Archive for the 'expectations' Category

Neo-Fisherism and All That

A few weeks ago Michael Woodford and his Columbia colleague Mariana Garcia-Schmidt made an initial response to the Neo-Fisherian argument advanced by, among others, John Cochrane and Stephen Williamson that a central bank can achieve its inflation target by pegging its interest-rate instrument at a rate such that if the expected inflation rate is the inflation rate targeted by the central bank, the Fisher equation would be satisfied. In other words, if the central bank wants 2% inflation, it should set the interest rate instrument under its control at the Fisherian real rate of interest (aka the natural rate) plus 2% expected inflation. So if the Fisherian real rate is 2%, the central bank should set its interest-rate instrument (Fed Funds rate) at 4%, because, in equilibrium – and, under rational expectations, that is the only policy-relevant solution of the model – inflation expectations must satisfy the Fisher equation.

The Neo-Fisherians believe that, by way of this insight, they have overturned at least two centuries of standard monetary theory, dating back at least to Henry Thornton, instructing the monetary authorities to raise interest rates to combat inflation and to reduce interest rates to counter deflation. According to the Neo-Fisherian Revolution, this was all wrong: the way to reduce inflation is for the monetary authority to reduce the setting on its interest-rate instrument and the way to counter deflation is to raise the setting on the instrument. That is supposedly why the Fed, by reducing its Fed Funds target practically to zero, has locked us into a low-inflation environment.

Unwilling to junk more than 200 years of received doctrine on the basis, not of a behavioral relationship, but a reduced-form equilibrium condition containing no information about the direction of causality, few monetary economists and no policy makers have become devotees of the Neo-Fisherian Revolution. Nevertheless, the Neo-Fisherian argument has drawn enough attention to elicit a response from Michael Woodford, who is the go-to monetary theorist for monetary-policy makers. The Woodford-Garcia-Schmidt (hereinafter WGS) response (for now just a slide presentation) has already been discussed by Noah Smith, Nick Rowe, Scott Sumner, Brad DeLong, Roger Farmer and John Cochrane. Nick Rowe’s discussion, not surprisingly, is especially penetrating in distilling the WGS presentation into its intuitive essence.

Using Nick’s discussion as a starting point, I am going to offer some comments of my own on Neo-Fisherism and the WGS critique. Right off the bat, WGS concede that it is possible that by increasing the setting of its interest-rate instrument, a central bank could, move the economy from one rational-expectations equilibrium to another, the only difference between the two being that inflation in the second would differ from inflation in the first by an amount exactly equal to the difference in the corresponding settings of the interest-rate instrument. John Cochrane apparently feels pretty good about having extracted this concession from WGS, remarking

My first reaction is relief — if Woodford says it is a prediction of the standard perfect foresight / rational expectations version, that means I didn’t screw up somewhere. And if one has to resort to learning and non-rational expectations to get rid of a result, the battle is half won.

And my first reaction to Cochrane’s first reaction is: why only half? What else is there to worry about besides a comparison of rational-expectations equilibria? Well, let Cochrane read Nick Rowe’s blogpost. If he did, he might realize that if you do no more than compare alternative steady-state equilibria, ignoring the path leading from one equilibrium to the other, you miss just about everything that makes macroeconomics worth studying (by the way I do realize the question-begging nature of that remark). Of course that won’t necessarily bother Cochrane, because, like other practitioners of modern macroeconomics, he has convinced himself that it is precisely by excluding everything but rational-expectations equilibria from consideration that modern macroeconomics has made what its practitioners like to think of as progress, and what its critics regard as the opposite .

But Nick Rowe actually takes the trouble to show what might happen if you try to specify the path by which you could get from rational-expectations equilibrium A with the interest-rate instrument of the central bank set at i to rational-expectations equilibrium B with the interest-rate instrument of the central bank set at i ­+ ε. If you try to specify a process of trial-and-error (tatonnement) that leads from A to B, you will almost certainly fail, your only chance being to get it right on your first try. And, as Nick further points out, the very notion of a tatonnement process leading from one equilibrium to another is a huge stretch, because, in the real world there are “no backs” as there are in tatonnement. If you enter into an exchange, you can’t nullify it, as is the case under tatonnement, just because the price you agreed on turns out not to have been an equilibrium price. For there to be a tatonnement path from the first equilibrium that converges on the second requires that monetary authority set its interest-rate instrument in the conventional, not the Neo-Fisherian, manner, using variations in the real interest rate as a lever by which to nudge the economy onto a path leading to a new equilibrium rather than away from it.

The very notion that you don’t have to worry about the path by which you get from one equilibrium to another is so bizarre that it would be merely laughable if it were not so dangerous. Kenneth Boulding used to tell a story about a physicist, a chemist and an economist stranded on a desert island with nothing to eat except a can of food, but nothing to open the can with. The physicist and the chemist tried to figure out a way to open the can, but the economist just said: “assume a can opener.” But I wonder if even Boulding could have imagined the disconnect from reality embodied in the Neo-Fisherian argument.

Having registered my disapproval of Neo-Fisherism, let me now reverse field and make some critical comments about the current state of non-Neo-Fisherian monetary theory, and what makes it vulnerable to off-the-wall ideas like Neo-Fisherism. The important fact to consider about the past two centuries of monetary theory that I referred to above is that for at least three-quarters of that time there was a basic default assumption that the value of money was ultimately governed by the value of some real commodity, usually either silver or gold (or even both). There could be temporary deviations between the value of money and the value of the monetary standard, but because there was a standard, the value of gold or silver provided a benchmark against which the value of money could always be reckoned. I am not saying that this was either a good way of thinking about the value of money or a bad way; I am just pointing out that this was metatheoretical background governing how people thought about money.

Even after the final collapse of the gold standard in the mid-1930s, there was a residue of metalism that remained, people still calculating values in terms of gold equivalents and the value of currency in terms of its gold price. Once the gold standard collapsed, it was inevitable that these inherited habits of thinking about money would eventually give way to new ways of thinking, and it took another 40 years or so, until the official way of thinking about the value of money finally eliminated any vestige of the gold mentality. In our age of enlightenment, no sane person any longer thinks about the value of money in terms of gold or silver equivalents.

But the problem for monetary theory is that, without a real-value equivalent to assign to money, the value of money in our macroeconomic models became theoretically indeterminate. If the value of money is theoretically indeterminate, so, too, is the rate of inflation. The value of money and the rate of inflation are simply, as Fischer Black understood, whatever people in the aggregate expect them to be. Nevertheless, our basic mental processes for understanding how central banks can use an interest-rate instrument to control the value of money are carryovers from an earlier epoch when the value of money was determined, most of the time and in most places, by convertibility, either actual or expected, into gold or silver. The interest-rate instrument of central banks was not primarily designed as a method for controlling the value of money; it was the mechanism by which the central bank could control the amount of reserves on its balance sheet and the amount of gold or silver in its vaults. There was only an indirect connection – at least until the 1920s — between a central bank setting its interest-rate instrument to control its balance sheet and the effect on prices and inflation. The rules of monetary policy developed under a gold standard are not necessarily applicable to an economic system in which the value of money is fundamentally indeterminate.

Viewed from this perspective, the Neo-Fisherian Revolution appears as a kind of reductio ad absurdum of the present confused state of monetary theory in which the price level and the rate of inflation are entirely subjective and determined totally by expectations.

A New Paper on the Short, But Sweet, 1933 Recovery Confirms that Hawtrey and Cassel Got it Right

In a recent post, the indispensable Marcus Nunes drew my attention to a working paper by Andrew Jalil of Occidental College and Gisela Rua of the Federal Reserve Board. The paper is called “Inflation Expectations and Recovery from the Depression in 1933: Evidence from the Narrative Record. “ Subsequently I noticed that Mark Thoma had also posted the abstract on his blog.

 Here’s the abstract:

This paper uses the historical narrative record to determine whether inflation expectations shifted during the second quarter of 1933, precisely as the recovery from the Great Depression took hold. First, by examining the historical news record and the forecasts of contemporary business analysts, we show that inflation expectations increased dramatically. Second, using an event-studies approach, we identify the impact on financial markets of the key events that shifted inflation expectations. Third, we gather new evidence—both quantitative and narrative—that indicates that the shift in inflation expectations played a causal role in stimulating the recovery.

There’s a lot of new and interesting stuff in this paper even though the basic narrative framework goes back almost 80 years to the discussion of the 1933 recovery in Hawtrey’s Trade Depression and The Way Out. The paper highlights the importance of rising inflation (or price-level) expectations in generating the recovery, which started within a few weeks of FDR’s inauguration in March 1933. In the absence of direct measures of inflation expectations, such as breakeven TIPS spreads, that are now available, or surveys of consumer and business expectations, Jalil and Rua document the sudden and sharp shift in expectations in three different ways.

First, they show document that there was a sharp spike in news coverage of inflation in April 1933. Second, they show an expectational shift toward inflation by a close analysis of the economic reporting and commentary in the Economist and in Business Week, providing a fascinating account of the evolution of FDR’s thinking and how his economic policy was assessed in the period between the election in November 1932 and April 1933 when the gold standard was suspended. Just before the election, the Economist observed

No well-informed man in Wall Street expects the outcome of the election to make much real difference in business prospects, the argument being that while politicians may do something to bring on a trade slump, they can do nothing to change a depression into prosperity (October 29, 1932)

 On April 22, 1933, just after FDR took the US of the gold standard, the Economist commented

As usual, Wall Street has interpreted the policy of the Washington Administration with uncanny accuracy. For a week or so before President Roosevelt announced his abandonment of the gold standard, Wall Street was “talking inflation.”

 A third indication of increasing inflation is drawn from the five independent economic forecasters which all began predicting inflation — some sooner than others  — during the April-May time frame.

Jalil and Rua extend the important work of Daniel Nelson whose 1991 paper “Was the Deflation of 1929-30 Anticipated? The Monetary Regime as Viewed by the Business Press” showed that the 1929-30 downturn coincided with a sharp drop in price level expectations, providing powerful support for the Hawtrey-Cassel interpretation of the onset of the Great Depression.

Besides persuasive evidence from multiple sources that inflation expectations shifted in the spring of 1933, Jalil and Rua identify 5 key events or news shocks that focused attention on a changing policy environment that would lead to rising prices.

1 Abandonment of the Gold Standard and a Pledge by FDR to Raise Prices (April 19)

2 Passage of the Thomas Inflation Amendment to the Farm Relief Bill by the Senate (April 28)

3 Announcement of Open Market Operations (May 24)

4 Announcement that the Gold Clause Would Be Repealed and a Reduction in the New York Fed’s Rediscount Rate (May 26)

5 FDR’s Message to the World Economic Conference Calling for Restoration of the 1926 Price Level (June 19)

Jalil and Rua perform an event study and find that stock prices rose significantly and the dollar depreciated against gold and pound sterling after each of these news shocks. They also discuss the macreconomic effects of shift in inflation expectations, showing that a standard macro model cannot account for the rapid 1933 recovery. Further, they scrutinize the claim by Friedman and Schwartz in their Monetary History of the United States that, based on the lack of evidence of any substantial increase in the quantity of money, “the economic recovery in the half-year after the panic owed nothing to monetary expansion.” Friedman and Schwartz note that, given the increase in prices and the more rapid increase in output, the velocity of circulation must have increased, without mentioning the role of rising inflation expectations in reducing that amount of cash (relative to income) that people wanted to hold.

Jalil and Rua also offer a very insightful explanation for the remarkably rapid recovery in the April-July period, suggesting that the commitment to raise prices back to their 1926 levels encouraged businesses to hasten their responses to the prospect of rising prices, because prices would stop rising after they reached their target level.

The literature on price-level targeting has shown that, relative to inflation targeting, this policy choice has the advantage of removing more uncertainty in terms of the future level of prices. Under price-level targeting, inflation depends on the relationship between the current price level and its target. Inflation expectations will be higher the lower is the current price level. Thus, Roosevelt’s commitment to a price-level target caused market participants to expect inflation until prices were back at that higher set target.

A few further comments before closing. Jalil and Rua have a brief discussion of whether other factors besides increasing inflation expectations could account for the rapid recovery. The only factor that they mention as an alternative is exit from the gold standard. This discussion is somewhat puzzling inasmuch as they already noted that exit from the gold standard was one of five news shocks (and by all odds the important one) in causing the increase in inflation expectations. They go on to point out that no other country that left the gold standard during the Great Depression experienced anywhere near as rapid a recovery as did the US. Because international trade accounted for a relatively small share of the US economy, they argue that the stimulus to production by US producers of tradable goods from a depreciating dollar would not have been all that great. But that just shows that the macroeconomic significance of abandoning the gold standard was not in shifting the real exchange rate, but in raising the price level. The fact that the US recovery after leaving the gold standard was so much more powerful than it was in other countries is because, at least for a short time, the US sought to use monetary policy aggressively to raise prices, while other countries were content merely to stop the deflation that the gold standard had inflicted on them, but made no attempt to reverse the deflation that had already occurred.

Jalil and Rua conclude with a discussion of possible explanations for why the April-July recovery seemed to peter out suddenly at the end of July. They offer two possible explanations. First passage of the National Industrial Recovery Act in July was a negative supply shock, and second the rapid recovery between April and July persuaded FDR that further inflation was no longer necessary, with actual inflation and expected inflation both subsiding as a result. These are obviously not competing explanations. Indeed the NIRA may have itself been another reason why FDR no longer felt inflation was necessary, as indicated by this news story in the New York Times

The government does not contemplate entering upon inflation of the currency at present and will issue cheaper money only as a last resort to stimulate trade, according to a close adviser of the President who discussed financial policies with him this week. This official asserted today that the President was well satisfied with the business improvement and the government’s ability to borrow money at cheap rates. These are interpreted as good signs, and if the conditions continue as the recovery program broadened, it was believed no real inflation of the currency would be necessary. (“Inflation Putt Off, Officials Suggest,” New York Times, August 4, 1933)

If only . . .

Roger and Me

Last week Roger Farmer wrote a post elaborating on a comment that he had left to my post on Price Stickiness and Macroeconomics. Roger’s comment is aimed at this passage from my post:

[A]lthough price stickiness is a sufficient condition for inefficient macroeconomic fluctuations, it is not a necessary condition. It is entirely possible that even with highly flexible prices, there would still be inefficient macroeconomic fluctuations. And the reason why price flexibility, by itself, is no guarantee against macroeconomic contractions is that macroeconomic contractions are caused by disequilibrium prices, and disequilibrium prices can prevail regardless of how flexible prices are.

Here’s Roger’s comment:

I have a somewhat different take. I like Lucas’ insistence on equilibrium at every point in time as long as we recognize two facts. 1. There is a continuum of equilibria, both dynamic and steady state and 2. Almost all of them are Pareto suboptimal.

I made the following reply to Roger’s comment:

Roger, I think equilibrium at every point in time is ok if we distinguish between temporary and full equilibrium, but I don’t see how there can be a continuum of full equilibria when agents are making all kinds of long-term commitments by investing in specific capital. Having said that, I certainly agree with you that expectational shifts are very important in determining which equilibrium the economy winds up at.

To which Roger responded:

I am comfortable with temporary equilibrium as the guiding principle, as long as the equilibrium in each period is well defined. By that, I mean that, taking expectations as given in each period, each market clears according to some well defined principle. In classical models, that principle is the equality of demand and supply in a Walrasian auction. I do not think that is the right equilibrium concept.

Roger didn’t explain – at least not here, he probably has elsewhere — exactly why he doesn’t think equality of demand and supply in a Walrasian auction is not the right equilibrium concept. But I would be interested in hearing from him why he thinks equality of supply and demand is not the right equilibrium concept. Perhaps he will clarify his thinking for me.

Hicks wanted to separate ‘fix price markets’ from ‘flex price markets’. I don’t think that is the right equilibrium concept either. I prefer to use competitive search equilibrium for the labor market. Search equilibrium leads to indeterminacy because there are not enough prices for the inputs to the search process. Classical search theory closes that gap with an arbitrary Nash bargaining weight. I prefer to close it by making expectations fundamental [a proposition I have advanced on this blog].

I agree that the Hicksian distinction between fix-price markets and flex-price markets doesn’t cut it. Nevertheless, it’s not clear to me that a Thompsonian temporary-equilibrium model in which expectations determine the reservation wage at which workers will accept employment (i.e, the labor-supply curve conditional on the expected wage) doesn’t work as well as a competitive search equilibrium in this context.

Once one treats expectations as fundamental, there is no longer a multiplicity of equilibria. People act in a well defined way and prices clear markets. Of course ‘market clearing’ in a search market may involve unemployment that is considerably higher than the unemployment rate that would be chosen by a social planner. And when there is steady state indeterminacy, as there is in my work, shocks to beliefs may lead the economy to one of a continuum of steady state equilibria.

There is an equilibrium for each set of expectations (with the understanding, I presume, that expectations are always uniform across agents). The problem that I see with this is that there doesn’t seem to be any interaction between outcomes and expectations. Expectations are always self-fulfilling, and changes in expectations are purely exogenous. But in a classic downturn, the process seems to be cumulative, the contraction seemingly feeding on itself, causing a spiral of falling prices, declining output, rising unemployment, and increasing pessimism.

That brings me to the second part of an equilibrium concept. Are expectations rational in the sense that subjective probability measures over future outcomes coincide with realized probability measures? That is not a property of the real world. It is a consistency property for a model.

Yes; I agree totally. Rational expectations is best understood as a property of a model, the property being that if agents expect an equilibrium price vector the solution of the model is the same equilibrium price vector. It is not a substantive theory of expectation formation, the model doesn’t posit that agents correctly foresee the equilibrium price vector, that’s an extreme and unrealistic assumption about how the world actually works, IMHO. The distinction is crucial, but it seems to me that it is largely ignored in practice.

And yes: if we plop our agents down into a stationary environment, their beliefs should eventually coincide with reality.

This seems to me a plausible-sounding assumption for which there is no theoretical proof, and in view of Roger’s recent discussion of unit roots, dubious empirical support.

If the environment changes in an unpredictable way, it is the belief function, a primitive of the model, that guides the economy to a new steady state. And I can envision models where expectations on the transition path are systematically wrong.

I need to read Roger’s papers about this, but I am left wondering by what mechanism the belief function guides the economy to a steady state? It seems to me that the result requires some pretty strong assumptions.

The recent ‘nonlinearity debate’ on the blogs confuses the existence of multiple steady states in a dynamic model with the existence of multiple rational expectations equilibria. Nonlinearity is neither necessary nor sufficient for the existence of multiplicity. A linear model can have a unique indeterminate steady state associated with an infinite dimensional continuum of locally stable rational expectations equilibria. A linear model can also have a continuum of attracting points, each of which is an equilibrium. These are not just curiosities. Both of these properties characterize modern dynamic equilibrium models of the real economy.

I’m afraid that I don’t quite get the distinction that is being made here. Does “multiple steady states in a dynamic model” mean multiple equilibria of the full Arrow-Debreu general equilibrium model? And does “multiple rational-expectations equilibria” mean multiple equilibria conditional on the expectations of the agents? And I also am not sure what the import of this distinction is supposed to be.

My further question is, how does all of this relate to Leijonhfuvud’s idea of the corridor, which Roger has endorsed? My own understanding of what Axel means by the corridor is that the corridor has certain stability properties that keep the economy from careening out of control, i.e. becoming subject to a cumulative dynamic process that does not lead the economy back to the neighborhood of a stable equilibrium. But if there is a continuum of attracting points, each of which is an equilibrium, how could any of those points be understood to be outside the corridor?

Anyway, those are my questions. I am hoping that Roger can enlighten me.

Price Stickiness and Macroeconomics

Noah Smith has a classically snide rejoinder to Stephen Williamson’s outrage at Noah’s Bloomberg paean to price stickiness and to the classic Ball and Maniw article on the subject, an article that provoked an embarrassingly outraged response from Robert Lucas when published over 20 years ago. I don’t know if Lucas ever got over it, but evidently Williamson hasn’t.

Now to be fair, Lucas’s outrage, though misplaced, was understandable, at least if one understands that Lucas was so offended by the ironic tone in which Ball and Mankiw cast themselves as defenders of traditional macroeconomics – including both Keynesians and Monetarists – against the onslaught of “heretics” like Lucas, Sargent, Kydland and Prescott that he just stopped reading after the first few pages and then, in a fit of righteous indignation, wrote a diatribe attacking Ball and Mankiw as religious fanatics trying to halt the progress of science as if that was the real message of the paper – not, to say the least, a very sophisticated reading of what Ball and Mankiw wrote.

While I am not hostile to the idea of price stickiness — one of the most popular posts I have written being an attempt to provide a rationale for the stylized (though controversial) fact that wages are stickier than other input, and most output, prices — it does seem to me that there is something ad hoc and superficial about the idea of price stickiness and about many explanations, including those offered by Ball and Mankiw, for price stickiness. I think that the negative reactions that price stickiness elicits from a lot of economists — and not only from Lucas and Williamson — reflect a feeling that price stickiness is not well grounded in any economic theory.

Let me offer a slightly different criticism of price stickiness as a feature of macroeconomic models, which is simply that although price stickiness is a sufficient condition for inefficient macroeconomic fluctuations, it is not a necessary condition. It is entirely possible that even with highly flexible prices, there would still be inefficient macroeconomic fluctuations. And the reason why price flexibility, by itself, is no guarantee against macroeconomic contractions is that macroeconomic contractions are caused by disequilibrium prices, and disequilibrium prices can prevail regardless of how flexible prices are.

The usual argument is that if prices are free to adjust in response to market forces, they will adjust to balance supply and demand, and an equilibrium will be restored by the automatic adjustment of prices. That is what students are taught in Econ 1. And it is an important lesson, but it is also a “partial” lesson. It is partial, because it applies to a single market that is out of equilibrium. The implicit assumption in that exercise is that nothing else is changing, which means that all other markets — well, not quite all other markets, but I will ignore that nuance – are in equilibrium. That’s what I mean when I say (as I have done before) that just as macroeconomics needs microfoundations, microeconomics needs macrofoundations.

Now it’s pretty easy to show that in a single market with an upward-sloping supply curve and a downward-sloping demand curve, that a price-adjustment rule that raises price when there’s an excess demand and reduces price when there’s an excess supply will lead to an equilibrium market price. But that simple price-adjustment rule is hard to generalize when many markets — not just one — are in disequilibrium, because reducing disequilibrium in one market may actually exacerbate disequilibrium, or create a disequilibrium that wasn’t there before, in another market. Thus, even if there is an equilibrium price vector out there, which, if it were announced to all economic agents, would sustain a general equilibrium in all markets, there is no guarantee that following the standard price-adjustment rule of raising price in markets with an excess demand and reducing price in markets with an excess supply will ultimately lead to the equilibrium price vector. Even more disturbing, the standard price-adjustment rule may not, even under a tatonnement process in which no trading is allowed at disequilibrium prices, lead to the discovery of the equilibrium price vector. Of course, in the real world trading occurs routinely at disequilibrium prices, so that the “mechanical” forces tending an economy toward equilibrium are even weaker than the standard analysis of price-adjustment would suggest.

This doesn’t mean that an economy out of equilibrium has no stabilizing tendencies; it does mean that those stabilizing tendencies are not very well understood, and we have almost no formal theory with which to describe how such an adjustment process leading from disequilibrium to equilibrium actually works. We just assume that such a process exists. Franklin Fisher made this point 30 years ago in an important, but insufficiently appreciated, volume Disequilibrium Foundations of Equilibrium Economics. But the idea goes back even further: to Hayek’s important work on intertemporal equilibrium, especially his classic paper “Economics and Knowledge,” formalized by Hicks in the temporary-equilibrium model described in Value and Capital.

The key point made by Hayek in this context is that there can be an intertemporal equilibrium if and only if all agents formulate their individual plans on the basis of the same expectations of future prices. If their expectations for future prices are not the same, then any plans based on incorrect price expectations will have to be revised, or abandoned altogether, as price expectations are disappointed over time. For price adjustment to lead an economy back to equilibrium, the price adjustment must converge on an equilibrium price vector and on correct price expectations. But, as Hayek understood in 1937, and as Fisher explained in a dense treatise 30 years ago, we have no economic theory that explains how such a price vector, even if it exists, is arrived at, and even under a tannonement process, much less under decentralized price setting. Pinning the blame on this vague thing called price stickiness doesn’t address the deeper underlying theoretical issue.

Of course for Lucas et al. to scoff at price stickiness on these grounds is a bit rich, because Lucas and his followers seem entirely comfortable with assuming that the equilibrium price vector is rationally expected. Indeed, rational expectation of the equilibrium price vector is held up by Lucas as precisely the microfoundation that transformed the unruly field of macroeconomics into a real science.

The Near Irrelevance of the Vertical Long-Run Phillips Curve

From a discussion about how much credit Milton Friedman deserves for changing the way that economists thought about inflation, I want to nudge the conversation in a slightly different direction, to restate a point that I made some time ago in one of my favorite posts (The Lucas Critique Revisited). But if Friedman taught us anything it is that incessant repetition of the same already obvious point can do wonders for your reputation. That’s one lesson from Milton that I am willing to take to heart, though my tolerance for hearing myself say the same darn thing over and over again is probably not as great as Friedman’s was, which to be sure is not the only way in which I fall short of him by comparison. (I am almost a foot taller than he was by the way). Speaking of being a foot taller than Friedman, I don’t usually post pictures on this blog, but here is one that I have always found rather touching. And if you don’t know who the other guy is in the picture, you have no right to call yourself an economist.

friedman_&_StiglerAt any rate, the expectations augmented, long-run Phillips Curve, as we all know, was shown by Friedman to be vertical. But what exactly does it mean for the expectations-augmented, long-run Phillips Curve to be vertical? Discussions about whether the evidence supports the proposition that the expectations-augmented, long-run Phillips Curve is vertical (including some of the comments on my recent posts) suggest that people are not clear on what “long-run” means in the context of the expectations-augmented Phillips Curve and have not really thought carefully about what empirical content is contained by the proposition that the expectations-augmented, long-run Phillips Curve is vertical.

Just to frame the discussion of the Phillips Curve, let’s talk about what the term “long-run” means in economics. What it certainly does not mean is an amount of calendar time, though I won’t deny that there are frequent attempts to correlate long-run with varying durations of calendar time. But all such attempts either completely misunderstand what the long-run actually represents, or they merely aim to provide the untutored with some illusion of concreteness in what is otherwise a completely abstract discussion. In fact, what “long run” connotes is simply a full transition from one equilibrium state to another in the context of a comparative-statics exercise.

If a change in some exogenous parameter is imposed on a pre-existing equilibrium, then the long-run represents the full transition to a new equilibrium in which all endogenous variables have fully adjusted to the parameter change. The short-run, then, refers to some intermediate adjustment to the parameter change in which some endogenous variables have been arbitrarily held fixed (presumably because of some possibly reasonable assumption that some variables are able to adjust more speedily than other variables to the posited parameter change).

Now the Phillips Curve that was discovered by A. W. Phillips in his original paper was a strictly empirical relation between observed (wage) inflation and observed unemployment. But the expectations-augmented long-run Phillips Curve is a theoretical construct. And what it represents is certainly not an observable relationship between inflation and unemployment; it rather is a locus of points of equilibrium, each point representing full adjustment of the labor market to a particular rate of inflation, where full adjustment means that the rate of inflation is fully anticipated by all economic agents in the model. So what the expectations-augmented, long-run Phillips Curve is telling us is that if we perform a series of comparative-statics exercises in which, starting from full equilibrium with the given rate of inflation fully expected, we impose on the system a parameter change in which the exogenously imposed rate of inflation is changed and deduce a new equilibrium in which the fully and universally expected rate of inflation equals the alternative exogenously imposed inflation parameter, the equilibrium rate of unemployment corresponding to the new inflation parameter will not differ from the equilibrium rate of unemployment corresponding to the original inflation parameter.

Notice, as well, that the expectations-augmented, long-run Phillips Curve is not saying that imposing a new rate of inflation on an actual economic system would lead to a new equilibrium in which there was no change in unemployment; it is merely comparing alternative equilibria of the same system with different exogenously imposed rates of inflation. To make a statement about the effect of a change in the rate of inflation on unemployment, one has to be able to specify an adjustment path in moving from one equilibrium to another. The comparative-statics method says nothing about the adjustment path; it simply compares two alternative equilibrium states and specifies the change in endogenous variable induced by the change in an exogenous parameter.

So the vertical shape of the expectations-augmented, long-run Phillips Curve tells us very little about how, in any given situation, a change in the rate of inflation would actually affect the rate of unemployment. Not only does the expectations-augmented long-run Phillips Curve fail to tell us how a real system starting from equilibrium would be affected by a change in the rate of inflation, the underlying comparative-statics exercise being unable to specify the adjustment path taken by a system once it departs from its original equilibrium state, the expectations augmented, long-run Phillips Curve is even less equipped to tell us about the adjustment to a change in the rate of inflation when a system is not even in equilibrium to begin with.

The entire discourse of the expectations-augmented, long-run Phillips Curve is completely divorced from the kinds of questions that policy makers in the real world usually have to struggle with – questions like will increasing the rate of inflation of an economy in which there is abnormally high unemployment facilitate or obstruct the adjustment process that takes the economy back to a more normal unemployment rate. The expectations-augmented, long-run Phillips Curve may not be completely irrelevant to the making of economic policy – it is good to know, for example, that if we are trying to figure out which time path of NGDP to aim for, there is no particular reason to think that a time path with a 10% rate of growth of NGDP would probably not generate a significantly lower rate of unemployment than a time path with a 5% rate of growth – but its relationship to reality is sufficiently tenuous that it is irrelevant to any discussion of policy alternatives for economies unless those economies are already close to being in equilibrium.

Krugman on the Volcker Disinflation

Earlier in the week, Paul Krugman wrote about the Volcker disinflation of the 1980s. Krugman’s annoyance at Stephen Moore (whom Krugman flatters by calling him an economist) and John Cochrane (whom Krugman disflatters by comparing him to Stephen Moore) is understandable, but he has less excuse for letting himself get carried away in an outburst of Keynesian triumphalism.

Right-wing economists like Stephen Moore and John Cochrane — it’s becoming ever harder to tell the difference — have some curious beliefs about history. One of those beliefs is that the experience of disinflation in the 1980s was a huge shock to Keynesians, refuting everything they believed. What makes this belief curious is that it’s the exact opposite of the truth. Keynesians came into the Volcker disinflation — yes, it was mainly the Fed’s doing, not Reagan’s — with a standard, indeed textbook, model of what should happen. And events matched their expectations almost precisely.

I’ve been cleaning out my library, and just unearthed my copy of Dornbusch and Fischer’s Macroeconomics, first edition, copyright 1978. Quite a lot of that book was concerned with inflation and disinflation, using an adaptive-expectations Phillips curve — that is, an assumed relationship in which the current inflation rate depends on the unemployment rate and on lagged inflation. Using that approach, they laid out at some length various scenarios for a strategy of reducing the rate of money growth, and hence eventually reducing inflation. Here’s one of their charts, with the top half showing inflation and the bottom half showing unemployment:

Not the cleanest dynamics in the world, but the basic point should be clear: cutting inflation would require a temporary surge in unemployment. Eventually, however, unemployment could come back down to more or less its original level; this temporary surge in unemployment would deliver a permanent reduction in the inflation rate, because it would change expectations.

And here’s what the Volcker disinflation actually looked like:

A temporary but huge surge in unemployment, with inflation coming down to a sustained lower level.

So were Keynesian economists feeling amazed and dismayed by the events of the 1980s? On the contrary, they were feeling pretty smug: disinflation had played out exactly the way the models in their textbooks said it should.

Well, this is true, but only up to a point. What Krugman neglects to mention, which is why the Volcker disinflation is not widely viewed as having enhanced the Keynesian forecasting record, is that most Keynesians had opposed the Reagan tax cuts, and one of their main arguments was that the tax cuts would be inflationary. However, in the Reagan-Volcker combination of loose fiscal policy and tight money, it was tight money that dominated. Score one for the Monetarists. The rapid drop in inflation, though accompanied by high unemployment, was viewed as a vindication of the Monetarist view that inflation is always and everywhere a monetary phenomenon, a view which now seems pretty commonplace, but in the 1970s and 1980s was hotly contested, including by Keynesians.

However, the (Friedmanian) Monetarist view was only partially vindicated, because the Volcker disinflation was achieved by way of high interest rates not by tightly controlling the money supply. As I have written before on this blog (here and here) and in chapter 10 of my book on free banking (especially, pp. 214-21), Volcker actually tried very hard to slow down the rate of growth in the money supply, but the attempt to implement a k-percent rule induced perverse dynamics, creating a precautionary demand for money whenever monetary growth overshot the target range, the anticipation of an imminent future tightening causing people, fearful that cash would soon be unavailable, to hoard cash by liquidating assets before the tightening. The scenario played itself out repeatedly in the 1981-82 period, when the most closely watched economic or financial statistic in the world was the Fed’s weekly report of growth in the money supply, with growth rates over the target range being associated with falling stock and commodities prices. Finally, in the summer of 1982, Volcker announced that the Fed would stop trying to achieve its money growth targets, and the great stock market rally of the 1980s took off, and economic recovery quickly followed.

So neither the old-line Keynesian dismissal of monetary policy as irrelevant to the control of inflation, nor the Monetarist obsession with controlling the monetary aggregates fared very well in the aftermath of the Volcker disinflation. The result was the New Keynesian focus on monetary policy as the key tool for macroeconomic stabilization, except that monetary policy no longer meant controlling a targeted monetary aggregate, but controlling a targeted interest rate (as in the Taylor rule).

But Krugman doesn’t mention any of this, focusing instead on the conflicts among  non-Keynesians.

Indeed, it was the other side of the macro divide that was left scrambling for answers. The models Chicago was promoting in the 1970s, based on the work of Robert Lucas and company, said that unemployment should have come down quickly, as soon as people realized that the Fed really was bringing down inflation.

Lucas came to Chicago in 1975, and he was the wave of the future at Chicago, but it’s not as if Friedman disappeared; after all, he did win the Nobel Prize in 1976. And although Friedman did not explicitly attack Lucas, it’s clear that, to his credit, Friedman never bought into the rational-expectations revolution. So although Friedman may have been surprised at the depth of the 1981-82 recession – in part attributable to the perverse effects of the money-supply targeting he had convinced the Fed to adopt – the adaptive-expectations model in the Dornbusch-Fischer macro textbook is as much Friedmanian as Keynesian. And by the way, Dornbush and Fischer were both at Chicago in the mid 1970s when the first edition of their macro text was written.

By a few years into the 80s it was obvious that those models were unsustainable in the face of the data. But rather than admit that their dismissal of Keynes was premature, most of those guys went into real business cycle theory — basically, denying that the Fed had anything to do with recessions. And from there they just kept digging ever deeper into the rabbit hole.

But anyway, what you need to know is that the 80s were actually a decade of Keynesian analysis triumphant.

I am just as appalled as Krugman by the real-business-cycle episode, but it was as much a rejection of Friedman, and of all other non-Keynesian monetary theory, as of Keynes. So the inspiring morality tale spun by Krugman in which the hardy band of true-blue Keynesians prevail against those nasty new classical barbarians is a bit overdone and vastly oversimplified.

Hicks on IS-LM and Temporary Equilibrium

Jan, commenting on my recent post about Krugman, Minsky and IS-LM, quoted the penultimate paragraph of J. R. Hicks’s 1980 paper on IS-LM in the Journal of Post-Keynesian Economics, a brand of economics not particularly sympathetic to Hicks’s invention. Hicks explained that in the mid-1930s he had been thinking along lines similar to Keynes’s even before the General Theory was published, and had the basic idea of IS-LM in his mind even before he had read the General Theory, while also acknowledging that his enthusiasm for the IS-LM construct had waned considerably over the years.

Hicks discussed both the similarities and the differences between his model and IS-LM. But as the discussion proceeds, it becomes clear that what he is thinking of as his model is what became his model of temporary equilibrium in Value and Capital. So it really is important to understand what Hicks felt were the similarities as well as the key differences between the temporary- equilibrium model, and the IS-LM model. Here is how Hicks put it:

I recognized immediately, as soon as I read The General Theory, that my model and Keynes’ had some things in common. Both of us fixed our attention on the behavior of an economy during a period—a period that had a past, which nothing that was done during the period could alter, and a future, which during the period was unknown. Expectations of the future would nevertheless affect what happened during the period. Neither of us made any assumption about “rational expectations” ; expectations, in our models, were strictly exogenous.3 (Keynes made much more fuss over that than I did, but there is the same implication in my model also.) Subject to these data— the given equipment carried over from the past, the production possibilities within the period, the preference schedules, and the given expectations— the actual performance of the economy within the period was supposed to be determined, or determinable. It would be determined as an equilibrium performance, with respect to these data.

There was all this in common between my model and Keynes'; it was enough to make me recognize, as soon as I saw The General Theory, that his model was a relation of mine and, as such, one which I could warmly welcome. There were, however, two differences, on which (as we shall see) much depends. The more obvious difference was that mine was a flexprice model, a perfect competition model, in which all prices were flexible, while in Keynes’ the level of money wages (at least) was exogenously determined. So Keynes’ was a model that was consistent with unemployment, while mine, in his terms, was a full employment model. I shall have much to say about this difference, but I may as well note, at the start, that I do not think it matters much. I did not think, even in 1936, that it mattered much. IS-LM was in fact a translation of Keynes’ nonflexprice model into my terms. It seemed to me already that that could be done; but how it is done requires explanation.

The other difference is more fundamental; it concerns the length of the period. Keynes’ (he said) was a “short-period,” a term with connotations derived from Marshall; we shall not go far wrong if we think of it as a year. Mine was an “ultra-short-period” ; I called it a week. Much more can happen in a year than in a week; Keynes has to allow for quite a lot of things to happen. I wanted to avoid so much happening, so that my (flexprice) markets could reflect propensities (and expectations) as they are at a moment. So it was that I made my markets open only on a Monday; what actually happened during the ensuing week was not to affect them. This was a very artificial device, not (I would think now) much to be recommended. But the point of it was to exclude the things which might happen, and must disturb the markets, during a period of finite length; and this, as we shall see, is a very real trouble in Keynes. (pp. 139-40)

Hicks then explained how the specific idea of the IS-LM model came to him as a result of working on a three-good Walrasian system in which the solution could be described in terms of equilibrium in two markets, the third market necessarily being in equilibrium if the other two were in equilibrium. That’s an interesting historical tidbit, but the point that I want to discuss is what I think is Hicks’s failure to fully understand the significance of his own model, whose importance, regrettably, he consistently underestimated in later work (e.g., in Capital and Growth and in this paper).

The point that I want to focus on is in the second paragraph quoted above where Hicks says “mine [i.e. temporary equilibrium] was a flexprice model, a perfect competition model, in which all prices were flexible, while in Keynes’ the level of money wages (at least) was exogenously determined. So Keynes’ was a model that was consistent with unemployment, while mine, in his terms, was a full employment model.” This, it seems to me, is all wrong, because Hicks, is taking a very naïve and misguided view of what perfect competition and flexible prices mean. Those terms are often mistakenly assumed to meant that if prices are simply allowed to adjust freely, all  markets will clear and all resources will be utilized.

I think that is a total misconception, and the significance of the temporary-equilibrium construct is in helping us understand why an economy can operate sub-optimally with idle resources even when there is perfect competition and markets “clear.” What prevents optimality and allows resources to remain idle despite freely adjustming prices and perfect competition is that the expectations held by agents are not consistent. If expectations are not consistent, the plans based on those expectations are not consistent. If plans are not consistent, then how can one expect resources to be used optimally or even at all? Thus, for Hicks to assert, casually without explicit qualification, that his temporary-equilibrium model was a full-employment model, indicates to me that Hicks was unaware of the deeper significance of his own model.

If we take a full equilibrium as our benchmark, and look at how one of the markets in that full equilibrium clears, we can imagine the equilibrium as the intersection of a supply curve and a demand curve, whose positions in the standard price/quantity space depend on the price expectations of suppliers and of demanders. Different, i.e, inconsistent, price expectations would imply shifts in both the demand and supply curves from those corresponding to full intertemporal equilibrium. Overall, the price expectations consistent with a full intertemporal equilibrium will in some sense maximize total output and employment, so when price expectations are inconsistent with full intertemporal equilibrium, the shifts of the demand and supply curves will be such that they will intersect at points corresponding to less output and less employment than would have been the case in full intertemporal equilibrium. In fact, it is possible to imagine that expectations on the supply side and the demand side are so inconsistent that the point of intersection between the demand and supply curves corresponds to an output (and hence employment) that is way less than it would have been in full intertemporal equilibrium. The problem is not that the price in the market doesn’t allow the market to clear. Rather, given the positions of the demand and supply curves, their point of intersection implies a low output, because inconsistent price expectations are such that potentially advantageous trading opportunities are not being recognized.

So for Hicks to assert that his flexprice temporary-equilibrium model was (in Keynes’s terms) a full-employment model without noting the possibility of a significant contraction of output (and employment) in a perfectly competitive flexprice temporary-equilibrium model when there are significant inconsistencies in expectations suggests strongly that Hicks somehow did not fully comprehend what his own creation was all about. His failure to comprehend his own model also explains why he felt the need to abandon the flexprice temporary-equilibrium model in his later work for a fixprice model.

There is, of course, a lot more to be said about all this, and Hicks’s comments concerning the choice of a length of the period are also of interest, but the clear (or so it seems to me) misunderstanding by Hicks of what is entailed by a flexprice temporary equilibrium is an important point to recognize in evaluating both Hicks’s work and his commentary on that work and its relation to Keynes.

About Me

David Glasner
Washington, DC

I am an economist at the Federal Trade Commission. Nothing that you read on this blog necessarily reflects the views of the FTC or the individual commissioners. Although I work at the FTC as an antitrust economist, most of my research and writing has been on monetary economics and policy and the history of monetary theory. 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.

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