was not consistent with the model, or that between the time of the forecast and the time of its realization, new information,  not available at the time of the forecast, came to light and changed the the prediction of the relevant model.

The need for context in assessing the rationality of expectations was wonderfully described by Thomas Schelling in his classic analysis of cooperative games.

One may or may not agree with any particular hypothesis as to how a bargainer’s expectations are formed either in the bargaining process or before it and either by the bargaining itself or by other forces. But it does seem clear that the outcome of a bargaining process is to be described most immediately, most straightforwardly, and most empirically, in terms of some phenomenon of stable and convergent expectations. Whether one agrees explicitly to a bargain, or agrees tacitly, or accepts by default, he must if he has his wits about him, expect that he could do no better and recognize that the other party must reciprocate the feeling. Thus, the fact of an outcome, which is simply a coordinated choice, should be analytically characterized by the notion of convergent expectations.

The intuitive formulation, or even a careful formulation in psychological terms, of what it is that a rational player expects in relation to another rational player in the “pure” bargaining game, poses a problem in sheer scientific description. Both players, being rational, must recognize that the only kind of “rational” expectation they can have is a fully shared expectation of an outcome. It is not quite accurate – as a description of a psychological phenomenon – to say that one expects the second to concede something; the second’s readiness to concede or to accept is only an expression of what he expects the first to accept or to concede, which in turn is what he expects the first to expect the second to expect the first to expect, and so on. To avoid an “ad infinitum” in the description process, we have to say that both sense a shared expectation of an outcome; one’s expectation is a belief that both identify the outcome as being indicated by the situation, hence as virtually inevitable. Both players, in effect, accept a common authority – the power of the game to dictate its own solution through their intellectual capacity to perceive it – and what they “expect” is that they both perceive the same solution.

Viewed in this way, the intellectual process of arriving at “rational expectations” in the full-communication “pure” bargaining game is virtually identical with the intellectual process of arriving at a coordinated choice in the tacit game. The actual solutions might be different because the game contexts might be different, with different suggestive details; but the intellectual nature of the two solutions seems virtually identical since both depend on an agreement that is reached by tacit consent. This is true because the explicit agreement that is reached in the full communication game corresponds to the a prioir expectations that were reached (or in theory could have been reached) jointly but independently by the two players before the bargaining started. And it is a tacit “agreement” in the sense that both can hold confident rational expectation only if both are aware that both accept the indicated solution in advance as the outcome that they both know they both expect.

So I agree that rational expectations can simply mean that agents are forming expectations about the future incorporating as best as they can all the knowledge available to them. This is a weak common sense interpretation of rational expectations that I think is what Scott Sumner has in mind when he uses the term “rational expectations.” But in the context of formal modelling, rational expectations has a more restrictive meaning, which is that given all the information available, the expectations of all agents in the model must correspond to what the model itself predicts given that information. Even though Muth himself and others have tried to avoid the inference that all agents must have expectations that match the solution of the model, given the information underlying the model, the assumptions under which agents could hold divergent expectations are, in their own way, just as restrictive as the assumption that agents hold convergent expectations.

In a way, the disconnect between a common-sense understanding of what “rational expectations” means and what “rational expectations” means in the context of formal macroeconomic models is analogous to the disconnect between what “competition” means in normal discourse and what “competition” (and especially “perfect competition”) means in the context of formal microeconomic models. Much of the rivalrous behavior between competitors that we think of as being essential aspects of competition and the competitive process is simply ruled out by the formal assumption of perfect competition.

What’s Wrong with EMH?

Published July 19, 2016 Efficient Market Hypothesis , expectations , Paul Krugman , rational expectations , Scott Sumner , Uncategorized 16 Comments

Scott Sumner wrote a post commenting on my previous post about Paul Krugman’s column in the New York Times last Friday. I found Krugman’s column really interesting in his ability to pack so much real economic content into an 800-word column written to help non-economists understand recent fluctuations in the stock market. Part of what I was doing in my post was to offer my own criticism of the efficient market hypothesis (EMH) of which Krugman is probably not an enthusiastic adherent either. Nevertheless, both Krugman and I recognize that EMH serves as a useful way to discipline how we think about fluctuating stock prices.

Here is a passage of Krugman’s that I commented on:

But why are long-term interest rates so low? As I argued in my last column, the answer is basically weakness in investment spending, despite low short-term interest rates, which suggests that those rates will have to stay low for a long time.

My comment was:

Again, this seems inexactly worded. Weakness in investment spending is a symptom not a cause, so we are back to where we started from. At the margin, there are no attractive investment opportunities.

Scott had this to say about my comment:

David is certainly right that Krugman’s statement is “inexactly worded”, but I’m also a bit confused by his criticism. Certainly “weakness in investment spending” is not a “symptom” of low interest rates, which is how his comment reads in context.  Rather I think David meant that the shift in the investment schedule is a symptom of a low level of AD, which is a very reasonable argument, and one he develops later in the post.  But that’s just a quibble about wording.  More substantively, I’m persuaded by Krugman’s argument that weak investment is about more than just AD; the modern information economy (with, I would add, a slowgrowing working age population) just doesn’t generate as much investment spending as before, even at full employment.

Just to be clear, what I was trying to say was that investment spending is determined by “fundamentals,” i.e., expectations about future conditions (including what demand for firms’ output will be, what competing firms are planning to do, what cost conditions will be, and a whole range of other considerations. It is the combination of all those real and psychological factors that determines the projected returns from undertaking an investment, and those expected returns must be compared with the cost of capital to reach a final decision about which projects will be undertaken, thereby giving rise to actual investment spending. So I certainly did not mean to say that weakness in investment spending is a symptom of low interest rates. I meant that it is a symptom of the entire economic environment that, depending on the level of interest rates, makes specific investment projects seem attractive or unattractive. Actually, I don’t think that there is any real disagreement between Scott and me on this particular point; I just mention the point to avoid possible misunderstandings.

But the differences between Scott and me about the EMH seem to be substantive. Scott quotes this passage from my previous post:

The efficient market hypothesis (EMH) is at best misleading in positing that market prices are determined by solid fundamentals. What does it mean for fundamentals to be solid? It means that the fundamentals remain what they are independent of what people think they are. But if fundamentals themselves depend on opinions, the idea that values are determined by fundamentals is a snare and a delusion.

Scott responded as follows:

I don’t think it’s correct to say the EMH is based on “solid fundamentals”.  Rather, AFAIK, the EMH says that asset prices are based on rational expectations of future fundamentals, what David calls “opinions”.  Thus when David tries to replace the EMH view of fundamentals with something more reasonable, he ends up with the actual EMH, as envisioned by people like Eugene Fama.  Or am I missing something?

In fairness, David also rejects rational expectations, so he would not accept even my version of the EMH, but I think he’s too quick to dismiss the EMH as being obviously wrong. Lots of people who are much smarter than me believe in the EMH, and if there was an obvious flaw I think it would have been discovered by now.

I accept Scott’s correction that EMH is based on the rational expectation of future fundamentals, but I don’t think that the distinction is as meaningful as Scott does. The problem is that in a typical rational-expectations model, the fundamentals are given and don’t change, so that fundamentals are actually static. The seemingly non-static property of a rational-expectations model is achieved by introducing stochastic parameters with known means and variances, so that the ultimate realizations of stochastic variables within the model are not known in advance. However, the rational expectations of all stochastic variables are unbiased, and they are – in some sense — the best expectations possible given the underlying stochastic nature of the variables. But given that stochastic structure, current asset prices reflect the actual – and unchanging — fundamentals, the stochastic elements in the model being fully reflected in asset prices today. Prices may change ex post, but, conditional on the realizations of the stochastic variables (whose probability distributions are assumed to have been known in advance), those changes are fully anticipated. Thus, in a rational-expectations equilibrium, causation still runs from fundamentals to expectations.

The problem with rational expectations is not a flaw in logic. In fact, the importance of rational expectations is that it is a very important logical test for the coherence of a model. If a model cannot be solved for a rational-expectations equilibrium, it suffers from a basic lack of coherence. Something is basically wrong with a model in which the expectation of the equilibrium values predicted by the model does not lead to their realization. But a logical property of the model is not the same as a positive theory of how expectations are formed and how they evolve. In the real world, knowledge is constantly growing, and new knowledge implies that the fundamentals underlying the economy must be changing as knowledge grows. The future fundamentals that will determine the future prices of a future economy cannot be rationally expected in the present, because we have no way of specifying probability distributions corresponding to dynamic evolving systems.

If future fundamentals are logically unknowable — even in a probabilistic sense — in the present, because we can’t predict what our future knowledge will be, because if we could, future knowledge would already be known, making it present knowledge, then expectations of the future can’t possibly be rational because we never have the knowledge that would be necessary to form rational expectations. And so I can’t accept Scott’s assertion that asset prices are based on rational expectations of future fundamentals. It seems to me that the causation goes in the other direction as well: future fundamentals will be based, at least in part, on current expectations.

About Me

David Glasner
Washington, DC

I am an economist in the Washington DC area. My research and writing has been mostly on monetary economics and policy and the history of economics. In my book Free Banking and Monetary Reform, I argued for a non-Monetarist non-Keynesian approach to monetary policy, based on a theory of a competitive supply of money. Over the years, I have become increasingly impressed by the similarities between my approach and that of R. G. Hawtrey and hope to bring Hawtrey’s unduly neglected contributions to the attention of a wider audience.

My new book Studies in the History of Monetary Theory: Controversies and Clarifications has been published by Palgrave Macmillan

Follow me on Twitter @david_glasner

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