Global Imbalances

I gave some comments on “Global Imbalances and Currency Wars at the ZLB,” by Ricardo J. Caballero, Emmanuel Farhi, and Pierre-Olivier Gourinchas at the conference, “International Monetary Stability: Past, Present and Future”, Hoover Institution, May 5 2016. My comments are here, the paper is here 

The paper is a very clever and detailed model of "Global Imbalances," "Safe asset shortages" and the zero bound. A country's inability to "produce safe assets" spills, at the zero bound, across to output fluctuations around the world. I disagree with just about everything, and outline an alternative world view.

A quick overview:

Why are interest rates so low? Pierre-Olivier & Co.: countries can't  “produce safe stores of value”
This is entirely a financial friction. Real investment opportunities are unchanged. Economies can’t “produce” enough pieces of paper. Me: Productivity is low, so marginal product of capital is low.

Why is growth so low? Pierre-Olivier: The Zero Lower Bound is a "tipping point." Above the ZLB, things are fine. Below ZLB, the extra saving from above drives output gaps. It's all gaps, demand. Me: Productivity is low, interest rates are low, so output and output growth are low.

Data: I Don't see a big change in dynamics at and before the ZLB. If anything, things are more stable now that central banks are stuck at zero. Too slow, but stable.  Gaps and unemployment are down. It's not "demand" anymore.


Exchange rates. Pierre-Olivier  "indeterminacy when at the ZLB” induces extra volatility. Central banks can try to "coordinate expectations." Me: FTPL gives determinacy, but volatility in exchange rates. There is no big difference at the ZLB.

Safe asset Shortages. Pierre-Olivier: driven by a large mass of infinitely risk averse agents. Risk premia are therefore just as high as in the crisis. Me: Risk premia seem low. And doesn't everyone complain about "reach for yield" and low risk premia?

Observation. These ingredients are plausible about fall 2008. But that's nearly 8 years ago! At some point we have to get past financial crisis theory to not-enough-growth theory.

But, finally, praise. This is a great paper. It clearly articulates a world view, and you can look at the assumptions and mechanisms and decide if you think they make sense. I am in awe that Pierre-Olivier & Co. were able to make a coherent model of these buzzwords.

But great theory is great theory. To a critic, the assumptions are necessary as well as sufficient. I  read it as a brilliant negative paper, almost a parody: Here are the extreme assumptions that it takes to justify all the policy blather about "savings gluts" "global imbalances" "safe asset shortages" and so on. To me, it shows just how empty the idea is, that our policy-makers understand any of this stuff at a scientific, empirically-tested level, and should take strong actions to offset the supposed problems these buzzwords allude to.

I hope this taste gets you to read  my comments and the paper. 

Central Bank Governance and Oversight Reform

The Hoover Institution Press just published "Central Bank Governance and Oversight Reform," the collected volume of papers, comments, and discussion from last May's conference here by the same name. You can get the  book or e-book here at the Hoover press or here at amazon.com. The individual chapter pdfs are available here.  Press release here.

(My modest contributions are in the preface and a discussion of Paul Tucker's Chapter 1. I agree it would be nice to have a more rule-based approach to lender of last resort and bailout functions, but wouldn't lots of equity so you don't have to mop up so often be even better?)

This is part of an emerging series of monetary policy conferences at Hoover. Tomorrow we will have a conference on international monetary policy. Stay tuned...

The blurb:

How can we balance the central bank’s authority, including independence, with accountability and constraints? Drawn from a 2015 Hoover Institution conference, this book features distinguished scholars and policy makers’ discussing this and other key questions about the Fed. Going beyond the simple decision of whether to raise interest rates, they focus on a deeper set of questions, including, among others, How should the Fed make decisions? How should the Fed govern its internal decision-making processes? What is the trade-off between greater Fed power and less Fed independence? And how should Congress, from which the Fed ultimately receives its authority, oversee the Fed?

The contributors discuss, for instance, whether central banks can both follow rule-based policy in normal times but then take a discretionary, do-what-it-takes approach to stopping financial crises. They evaluate legislation, recently proposed in the U.S. House and Senate, that would require the Fed to describe its monetary policy rule and, if and when the Fed changed or deviated from its rule, explain the reasons. And they discuss to best ways to structure a committee—like the Federal Open Market Committee, which sets interest rates—to make good decisions, as well as offer historical reflections on the governance of the Fed and much more. They conclude with an important reminder: how important it is to have a “healthy separation between government officials who are in charge of spending and those who are in charge of printing money,” the most essential part of good governance.

The contents:

Preface
By John H. Cochrane and John B. Taylor

Chapter 1: How Can Central Banks Deliver Credible Commitment and Be “Emergency Institutions”?
By Paul Tucker

Chapter 2: Policy Rule Legislation in Practice
By David H. Papell, Alex Nikolsko-Rzhevskyy and Ruxandra Prodan

Chapter 3: Goals versus Rules as Central Bank Performance Measures
By Carl E. Walsh

Chapter 4: Institutional Design: Deliberations, Decisions, and Committee Dynamics
By Kevin M. Warsh

Chapter 5: Some Historical Reflections on the Governance of the Federal Reserve
By Michael D. Bordo

Chapter 6: Panel on Independence, Accountability, and Transparency in Central Bank Governance
By Charles I. Plosser, George P. Shultz, and John C. Williams

Macro Musing Podcast

I did a podcast with David Beckworth, in his "macro musings" series, on the Fiscal Theory of the Price Level, blogging, and a few other things.



(you should see the link above, if not click here to return to the original).

You can also get the podcast at Sound Cloud, along with all the other ones he has done so far, or on itunes here.  For more information, see David's post on the podcast.

Neo-Fisherian caveats

Raise interest rates to raise inflation? Lower interest rates to lower inflation? It's not that simple.

A correspondent from an emerging market wrote enthusiastically. His country has somewhat too high inflation, currency depreciation and slightly negative real rates. A discussion is going on about raising rates to combat inflation. Do I think that lowering rates in this circumstance is instead the way to go about it?

As you can tell, posing the question this way makes me very uncomfortable! So, thinking out loud, why might one pause at jumping this far, this fast?

Fiscal policy.  Fiscal policy deeply underlies monetary policy. In my own "Fisherian" explorations, the fiscal theory of price level is a deep foundation. If the government is printing up money to pay its bills, the central bank can do what it wants with interest rates, inflation is coming anyway.


Conversely, underlying the decline in inflation in the US, Europe, and Japan is an extraordinary demand for nominal government debt.

Bond markets seem to think we'll pay it off. And that is not too terribly an irrational expectation. Sovereign debts are self-inflicted wounds. A little structural reform to get growing again, tweaks to social security and medicare, and next thing you know we're back in the 1990s and wondering what to do when all the government bonds are paid off. Also, valuation is more about discount rates than cashflows. People seem happy -- for now -- to hold government debt despite unusually low prospective returns.

My correspondent answers that his country is actually doing well fiscally.  However, his country is also a bit low on reserves and having exchange rate and capital flight problems.

But current deficits are not that important to inflation either in theory or in fact. The fiscal policy that matters is expectations of very long term stability, not just a few years of surpluses. Also, contingent liabilities matter a lot. If investors in government debt see a government that will bail out all and sundry in the next downturn, or faces political risks, even temporary surpluses are not an assurance to investors.  (Craig Burnside, Marty Eichenbaum and Sergio Rebelo's "Prospective Deficits and the Asian Currency Crises, in the JPE and ungated here is a brilliant paper on this point.)

Rational expectations. The Fisherian proposition also relies deeply on rational expectations. In the simplest version, \( i_t = r + E_t \pi_{t+1} \), people see nominal interest rates rise, they expect inflation to be higher, so they raise their prices. As a result of that expectation inflation is, on average, higher. (Loose story alert.)

How do they expect such a thing? Well,  rational expectations is sensible when there is a long history in one regime. People see higher interest rates, they remember times of high interest rates in the past, like the late 1970s, so they ratchet up their inflation expectations. Or, people see higher interest rates, and they've gotten used to the Fed raising interest rates when the Fed sees inflation coming, so they raise their expectations. The motto of rational expectations is "you can't fool all of the people all of the time," not "you can never fool anyone," nor "people are clairvoyant."

The Fisherian prediction relies on the interest rate change to be credible, long-lasting, and to lead to the right expectations. A one-off experiment, that might be read as cover for a dovish desire to boost growth at the expense of more inflation, and that might be quickly reversed doesn't really map to the equations. Europe and Japan, stuck at the zero bound, with a fiscal bonanza (low interest costs on the debt) and slowly decreasing inflation expectations is much more consistent with those equations.

Liquidity. When interest rates are positive and money does not pay interest, lowering rates means more money in the system, and potentially more lending too. This classic liquidity channel, which goes the other way, is absent for the US, UK, Japan and Europe, since we're at the zero bound and since reserves pay interest.  (Granted, I couldn't get the equations of the liquidity effect to be large enough to offset the Fisher effect, but that depends on the particulars of a model. )

Successful disinflations. Disinflations are a combination of fiscal policy, monetary policy, expectations, and liquidity. Tom Sargent's classic ends of four hyperinflations tells the story beautifully.

Large inflations result from intractable fiscal problems, not central bank stupidity. In Tom's examples, the government solves the fiscal problem; not just immediately, but credibly solves it for the forseeable future. For example, the German government in the 1920s faced enormous reparations payments. Renegotiating these payments fixed the underlying fiscal problem. When the long-term fiscal problem was fixed, inflation stopped immediately. Since everybody knew what the fiscal problem was, expectations were quickly rational.

The end of inflation coincided with a large money expansion and a steep reduction in nominal interest rates. During a time of high inflation, people use as little money as possible. With inflation over, real money demand expands.  There was no period of monetary stringency or interest-rate raising preceding these disinflations.

So these are great examples in which the Fisher story works well -- lower interest rates correspond to lower inflation, immediately. But you can see that lower interest rates are not the whole story. The central bank of Germany 1922 could not have stopped inflation on its own by lowering rates.  I suspect the same is true of high inflation countries today -- usually something is wrong other than just the history of interest rates.

So, apply new theories with caution!

To the raising interest rates question for the US and Europe, some of the same considerations apply. We won't have any liquidity effects, as central banks are planning to just pay more interest on abundant reserves. Higher real interest rates will raise fiscal interest costs, which is an inflationary shock by fiscal theory considerations. The big question is expectations. Will people read higher interest rates as a warning of inflation about to break out, or as a sign that inflation will be even lower?

The Habit Habit

The Habit Habit. This is an essay expanding slightly on a talk I gave at the University of Melbourne's excellent "Finance Down Under" conference. The slides

(Note: This post uses mathjax for equations and has embedded graphs. Some places that pick up the post don't show these elements. If you can't see them or links come back to the original. Two shift-refreshes seem to cure Safari showing "math processing error".)

Habit past: I start with a quick review of the habit model. I highlight some successes as well as areas where the model needs improvement, that I think would be productive to address.

Habit present: I survey of many current parallel approaches including long run risks, idiosyncratic risks, heterogenous preferences, rare disasters, probability mistakes -- both behavioral and from ambiguity aversion -- and debt or institutional finance. I stress how all these approaches produce quite similar results and mechanisms. They all introduce a business-cycle state variable into the discount factor, so they all give rise to more risk aversion in bad times. The habit model, though less popular than some alternatives, is at least still a contender, and more parsimonious in many ways,

Habits future: I speculate with some simple models that time-varying risk premiums as captured by the habit model can produce a theory of risk-averse recessions, produced by varying risk aversion and precautionary saving, as an alternative to  Keynesian flow constraints or new Keynesian intertemporal substitution. People stopped consuming and investing in 2008 because they were scared to death, not because they wanted less consumption today in return for more consumption tomorrow.

Throughout, the essay focuses on challenges for future research, in many cases that seem like low hanging fruit. PhD students seeking advice on thesis topics: I'll tell you to read this. It also may be useful to colleagues as a teaching note on macro-asset pricing models. (Note, the parallel sections of my coursera class "Asset Pricing" cover some of the same material.)

I'll tempt you with one little exercise taken from late in the essay.


A representative consumer with a fixed habit \(x\) lives in a permanent income economy, with endowment \(e_0\) at time 0 and random endowment \(e_1\) at time 1. With a discount factor \(\beta=R^f=1\), the problem is

\[ \max\frac{(c_{0}-x)^{1-\gamma}}{1-\gamma}+E\left[ \frac {(c_{1}-x)^{1-\gamma}}{1-\gamma}\right] \] \[ c_{1} = e_{0}-c_{0} +e_{1} \] \[ e_{1} =\left\{ e_{h},e_{l}\right\} \; pr(e_{l})=\pi. \] The solution results from the first order condition \[ \left( c_{0}-x\right) ^{-\gamma}=E\left[ (c_{1}-x)^{-\gamma}\right] \] i.e., \[ \left( c_{0}-x\right) ^{-\gamma}=\pi(e_{0}-c_{0}+e_{l}-x)^{-\gamma}% +(1-\pi)(e_{0}-c_{0}+e_{h}-x)^{-\gamma}% \] I solve this equation numerically for \(c_{0}\).

The first picture shows consumption \(c_0\) as a function of first period endowment \(e_0\) for \(e_{h}=2\), \(e_{l}=0.9\), \(x=1\), \(\gamma=2\) and \(\pi=1/100\).

The case that one state is a rare disaster is not special. In a general case, the consumer starts to focus more and more on the worst-possible state as risk aversion rises. Therefore, the model with any other distribution and the same worst-possible state looks much like this one.

Watch the blue \(c_0\) line first. Starting from the right, when first-period endowment \(e_{0}\) is abundant, the consumer follows standard permanent income advice. The slope of the line connecting initial endowment \(e_{0}\) to consumption \(c_{0}\) is about 1/2, as the consumer splits his large endowment \(e_{0}\) between period 0 and the single additional period 1.

As endowment \(e_{0}\) declines, however, this behavior changes. For very low endowments \(e_{0}\approx 1\) relative to the nearly certain better future \(e_{h}=2\), the permanent income consumer would borrow to finance consumption in period 0. The habit consumer reduces consumption instead. As endowment \(e_{0}\) declines towards \(x=1\), the marginal propensity to consume becomes nearly one. The consumer reduces consumption one for one with income.

The next graph presents marginal utility times probability, \(u^{\prime}(c_{0})=(c_{0}-x)^{-\gamma}\), and \(\pi_{i}u^{\prime}(c_{i})=\pi _{i}(c_{i}-x)^{-\gamma},i=h,l\). By the first order condition, the former is equal to the sum of the latter two. \ But which state of the world is the more important consideration? When consumption is abundant in both periods on the right side of the graph, marginal utility \(u^{\prime}(c_{0})\) is almost entirely equated to marginal utility in the 99 times more likely good state \((1-\pi)u^{\prime}(c_{h})\). So, the consumer basically ignores the bad state and acts like a perfect foresight or permanent-income intertemporal-substitution consumer, considering consumption today vs. consumption in the good state.

In bad times, however, on the left side of the graph, if the consumer thinks about leaving very little for the future, or even borrowing, consumption in the unlikely bad state approaches the habit. Now the marginal utility of the bad state starts to skyrocket compared to that of the good state. The consumer must leave some positive amount saved so that the bad state does not turn disastrous -- even though he has a 99% chance of doubling his income in the next period (\(e_{h}=2\), \(e_{0}=1\)). Marginal utility at time 0, \(u^{\prime }(c_{0})\) now tracks \(\pi_{l}u^{\prime}(c_{l})\) almost perfectly.

In these graphs, then, we see behavior that motivates and is captured by many different kinds of models:

1. Consumption moves more with income in bad times.

This behavior is familiar from buffer-stock models, in which agents wish to smooth intertemporally, but can't borrow when wealth is low....

2. In bad times, consumers start to pay inordinate attention to rare bad states of nature.

This behavior is similar to time-varying rare disaster probability models, behavioral models, or to minimax ambiguity aversion models. At low values of consumption, the consumer's entire behavior \(c_{0}\) is driven by the tradeoff between consumption today \(c_{0}\) and consumption in a state \(c_{l}\) that has a 1/100 probability of occurrence, ignoring the state with 99/100 probability.

This little habit model also gives a natural account of endogenous time-varying attention to rare events.

The point is not to argue that habit models persuasively dominate the others. The point is just that there seems to be a range of behavior that theorists intuit, and that many models capture.

When consumption falls close to habit, risk aversion rises, stock prices fall, so by Q theory investment falls. We nearly have a multiplier-accelerator, due to rising risk aversion in bad times: Consumption falls with mpc approaching one, and investment falls as well. The paper gives some hints about how that might work in a real model.