Must-Read: Simon Wren-Lewis: Helicopter Money and Fiscal Policy

Must-Read: What I often hear: “Expansionary fiscal policy increases the burden of the national debt. That’s the reason expansionary fiscal policy is too risky. Helicopter money–social credit–is expansionary fiscal policy. But expansionary fiscal policy is too risky. Hence helicopter money is too risky.”

Stupid or evil? Simon Wren-Lewis does some intellectual garbage collection:

Simon Wren-Lewis: Helicopter Money and Fiscal Policy: “John Kay and Joerg Bibow think additional government spending on public investment is a good idea…

…We can have endless debates about whether HM is more monetary or fiscal. While attempts to distinguish… can sometime clarify… ultimately… HM is what it is. Arguments that… use definitions to… conclude that central banks should not do HM because it’s fiscal are equally pointless. Any HM distribution mechanism needs to be set up in agreement with governments, and existing monetary policy has fiscal consequences which governments have no control over…..

At this moment in time… public investment should increase in the US, UK and Eurozone. There is absolutely no reason why that cannot be financed by issuing government debt…. HM does not stop the government doing what it wants with fiscal policy. Monetary policy adapts to whatever fiscal policy plans the government has, and it can do this because it can move faster than governments…. Kay… also suggests that HM is somehow a way of getting politicians to do fiscal stimulus by calling it something else. This seems to ignore why fiscal stimulus ended. In 2010 both Osborne and Merkel argued we had to reduce government borrowing immediately because the markets demanded it. HM… avoids the constraint that Osborne and Merkel said prevented further fiscal stimulus…. Many argue that these concerns about debt are manufactured… deficit deceit. HM, particularly in its democratic form, calls their bluff….

There is a related point in favour of HM that both Kay and Bibow miss. Independent central banks are a means of delegating macroeconomic stabilisation. Yet that delegation is crucially incomplete, because of the lower bound for nominal interest rates. While economists have generally understood that governments can in this situation come to the rescue, politicians either didn’t get the memo, or have proved that they are indeed not to be trusted with the task. HM is a much better instrument than Quantitative Easing, so why deny central banks the instrument they require to do the job they have been asked to do?

Must-read: Ryan Avent: “The Fed Ruins Summer: America’s Central Bank Picks a Poor Time to Get Hawkish”

Must-Read: And agreement on my read of the Federal Reserve from the very sharp Ryan Avent. Nice to know that I am not crazy, or not that crazy…

Ryan Avent: The Fed Ruins Summer: America’s Central Bank Picks a Poor Time to Get Hawkish: “THE… Federal Reserve… ha[s] been desperate to hike rates, often…

…keen to begin hiking in September, but were put off when market volatility threatened to undermine the American recovery. In December they managed to get the first increase on the books, and committee members were feeling cocky as 2016 began; Stanley Fischer, the vice-chairman, proclaimed that it would be a four-hike year… and here we are in mid-May with just the one, December rise behind us. But the Fed… is ready to give higher rates another chance…. Every Fed official to wander within range of a microphone warned that more rate hikes might be coming sooner than many people anticipate. And yesterday the Fed published minutes from its April meeting which were revealing:

Most participants judged that if incoming data were consistent with economic growth picking up…then it likely would be appropriate for the Committee to increase the target range for the federal funds rate in June….

[But] worries about runaway inflation are based on a view of the relationship between inflation and unemployment that looks shakier by the day…. Global labour and product markets are glutted… a global glut of investable savings too…. The Fed does not have cause to try to push inflation down. Its preferred measure of inflation continues to run below the Fed’s 2% target, as it has for the last four years. Somehow the Fed seems not to worry about what effect that might have on its credibility. All that undershooting has depressed market-based measures of inflation expectations…. If the Fed’s goal is to hit the 2% target in expectation, or on average, or most of the time, or every once in a while, or ever again, it might consider holding off on another rate rise until the magical 2% figure is reached. You know, just to make sure it can be done.

But the single biggest, overwhelming, really important reason not to rush this is the asymmetry of risks facing the central bank. Actually, the Fed’s economic staff explains this well; from the minutes:

The risks to the forecast for real GDP were seen as tilted to the downside, reflecting the staff’s assessment that neither monetary nor fiscal policy was well positioned to help the economy withstand substantial adverse shocks. In addition, while there had been recent improvements in global financial and economic conditions, downside risks to the forecast from developments abroad, though smaller, remained. Consistent with the downside risk to aggregate demand, the staff viewed the risks to its outlook for the unemployment rate as skewed to the upside.

The Fed has unlimited room to raise interest rates…. It has almost no room to reduce rates…. Hiking now is a leap off a cliff in a fog; one could always wait and jump later once conditions are clearer, but having jumped blindly one cannot reverse course if the expected ledge isn’t where one thought it would be…

I Continue to Fail to Understand Why the Federal Reserve’s Read of Optimal Monetary Policy Is so Different from Mine…

Does you think this looks like an economy where inflation is on an upward trend and interest rates are too low for macroeconomic balance?

Personal Consumption Expenditures Chain type Price Index FRED St Louis Fed Graph Personal Consumption Expenditures Excluding Food and Energy Chain Type Price Index FRED St Louis Fed

Mohamed El-Erian says, accurately, that the Federal Reserve is much more likely than not to increase interest rates in June or July: Mohamed El-Erian: Federal Reserve Is Torn: “”Moves in financial conditions as a whole are making [the Fed]…

…more confident about going forward [with interest-rate hikes,] and they were worried that the markets were underestimating the possibility of a rate hike this year and they wanted to do something about it…. In the end, what’s clear is a hike will definitely happen this year…. If the Fed unambiguously signals that it will move, you will see a stronger dollar and that… will have consequences on other markets…

Olivier Blanchard (2016), [Blanchard, Cerutti, and Summers (2015)2, Kiley (2015), IMF (2013), and Ball and Mazumder (2011) all tell us this about the Phillips Curve:

  • The best estimates of the Phillips Curve as it stood in the 1970s is that, back in the day, an unemployment rate 1%-point less than the NAIRU maintained for 1.5 years would raise the inflation rate by 1%-point, and that a 1%-point increase in inflation would raise future expected inflation by 0.8%-points.
  • The best estimates of the Phillips as it stands today is that, here and now, an unemployment rate 1%-point less than the NAIRU maintained for 5 years would raise the inflation rate by 1%-point, and that a 1%-point increase in inflation would raise future expected inflation by 0.15%-points.
Www bradford delong com 2016 01 must read olivier blanchard says that he and paul krugman differ not at all on the analytics but rather substantially html

In only 6 of the last 36 months has the PCE core inflation rate exceeded 2.0%/year. I keep calling for someone to present me with any sort of optimal-control exercise that leads to the conclusion that it is appropriate for the Federal Reserve to be raising interest rights right now.

Civilian Employment Population Ratio FRED St Louis Fed

I keep hearing nothing but crickets

My worries are compounded by the fact that the Federal Reserve appears to be working with an outmoded and probably wrong model of how monetary policy affects the rest of the world under floating exchange rates. The standard open-economy flexible-exchange rate models I was taught at the start of the 1980s said that contractionary monetary policy at home had an expansionary impact abroad: the dominant effect was to raise the value of the home currency and thus boost foreign countries’ levels of aggregate demand through the exports channel. But [Blanchard, Ostry, Ghosh, and Chamon (2015)][6] argue, convincingly, that that is more likely than not to be wrong: when the Fed or any other sovereign reserve currency-issuer with exorbitant privilege raises dollar interest rates, that drains risk-bearing capacity out of the rest of the world economy, and the resulting increase in interest-rate spreads puts more downward pressure on investment than there is upward pressure on exports.

It looks to me as though the Fed is thinking that its desire to appease those in the banking sector and elsewhere who think, for some reason, that more “normal” and higher interest rates now are desirable is not in conflict with its duty as global monetary hegemon in a world afflicted with slack demand. But it looks more likely than not that they are in fact in conflict.

[6]: Blanchard, Jonathan D. Ostry, Atish R. Ghosh, and Marcos Chamon

Must-read: Tim Duy: Fed Watch: Fed Speak, Claims

Must-Read: I confess I could understand FOMC participants wanting to raise interest rates right now if projected growth over 2016 was 3.5% or higher. But we have a first quarter of 0.8% and a second quarter of 2.3%: we may well not even get to 2.0% this year.

I confess I understand FOMC participants worrying about “imbalances” created by extremely-low interest rates, but:

  1. If they are worried about extremely-low real interest rates, they need to be all-in pressuring the Congress for more expansionary fiscal policy.

  2. If they are worried about extremely-low nominal interest rates, they need to be all-in pressuring their colleagues for a higher inflation target.

It’s the absence of either of those two from the Fed hawks–and the Fed moderates–that has me greatly concerned:

Tim Duy: Fed Watch: Fed Speak, Claims: “The Fed is not likely to raise rates in June…

…But not everyone at the Fed is on board with the plan. Serial dissenter Kansas City Federal Reserve President Esther George repeated her warnings that interest rates are too low…. Boston Federal Reserve President Eric Rosengren… reiterated his warning that financial markets just don’t get it….

I would suggest that the failure of policymakers to better manage the economy at turning points is not because it is impossible, but because they have overtightened in the latter stage of the cycle, forgetting to pay attention to the lags in policy they think are so important during the early stages of the cycle….

Bottom Line: Ultimately, I suspect the FOMC will not find sufficient reason in the data before June to convince the Fed that growth is sufficiently strong to justify a hike. Hence I anticipate that they will pass on that opportunity to raise rates. Look for an opportunity in September…. I doubt, however, that most on the Fed are pleased that market participants have already priced out a June hike on the basis of the April employment report…. They do not see the outcome as already preordained.

On the definition of a “liquidity trap”

I am going to split hairs with Robert Waldmann here…

Robert writes:

Robert Waldmann: The USA is not in a liquidity trap any more: “The output gap can be [estimated] by attempting to measure slack directly…

…The ratio of employment to prime age (25-54) population… is very low…. The ratio of vacant jobs to employment is very high, the quit rate is normal and real wages have begun to grow. The pattern is very confusing… it is possible for the same person to reach very different conclusions on different days….

[But] we [do not] need to estimate the output gap to predict the Fed’s response to fiscal stimulus…. The Fed Open Market Committee (FOMC) has… made it very clear that they are considering further rate increases. It could not be more clear that markedly reduced unemployment will convince them to raise interest rates. The US economy is not at the zero lower bound anymore. This just means that the FOMC no longer wishes it could achieve a negative federal funds rate…. This is a statement about what the FOMC will do not what it should do…

Let me disagree with Robert.

Whether or not the short-term safe nominal interest rate that the central bank controls is zero or not, an economy is in a liquidity trap when:

  • even a zero interest rate is not sufficient to raise planned expenditure to the level of full-employment output.

The central bank could be pegging the Fed Funds rate at 5%, and the economy would still be in a liquidity trap if even a 0% rate was insufficient to restore full employment.

Now there is disagreement about whether the U.S. economy is in a liquidity trap right now. The Federal Reserve doesn’t think so: the Federal Reserve thinks the current short-term safe nominal Wicksellian neutral interest rate is 0.25%. But I think that the Federal Reserve is wrong. And if the Federal Reserve is wrong–if the short-term safe nominal Wicksellian neutral interest rate is still less than zero–the economy is still in a liquidity trap, even though the Federal Reserve does not think that it is.

This bears on the question of whether expansionary fiscal policy is a good thing or not. If indeed the economy still is in a liquidity trap, the Federal Reserve will learn–in which case expansionary fiscal policy now will be beneficial, as it will save them from the consequences of their current mistakes as they learn and adjust. If the economy is not in a liquidity trap, expansionary fiscal policy will still raise the neutral interest rate–and so provide the Federal Reserve with more sea-room and a much better chance of avoiding another zero lower-bound catastrophe when the next adverse macroeconomic shock hits.

To say: “Because the Fed has raised the Fed Funds rate above zero, we are no longer in a liquidity trap, and expansionary fiscal policy no longer has a point” is, I think, to fundamentally mis-analyze the situation…

Must-read: Gary Gorton: “The History and Economics of Safe Assets”

Must-Read: Gary B. Gorton: The History and Economics of Safe Assets: “Safe assets play a critical role in an(y) economy…

…A ‘safe asset’ is an asset that is (almost always) valued at face value without expensive and prolonged analysis. That is, by design there is no benefit to producing (private) information about its value. And this is common knowledge. Consequently, agents need not fear adverse selection when buying or selling safe assets. Safe assets can easily be used to exchange for goods or services or to exchange for another asset. These short-term safe assets are money or money-like. A long-term safe asset can store value over time or be used as collateral. Human history can be written in terms of the search for and production of safe assets. But, the most prevalent, privately-produced short-term safe assets—bank debt, are subject to runs and this has important implications for macroeconomics and for monetary policy.

Regress in macroeconomic knowledge over the past 83 years

Today, in 2016, Raghu Rajan thinks helicopter drops are “a step too far into the dark…”

His predecessor 83 years ago at the University of Chicago, Jacob Viner, thought they were one of the obvious technocratic steps to take, along with further raising the monetary base (i.e., in his day going off of the gold standard) even with short-term safe nominal interest rates at the zero lower bound (as they also were in his day).

Here’s Raghu:

Raghuram Rajan 2016): “If you read the writings of economists…

…it is not clear what’s keeping us still so slow, seven or eight years after the crisis. Ken Rogoff would say it is still the debt overhang and the deleveraging. [Robert] Gordon and others might say it is low productivity and still others may say it is the poorly understood consequences of population aging. But what do we do? And here I think there is more of a consensus that monetary policy pretty much has run its course. There are still guys who are looking for helicopter drops of money but I think that is a step sort of too far into the dark, where I am not sure there is a political consensus to do that in the major economies, if it comes to that…

Here’s Jacob:

Jacob Viner (1933): Balanced Deflation, Inflation, or More Deflation: “If going off the gold standard were as simple a matter for us…

…as for England and Canada, I would not only advocate it, but if [it]… did not suffice to lower substantially the internal purchasing power of the dollar I would recommend its accompaniment by increased government expenditures financed by the printing press or by loans…. England and… the other countries which went off the gold standard in 1931… [made] too restrained use of the freedom which the departure from the gold standard gave them them…. The countries that went off the gold standard have nevertheless weathered the economic storm much better…

We all agree that economies today are “so slow” and inflation pressures are by and large absent. What does Raghu think he knows today that Jacob did not–what have we learned in the past 83 years–that has turned helicopter drops from an obvious technocratic step to take to “a step too far into the dark”? What did Jacob think he knew that Raghu does not–what doctrines, true, false, or uncertain–because we have forgotten them?

Anyone? Anyone? Bueller?

Yes, in some (many) ways, our macro debate has lost intellectual ground since the 1930s. Why do you ask?

Last September, the illustrious Simon Wren-Lewis wrote a nice piece about the Bank of England’s thinking about Quantitative Easing: Haldane on Alternatives to QE, and What He Missed Out.

Simon’s bottom line was that Haldane was not just thinking inside the box, but restricting his thinking to a very small corner of the box:

[neither] discussion of the possibility that targeting something other than inflation might help… [nor] any discussion of helicopter money…

And this disturbs him because:

We rule out helicopter money because its undemocratic, but we rule out a discussion of helicopter money because ordinary people might like the idea…. Governments around the world have gone for fiscal contraction because of worries about the immediate prospects for debt. It is not as if the possibility of helicopter money restricts the abilities of governments in any way…. [While] it is good that some people at the Bank are thinking about alternatives to QE, which is a lousy instrument…. It is a shame that the Bank is not even acknowledging that there is a straightforward and cost-free solution…

It disturbs me too.

One reason it disturbs me is that a version of “helicopter money” was one of the policy options that Milton Friedman and Jacob Viner endorsed as the right policies to deal with the last time we were at the zero lower bound, stock Great Depression. Back in 2009 I quoted Milton Friedman (1972), “Comments on the Critics of ‘Milton Friedman’s Monetary Framework'”, quoting Jacob Viner (1933):

The simplest and least objectionable procedure would be for the federal government to increase its expenditures or to decrease its taxes, and to finance the resultant excess of expenditures over tax revenues either by the issue of legal tender greenbacks or by borrowing from the banks..

And Friedman continued:

[Abba] Lerner was trained at the London School of Economics [stock 1930s], where the dominant view was that the depression was an inevitable result of the prior [speculative] boom, that it was deepened by the attempts to prevent prices and wages from falling and firms from going bankrupt, that the monetary authorities had brought on the depression by inflationary policies before the crash and had prolonged it by “easy money” policies thereafter; that the only sound policy was to let the depression run its course, bring down money costs, and eliminate weak and unsound firms…. It was [this] London School (really Austrian) view that I referred to in my “Restatement” when I spoke of “the atrophied and rigid caricature [of the quantity theory] that is so frequently described by the proponents of the new income-expenditure approach and with some justice, to judge by much of the literature on policy that was spawned by the quantity theorists” (Friedman 1969, p. 51).

The intellectual climate at Chicago had been wholly different. My teachers… blamed the monetary and fiscal authorities for permitting banks to fail and the quantity of deposits to decline. Far from preaching the need to let deflation and bankruptcy run their course, they issued repeated pronunciamentos calling for governmental action to stem the deflation-as J. Rennie Davis put it:

Frank H. Knight, Henry Simons, Jacob Viner, and their Chicago colleagues argued throughout the early 1930’s for the use of large and continuous deficit budgets to combat the mass unemployment and deflation of the times (Davis 1968, p. 476)… that the Federal Reserve banks systematically pursue open-market operations with the double aim of facilitating necessary government financing and increasing the liquidity of the banking structure (Wright 1932, p. 162)….

Keynes had nothing to offer those of us who had sat at the feet of Simons, Mints, Knight, and Viner. It was this view of the quantity theory that I referred to in my “Restatement” as “a more subtle and relevant version, one in which the quantity theory was connected and integrated with general price theory and became a flexible and sensitive tool for interpreting movements in aggregate economic activity and for developing relevant policy prescriptions” (Friedman 1969, p. 52). I do not claim that this more hopeful and “relevant” view was restricted to Chicago. The manifesto from which I have quoted the recommendation for open-market operations was issued at the Harris Foundation lectures held at the University of Chicago in January 1932 and was signed by twelve University of Chicago economists. But there were twelve other signers (including Irving Fisher of Yale, Alvin Hansen of Minnesota, and John H. Williams of Harvard) from nine other institutions’…

“Helicopter money”–increases in the money stock used not to buy back securities but instead to purchase assets that are very bad substitutes for cash like the consumption expenditures of households, roads and bridges, the human capital of 12-year-olds, and biomedical research–could be mentioned as a matter of course as a desirable policy for dealing with an economy at the zero lower bound by Jacob Viner in 1933. But, apparently, central banks do not even want to whisper about the possibility. One interpretation is that, confronted with Treasury departments backed by politicians and elected by voters that have a ferocious and senseless jones for austerity even though g > r, central banks fear that any additional public recognition by them that fiscal and monetary policy blur into each other may attract the Eye of Austerity and so limit their independence and freedom of action.

If I were on the Federal Reserve Board of Governors or in the Court of the Bank of England right now, I would be taking every step to draw the line between fiscal policy and monetary policy sharply, but I would draw it in the obvious place:

  • Contractionary fiscal policies seek to lower the government debt (but with g > r or even g near r and hysteresis actually raise the debt-to-GDP ratio and possibly the debt).
  • Expansionary fiscal policies seek to raise the government debt (but with g > r or even g near r and hysteresis actually lower the debt-to-GDP ratio and possibly the debt).
  • Policies that neither raise or lower the debt ain’t fiscal policy, they are monetary policy.
  • Contractionary monetary policies reduce the money stock (and usually but do not have to raise the stock of government debt held by the private sector).
  • Expansionary monetary policies raise the money stock (and usually but do not have to lower the stock of government debt held by the private sector).

And if helicopter money leads Treasuries to protest that the money stock is growing too rapidly? (They cannot, after all, complain that the government debt stock is growing too rapidly because it isn’t.) The response is: Who died and put you in charge of monetary inflation-control policy? That’s not your business.

Monday Smackdown: Robert Waldmann Marks Brad DeLong’s Beliefs about “The Return of Depression Economics” to Market

Robert Waldmann: Brad DeLong Marks His Beliefs about “The Return of Depression Economics” to Market: “Brad DeLong…reposted his review of Krugman’s ‘The Return of Depression Economics’ from 1999…

…’Just in case I get a swelled-head and think I am right more often than I am …’ Way back in the last century, Brad thought he had a valid criticism of Paul Krugman’s argument that Japan (and more generally countries in a liquidity trap) need higher expected inflation. I think the re-post is not just admirable as a self criticism session, but also shows us something about the power of Macroeconomic orthodoxy. Brad is just about as unorthodox as an economist can be without being banished from the profession, but even he was more influenced by Milton Friedman and Robert Lucas than he should have been…. Japan had slack aggregate demand at a safe nominal interest rate of 0–that i,s it was in the liquidity trap. Krugman argued that higher expected inflation would cause negative expected real interest rates and higher aggregate demand and solve the problem. Brad was unconvinced (way back then):

But at this point Krugman doesn’t have all the answers. For while the fact of regular, moderate inflation would certainly boost aggregate demand for products made in Japan, the expectation of inflation would cause an adverse shift in aggregate supply: firms and workers would demand higher prices and wages in anticipation of the inflation they expected would occur, and this increase in costs would diminish how much real production and employment would be generated by any particular level of aggregate demand.

Would the benefits on the demand side from the fact of regular moderate inflation outweigh the costs on the supply side of a general expectation that Japan is about to resort to deliberate inflationary finance? Probably. I’m with Krugman on this one. But it is just a guess–it is not my field of expertise–I would want to spend a year examining the macroeconomic structure of the Japanese economy in detail before I would be willing to claim even that my guess was an informed guess.

And there is another problem. Suppose that investors do not see the fact of inflation–suppose that Japan does not adopt inflationary finance–but that a drumbeat of advocates claiming that inflation is necessary causes firms and workers to mark up prices and wages. Then we have the supply-side costs but not the demand-side benefits, and so we are worse off than before.

As Brad now notes, this argument makes no sense. I think it might be hard for people who learned about macro in the age of the liquidity trap to understand what he had in mind. I also think the passage might risk being convincing to people who haven’t read enough Krugman or Keynes. The key problems in the first paragraphs are ‘adverse’ and ‘any particular level of aggregate demand’. Brad assumed that an increase in wage and price demands is an adverse shift. The argument that it is depends on the assumption that he can consider a fixed level of nominal aggregate demand (and yet he didn’t feel the need to put in the word ‘nominal’). The butchered sentence ‘would diminish how much real production and employment would be generated by any particular level of [real] aggregate demand.’ clearly makes no sense.

During the 80s, new Keynesian macroeconomists got into the habit of considering a fixed level of nominal aggregate demand when focusing on aggregate supply. Because it wasn’t the focus, they used the simplest existing model of aggregate demand the rigid quantity theory of money in which nominal aggregate demand is a constant times the money supply (which is assumed to be set by the monetary authority). This means that the aggregate demand curve (price level on the y axis and real gdp on the x axis) slopes down. This in turn means that an upward shift in the aggregate supply curve is an adverse shift.

More generally, the way in which a higher price level causes lower real aggregate demand is by reducing the real value of the money supply, but if the economy is in the liquidity trap the reduction in the real money supply has no effect on aggregate demand. In the case considered by Krugman, the aggregate demand curve is vertical. This means that he can discuss the effect of policy on real GDP without considering the aggregate supply curve. The second paragraph just repeats the assumption that higher expected inflation causes ‘costs’. There are no such costs (at least according to current and then existing theory) if the economy is in a liquidity trap. The third paragraph shows confusion about the cause of the ‘demand side benefits’. They are caused by higher expected inflation not by higher actual inflation. If there were higher expected inflation not followed by higher actual inflation, Japan would enjoy the benefits anyway. Those benefits would outweigh the non-existent costs.

Krugman actually did consider a model of aggregate supply, but it is so simple it is easy to miss. As usual (well as became usual as Krugman did this again and again) the model has two periods–the present and the long run. In the present, it is assumed that wages and prices are fixed. In the long run it is assumed that there is full employment and constant inflation. Krugman’s point is that all of the important differences between old Keynesian models and models with rational forward looking agents can be understood with just two periods and very simple math. The problem is that the math is so simple that it is easy to not notice it is there and to assume that he ignored the supply side.

I am going to be dumb (I am not playing dumb–I just worked through each step) and consider different less elegant models of aggregate supply. The following will be extremely boring and pointless:

  1. Fixed nominal wages, flexible prices and profit maximization (this is Keynes’s implicit model of aggregate supply). In this case, the supply curve gives increasing real output as a function of the price level. An ‘adverse’ shift of this curve would be a shift up. It would not affect real output in the liquidity trap since the aggregate demand curve is vertical. it would not impose any costs as the increased price level would reduce the real money supply from plenty of liquidity to still plenty of liquidity. This model of aggregate supply is no good (it doesn’t fit the facts). It is easy to fear that Krugman implicitly assumed it was valid when in a rush (at least this is easy if one hasn’t been reading Krugman every day for years–he doesn’t do things like that).

  2. A fixed expectations-unaugmented Phillips curve which gives inflation as an increasing function of output. An ‘adverse’ shift of he Phillips curve would imply higher inflation. This would have no costs.

  3. An expectations-augmented Phillips curve in which expected inflation is equal to lagged inflation–output becomes a function of the change in inflation. In a liquidity trap, there would be either accelerating inflation or accelerating deflation. For a fixed money supply accelerating inflation would reduce real balances until the economy would no longer be in a liquidity trap. The simple model would imply the possibility of accelerating deflation and ever decreasing output. This model is no good, because such a catastrophe has never occurred, Japan had constant mild deflation which did not accelerate, even during the great depression the periods of deflation ended.

  4. An expectations augmented Phillips curve with rational expectations–oh hell I’ll just assume perfect foresight. Here both the aggregate demand and aggregate supply curves are vertical. If they are at different levels of output, there is no solution. The result is that a liquidity trap is impossible. This is basically a flexible price model. If there were aggregate demand greater than the fixed aggregate supply, the price level would jump up until the real value of money wasn’t enough to satiate liquidity preference. Krugman assumed that, in the long run, people don’t make systematic forecasting mistakes. So he assumed that the economy can’t stay in the liquidity trap for the long run. Ah yes, his model had everything new classical in the long run (this is the point on which Krugman has marked his beliefs to market).

The argument that Krugman would not have reached his conclusions about the economics of economies in liquidity traps if he had considered the supply side only makes sense if it includes the intermediate step that, if one considers the supply side, one must conclude that economies can never be in liquidity traps. This is no good as Japan was in the liquidity trap as are all developed countries at present.

I think the only promising effort here was (3)–a Phillips curve with autoregressive expectations. The problem is: why hasn’t accelerating deflation ever occurred? Way back in 1999, Krugman clearly thought that the answer was just that we had been lucky so far. He warned of the risk of accelerating deflation. Now he thinks he was wrong. Like Krugman, I think the reason is that there is downward nominal rigidity — that it is very hard to get people to accept a lower nominal wage or sell for a lower price. This depends on the change in the wage or price and not in that change minus expected inflation.

Clearly this rigidity isn’t absolute (Japan has had deflation and there were episodes of deflation in the 30s). But it is possible to get write a model in which unemployment is above the non accelerating inflation rate, but nominal wages aren’t cut. In this case expected inflation remains constant–actual deflation doesn’t occur so expected deflation doesn’t occur. The math can work. See here.

Must-read: Tim Duy: “Yellen Pivots Toward Saving Her Legacy”

Must-Read: Ever since the Taper Tantrum, it has seemed to me that the center of gravity of the FOMC has not had a… realistic picture of the true forward fan of possible scenarios.

Now Tim Duy sees signs that the center of the FOMC’s distribution is moving closer to mine. Of course, I still do not see the FOMC taking proper account of the asymmetries, but at least their forecast of central tendencies no longer seems as far awry to me as it had between the Taper Tantrum and, well, last month:

Tim Duy: Yellen Pivots Toward Saving Her Legacy: “Janet Yellen… [would] her legacy… amount to being just another central banker…

…who failed miserably in their efforts to raise interest rates back into positive territory[?] The Federal Reserve was set to follow in the footsteps of the Bank of Japan and the Riksbank, seemingly oblivious to their errors. In September… a confident Yellen declared the Fed would be different…. ANN SAPHIR…. “Are you worried… that you may never escape from this zero lower bound situation?” CHAIR YELLEN…. “I would be very surprised if that’s the case. That is not the way I see the outlook or the way the Committee sees the outlook…. That’s an extreme downside risk that in no way is near the center of my outlook.”…

Bottom Line: Rising risks to the outlook placed Yellen’s legacy in danger. If the first rate hike wasn’t a mistake, certainly follow up hikes would be. And there is no room to run; if you want to ‘normalize’ policy, Yellen needs to ensure that rates rise well above zero before the next recession hits. The incoming data suggests that means the economy needs to run hotter for longer if the Fed wants to leave the zero bound behind. Yellen is getting that message. But perhaps more than anything, the risk of deteriorating inflation expectations – the basis for the Fed’s credibility on its inflation target – signaled to Yellen that rates hike need to be put on hold. Continue to watch those survey-based measures; they could be key for the timing of the next rate hike.