Believe those who are seeking the truth. Doubt those who find it. Andre Gide

Monday, February 18, 2019

Is Neo-Fisherism Nuts?

According to my friend and former colleague Steve Williamson, inflation is low in Japan because of the Bank of Japan's policy of keeping its policy rate low. Accordingly, if the BOJ wants to hit its 2% inflation target, it should raise its policy rate and keep it persistently higher. This is what I've called the NeoFisherian proposition. It's a provocative idea because it flies in the face of conventional wisdom. But is it correct? Does it serve as a practical guide for monetary policy? My feeling is that the answers to these questions are "no" and "no." In what follows, I explain why.

At some point in their undergraduate career, students of macroeconomics are introduced to the Fisher equation. The Fisher equation usually stated as R = r + π or, in words:

Nominal Rate of Interest = Real Rate of Interest + Expected Rate of Inflation

For simplicity, think of the real rate of interest as the rate of return an investor can achieve by storing goods across time. For squirrels storing nuts, the real rate of interest is negative. For humans planting corn, it is positive. Whatever its value, let's just fix it at some number and assume it remains invariant over time (this is not a critical assumption for the arguments I want to develop below). Then, the Fisher hypothesis is that the nominal rate of interest should move one-for-one with the expected rate of inflation.

How does the Fisher equation hold up in the data? Let's just say that the evidence is mixed. Fisher himself famously rejected it as being empirically relevant. But over long periods of time, and also across countries, various nominal interest rates do appear positively correlated with the measured inflation rate (taken as a proxy for expected inflation).

Well, correlation is one thing, explanation is another. What is the theoretical underpinning of the Fisher equation? One way to view it is as a no-arbitrage-condition. Suppose that planting a bushel of corn yields 1.02 bushels at harvest (2% real rate of interest). Suppose that the nominal price of corn (its price measured in dollars) is expected to rise 10% by harvest time. What rate of return would an investor demand of a bond promising to deliver money at harvest time? The Fisher equation says that the investor should demand a rate of return of at least 12%. The bond would then deliver 12% more dollars that, if spent on corn at harvest, would leave an inflation-adjusted return of 2%. In this case, the investor would be just indifferent between investing in a corn planting venture and the nominal security.

Viewed in this light, the Fisher equation can be interpreted as the interest rate bond-holders demand, given their outlook on inflation. And, indeed, the standard textbook explanation for why nominal interest rates tend to rise with inflation provides a clear causal link, starting with monetary policy in the form of base-money growth rate:

    [1] increase in money supply growth (spent on goods or delivered as tax cuts or transfers);
    [2] causes increase in demand, which causes prices to rise;
    [3] inflation expectations adjust upwards accordingly;
    [4] bondholders demand higher interest rate to compensate for higher expected inflation.

The interpretation above assumes that monetary policy does not target the interest rate on bonds. Instead, it grows the money supply and lets the market determine the nominal interest rate. But note that monetary policy is targeting an interest rate in this explanation. In particular, the nominal interest rate on central bank money (reserves and currency) is set to zero. This policy goes by the acronym ZIRP (zero-interest-rate-policy). Moreover, there is a Fisher equation that holds for money. It looks like this R_m + LP = r + π, or in words:

Nominal interest rate on money + Liquidity premium = Real interest rate + Expected inflation 

If the nominal interest rate on money is zero, then money must be held for its non-pecuniary benefits (liquidity). The liquidity premium on money is in this case equal to the nominal interest rate on an illiquid bond; i.e., LP = R = r + π. 

Now, if the nominal security yielding a positive interest rate in the story above consists of government bonds (denominated in the domestic currency), then the only way to explain the apparent discount on government bonds is by appealing to an explicit government policy that renders these bonds illiquid relative to central bank money. And indeed, we see restrictions like this in place throughout history. For example, convenient low-denomination zero-interest notes (cash)  versus inconvenient large-denomination notes (bonds) trading at discount. Or consider today, where interest-bearing accounts at the U.S. Treasury are deliberately rendered useless for making payments. Or the Fed's apparent aversion to setting up a repo facility for U.S. Treasury debt in order to enforce a ceiling on its interest rate target path (such a facility would serve to reduce the demand for reserves).

Monetary theorists like Neil Wallace have puzzled forever over the phenomenon of why government bonds should trade at a discount (the so-called, coexistence puzzle). Others, like former Minneapolis Fed president Narayana Kocherlakota, have attempted to rationalize policies that render government bonds illiquid; see here. At the end of the day what is true is the following: the nominal interest rate on government bonds is, one way or another, a deliberate policy choice (for governments that issue debt denominated in the money they issue). This goes for default risk as well. There is no reason to default on debt that constitutes a promise to deliver money that one can costlessly produce. If default takes place in such circumstances, it is a policy choice, not an economic necessity.

Alright, what does all this have to do with Neo-Fisherism and the Neo-Fisherian proposition? I hope everything will fall together in due course. In the meantime, let's assume that the Fisher equation is sound theoretically and holds approximately well in the data. Would this support the proposition? It's clearly not enough because the proposition has to do with causality. The conventional view outlined above is also consistent with theory and evidence. Moreover, the conventional view as expressed through [1]-[4] provides a simple, coherent, easy-to-understand story for why we'd expect to see a positive correlation between interest rates and inflation in the data. It may not be correct, but at least it's understandable. Can the Neo-Fisherian proposition be explained in a similarly simple and compelling way? I think it's important for ideas to expressed in clear and simple terms. If policymakers are going to take the proposition seriously, the underlying economic mechanisms will have to be explained in a simple and straightforward manner. It will have to resonate with listeners at some level.

I've only heard of one mechanism that I find semi-plausible: the idea that a higher policy rate increases the interest expense of government debt which, if not met with a tax increase, must be met by an acceleration in money/bond printing (some empirical evidence here). Alternatively, could it be that an increase in the policy rate serves as a type of cost-push shock that propagates itself forward through some adaptive inflation expectations mechanism? I don't know, but it seems worth exploring.

But this is not how Neo-Fisherians explain the mechanism. You can listen to Steve explaining the mechanism in this David Beckworth podcast beginning at the 21 minute mark. There is also this piece published in the St. Louis Fed's Regional Economist: Neo-Fisherism: A Radical Idea or the Most Obvious Solution to the Low-Inflation Problem? Here is how he explains it (boldfont text representing my emphasis):
But, what if we turn this idea on its head, and we think of the causation running from the nominal interest rate targeted by the central bank to inflationThis, basically, is what Neo-Fisherism is all about [...] But how would this work? [...] To simplify, think of a world in which there is perfect certainty and where everyone knows what future inflation will be. Then, the nominal interest rate R can be expressed as R = r + π, where r is the real (inflation-adjusted) rate of interest and π is future inflation. 
Then, suppose that the central bank increases the nominal interest rate R by raising its nominal interest rate target by 1 percent and uses its tools (intervention in financial markets) to sustain this forever. What happens? [...] after a long period of time, the increase in the nominal interest rate will have no effect on r and will be reflected only in a one-for-one increase in the inflation rate, π. In other words, in the long run, the only effect of the nominal interest rate on inflation comes through the Fisher effect; so, if the nominal interest rate went up by 1 percent, so should the inflation rate—in the long run.
First, I wonder  what "tools and interventions" he has in mind. If the tool involves a sustained increase in the money growth rate, then there's nothing new here--this would just be standard Monetarist reasoning consistent with the textbook explanation [1]-[4] above.

But I think he means something else. As I explained above, the "Fisher effect" is a statement about how expected inflation affects the interest rate, not the other way around. The interest rate in Steve's thought experiment is fixed. Therefore, the "Fisher effect" here must relate to the economic force that causes inflation expectations to rise. What is this force? He doesn't say. One is left with the feeling that, well, since the Fisher equation holds in theory (and to Steve, in the data as well), inflation expectations somehow must adjust to make this true. Ergo, raising the interest rate will eventually lead to an increase in inflation. Central bankers need more than this to go on. In any case, I think that the logic is flawed. Let me explain.

How Neo-Fisherism Leads to Bad Monetary Policy Advice 

Let's take the case of Japan. Japan's inflation rate has been close to zero for a long time. Although I do not know why, Japan wants a higher inflation rate. How is to achieve this objective? 
I laid out my case here: The Failure to Inflate Japan. In a nutshell, the argument is this. [1] Peg the policy rate to zero all along the maturity structure of government debt (the BOJ is doing this); [2] Grow the nominal debt more rapidly until the desired inflation occurs (the government is not doing this). 
Steve roundly rejects my line of reasoning--which is, of course, fine--except that (my apologies, but) I don't understand what he's saying (see here):
(i) How does the CB keep R=0 "along the yield curve." How could you have a flat yield curve at zero with positive inflation? (ii) If you're eliminating all taxes and the fiscal authority is financing everything by issuing debt, and the CB is trying to sustain R=0, then something has to give. For example, people start anticipating that fiscal authority can't roll over the debt, default premia rise on the government debt, and CB is forced to increase R to generate the CB profits required to keep the government afloat.
To answer (i), I think the BOJ has shown how it can be done. If the market is discounting JGBs, the BOJ can just buy (or threaten to buy) them up at par. To answer (ii), there is no nominal default risk to consider for Japan--at least, there's no economic reason to default: Japan can print the money it's  promising its bond holders. (And if one is worried about the real default implicit in inflation, remember that increasing the inflation rate is exactly the policy goal here.)

Steve has also pointed out that Japan's nominal debt has already grown substantially, so where's the inflation? The answer is that one cannot just look at supply--one must also consider demand. Evidently, the demand for JGBs has been increasing rapidly as well. If the supply had not accommodated this growing demand, Japan may very well have experienced the mother of all deflations (that demand is not observed and has to be inferred from price and quantity is a key weakness in this story).

Alright, so Steve does not like my way of increasing inflation. What does he recommend as an alternative? The BOJ should raise its policy rate, say from 0 to 400bp, and keep it there. There may be a short-run "liquidity effect," but the inflation will eventually come. How do we know? The Fisher equation. Can you elaborate? The Fisher effect will mean that inflation expectations will rise and inflation will follow. Why should inflation expectations rise? Because ... well, rational expectations ... and the Fisher equation. Can you elaborate? (Rinse and repeat.)

In any case, even if one accepts "rational expectations," the argument is not correct. As I explained above, there are really two Fisher equations:

[Fisher 1]: R = r + π
[Fisher 2]: R_m + LP = r + π

where, in case you forgot, r is real interest rate, π is expected inflation, R is nominal rate on illiquid bond, R_m is nominal rate on liquid bond (including reserves) and LP is a liquidity premium.

The interest rate controlled directly by the central bank is R_m. The central bank can easily set R_m = 0 and then monetize all the tax-cuts that are necessary to increase π. As π increases, so will R, in accordance with the Fisher equation. Could it be that Neo-Fisherians are confusing R with R_m? (This seems unlikely as I know that Steve knows the difference.)

What then is the effect of raising R_m? Well, it's complicated. Much depends on the structure of fiscal policy (Ricardian vs. Non-Ricardian); see here. In some models, raising R_m leaves r and π unchanged, which implies that the liquidity premium on government money LP falls. Eliminating the liquidity premium on government money/bonds is the famous Friedman rule prescription (convention version sets R_m = 0 and π = -r, but R_m = r + π for any π > 0 also works). But in other models, increasing R_m puts upward pressure on the real rate of interest, reducing the demand for investment, leading to economic contraction with no change in long-run inflation; see here.

The point of all this is, IF higher inflation is desired (and I am by no means advocating any such policy), THEN why not keep the policy rate low and use "free lunch" fiscal policies as long as inflation remains below target? Why bother experimenting with the Neo-Fisherian prescription of raising the policy rate that's somehow supposed to make people magically expect higher inflation?

Friday, January 11, 2019

When is more competition bad?

Contrary to popular belief, standard economic theory does not provide a theoretical foundation for the notion that "competition is everywhere and always good." It turns out that legislation that promotes competition among producers may improve consumer welfare. Or it may not. As so many things in economics (and in life), it all depends.

I recently came across an interesting paper demonstrating this idea by Ben Lester, Ali Shourideh, Venky Venkateswaran, and Ariel Zetlin-Jones with the title "Screening and Adverse Selection in Frictional Markets," forthcoming in the Journal of Political Economy.The paper is written in the standard trade language. Like any trade language, it's difficult to understand if you're not in the trade! But I thought the idea sufficiently important that I asked Ben to translate the basic results and findings for a lay audience. I'm glad to say he was very happy to oblige.

And so, without further ado, today's guest post by Ben Lester, my colleague at the Philadelphia Fed.
You can follow Ben on Twitter :  @benjamminlester 

Competition in Markets with Asymmetric Information
By Benjamin Lester

In many basic economic models, competition is good – it increases welfare.  As a result, policy makers often introduce reforms that they hope will reduce barriers or “frictions” in order to increase competition.  For example, the Dodd-Frank Act contains regulations aimed at promoting more competition in certain financial markets, such as derivatives and swaps, while the Affordable Care Act contained provisions that were intended to promote competition across health insurance providers.

In a recent paper with Ali Shourideh, Venky Venkateswaran, and Ariel Zetlin-Jones, we re-examine the question of whether more competition is welfare-improving in markets with a particular feature – what economists call “asymmetric information.”  These are markets where one side has information that is relevant for a potential trade, but the other side can’t see it. Classic examples include insurance markets, where an individual knows more about his own health than an insurer; loan markets, where a borrower knows more about her ability to repay than a lender; and financial markets, where the owner of an asset (like a mortgage-backed security) may know more about the value of the underlying assets than a potential buyer.

Unfortunately, understanding the effects of more or less competition in markets with asymmetric information has been constrained by a shortage of appropriate theoretical frameworks.  As Chiappori et al. (2006) put it, there is a “crying need for [a model] devoted to the interaction between imperfect competition and adverse selection.”

What we do
We develop a mathematical model of a market – to fix ideas, let’s call it an insurance market – that has three key ingredients.  The first ingredient is adverse selection: one side of the market (consumers) know more about their health than the other side of the market (insurers).  Second, we allow the two sides of the market to trade sophisticated contracts: as in the real world, insurers can offer consumers a rich set of options to choose from, consisting of different levels of coverage that can be purchased at different prices.  Last, we introduce imperfect competition by assuming that consumers don’t always have access to multiple insurers: in particular, each consumer will get offers from multiple insurers with some probability, but there is also a chance of receiving only one offer.[1]  Hence, our model allows us to capture the case of perfect competition (where all consumers get multiple offers), monopoly (where all consumers get only one offer), and everything in between.

What we find

One of our main results is that increasing competition can actually make people worse off.[2]  To understand why, it’s important to understand the types of contracts that our model predicts will be offered by insurers.  Let’s say that there are two types of consumers: those who are likely to require large medical expenses (“sick” consumers), and those who are not (“healthy” consumers).  Then insurers will often find it optimal to offer two different plans: one that is expensive but provides more coverage, and one that is cheaper but provides less coverage.[3]  Designed correctly, these two options will induce consumers to self-select into the plan intended for them, so that sick consumers will pay a higher price for more coverage and healthy consumers will pay a lower price for less coverage.

An important property of these contracts is that they fully insure sick consumers, but they under-insure healthy consumers.  Ideally, insurers would like to offer healthy patients more coverage, but they can’t: given the lower price, sick consumers would choose this new plan, making it no longer profitable for insurers to offer it.  This theoretical result – that separating the sick from the healthy requires under-insuring healthy consumers – is a fundamental result in markets where asymmetric information is present.  The relevant question for us is: how does the amount of competition determine the extent to which healthy consumers are under-insured? The answer we find is that some competition can induce insurers to provide healthy consumers with more insurance, but too much competition can have the opposite effect. 

The intuition is as follows.  When consumers are more likely to receive multiple offers, insurers respond by making more attractive offers to consumers, as they try to retain market share.  The key question turns out to be: does increasing competition make them sweeten the deal more for sick consumers, or for healthy consumers? On the one hand, as the offer intended for sick consumers gets better, they have less incentive to take the offer intended for healthy consumers – in the parlance of economics, their “incentive constraint” loosens.  Hence, as insurers sweeten the offer intended for sick consumers, they are able to offer healthy consumers more coverage, and welfare rises.[4]  On the other hand, however, as the offer intended for healthy consumers become more attractive, sick consumers are more tempted to take it – their incentive constraint tightens – and the only way to keep the two separate is to reduce the amount of coverage being offered to healthy consumers, causing welfare to decline.

In the paper, we show that the former, positive effect dominates in markets where insurers have a lot of market power, while the latter, negative effect dominates when the market is relatively competitive. Hence, in markets with asymmetric information, welfare is maximized at some interior point, where there is some competition, but not too much!

Other results and future research
In the paper, we also show that increasing transparency has ambiguous effects on welfare.  In particular, we study the effects of a noisy signal about a consumer’s type – in the insurance example, this could be a blood test or information about an individual’s pre-existing conditions.  We show that increasing transparency is typically beneficial when insurers have a lot of market power, but it can be detrimental to welfare in highly competitive environments.

More generally, our model provides a tractable framework to confront a variety of theoretical questions regarding markets that suffer from asymmetric information, and offers a number of insights into existing empirical studies, too.[5]  For example, there is a large literature that tests for the presence of asymmetric information by studying the quantitative relationship between, e.g., the amount of insurance that consumers buy and their tendency to get sick.[6]  However, according to our analysis, insurers find it optimal to offer menus that separate consumers only when markets are sufficiently competitive, and when there is a sufficiently large number of sick consumers in the population.  Otherwise, they find it best to offer a single insurance plan.  This finding implies that, when insurers have sufficient market power, there will be no relationship between the quantity of insurance a consumer buys and his health status.  In other words, one can’t empirically test for asymmetric information without controlling for the market structure.  This is just one of many positive predictions of our model that we plan to test in the data.

Burdett, K., and K. L. Judd (1983) “Equilibrium Price Dispersion,” Econometrica, 51, pages 955–69.
Chiappori, P.-A., B. Jullien, B. Salanié, and F. Salanié (2006) “Asymmetric Information in Insurance: General Testable Implications,” RAND Journal of Economics, 37, pages 783–98.
Chiappori, P.-A., and B. Salanié  (2000) “Testing for Asymmetric Information in Insurance Markets” Journal of Political Economy,  108, pages 56–78.
Lester, B., A. Shourideh, V. Venkateswaran, and A. Zetlin-Jones (2018) “Screening and Adverse Selection in Frictional Markets,” Journal of Political Economy, forthcoming.

[1] We borrow this modeling device from the paper by Burdett and Judd (1983).
[2] At a high level, the idea that reducing frictions can sometimes make people worse off is not unique to our paper; these types of results are known from the theory of the second best. What distinguishes our result is the context in which it arises, and our ability to characterize precisely when and why reducing frictions (or increasing competition) is harmful.
[3] The negative relationship between price and coverage should be familiar to most readers; see, e.g., the metal tiers (platinum, gold, silver, bronze) offered at
[4] Since sick consumers are always fully insured, consumers’ welfare always rises when healthy consumers are offered more insurance.  On a more technical level, all of our statements about welfare are based on a measure of ex ante, utilitarian welfare.
[5] As a technical aside, unlike many models of asymmetric information and screening, we find that an equilibrium always exists in our environment, that the equilibrium is unique, and that the equilibrium does not rely on any assumptions regarding “off-path beliefs.”
[6] See the seminal paper by Chiappori and Selanie (2000).


The views expressed here are those of the authors and do not necessarily reflect the views of the Federal Reserve Bank of Philadelphia or the Federal Reserve System.