Winner of the New Statesman SPERI Prize in Political Economy 2016


Showing posts with label 2%. Show all posts
Showing posts with label 2%. Show all posts

Friday, 16 June 2017

Raising the inflation target

The argument for a higher inflation target is straightforward, once you understand two things. First the most effective and reliable monetary policy instrument is to influence the real interest rate in the economy, which is the nominal interest rate less expected inflation. Second nominal short term interest rates have a floor near zero (the Zero Lower Bound, or ZLB). Combine the two and you have a severe problem in a recession, because to combat the recession real interest rates need to move into negative territory, and how far they can go into that territory is limited by the ZLB. That means monetary policy alone may be unable to get us out of a recession.

Raising the inflation target reduces the likelihood that interest rates will hit the ZLB. To see why, note first that the long run (economists often say ‘equilibrium’ or ‘natural’) real interest rate is positive. Let’s say it is 2%. If the inflation target is 2%, and the ZLB is 0%, that would mean that in normal times the average nominal interest rate is 4% (2% inflation target + 2% to get to a 2% real interest rate). That means nominal interest rates can be cut by a maximum of 4% if the economy falters. That may be enough for a mild downturn, but as we saw in 2008 it is not enough for a major recession. However if the inflation target was 4%, nominal rates would now be able to fall by a maximum of 6%. That is probably enough to combat all but the worst kind of recession.

Why are many economists currently arguing that we should raise the inflation target from 2% to 4%? One of the reasons is that we now believe the long run real interest rate is currently lower than it was when the 2% target was first chosen. (This is sometimes referred to as secular stagnation.) If you go through the arithmetic above, you can see why a lower long run real interest rate will make the ZLB problem worse. The argument is that we now need to raise the inflation target to make sure we hit the ZLB less often in the future.

This issue moved from an academic discussion to a real possibility in the US a few days ago. When Fed Chair Janet Yellen had been asked about raising the inflation target in the past, she has tended to dismiss the idea. However she now says that it is something that the Fed will review in the future, and that it is one of the most important questions facing central bankers today.

This will undoubtedly give new impetus to the debate over whether the inflation target should be raised. We are in standard trade-off territory here. Economists generally agree a higher inflation target will in itself inflict greater costs on the economy, but they bring the benefit that the ZLB problem will occur less often. But there is an alternative, and clearly much better way out of this dilemma.

Governments have another instrument that has a reasonably predictable impact on aggregate demand, and which can be used to combat a recession: fiscal policy (changes to taxes and government spending). In the UK at the moment interest rates are at the ZLB in part because fiscal policy is contractionary (austerity). It would be far better to use this instrument to stimulate the economy in a recession than to raise the inflation target. Yet the institution of independent central banks have discouraged governments from using fiscal policy in this way.

It is no good central banks pretending that this is something which is up to governments, and that there is some unwritten law which means that central banks should keep quiet on such things. In reality, in both the UK and the Eurozone, the central bank actively encouraged governments to do the wrong thing with fiscal policy in the last recession. In other words, they encouraged austerity. If there is something inherent in the institution of a central bank that makes them give inappropriate advice in this way, then we should be asking how central banks can be changed as a matter of urgency.

What should happen in a recession, as soon as the central bank thinks that interest rates will hit the ZLB, is that central banks should say, out loud in public, that fiscal policy should become more expansionary. In addition central banks should say, out loud in public, that governments need not worry about rising debt and deficits due to the recession and any fiscal stimulus they undertake spooking markets because the central bank has that covered. Both statements have the merit of being true. 

Of course governments will need to restore debt to desired levels at some point, but that point should be well after interest rates have left the ZLB because then debt correction can be painless. The immediate aim of fiscal policy in a recession should be to allow interest rates to rise above the ZLB as soon as possible. That gives you the best macroeconomic outcome, and one that is far superior to raising the inflation target. The most important question facing central bankers today is why they failed to do that from 2009.

Now it is possible that, if democracy is in a bad shape (as it currently is in the US for example), the government may ignore the advice it receives from the central bank. In that case it is worth considering giving central banks some additional power to mimic a fiscal expansion, such as helicopter money for example. Or it may be worth considering institutional changes that allow nominal interest rates to go negative. Or raising the inflation target. But before doing any of those things we need to ensure that central banks give the right advice to governments when the next recession comes along.



Friday, 10 October 2014

Are DSGE models distorting policy? - a test case

The debate about the current state of academic macroeconomics continues, but it has reached a kind of equilibrium. Heterodox economists, some microeconomists and many others are actively hostile to the currently dominant macro methodology. Regardless, academic macroeconomists in the papers they write carry on using, almost exclusively, microfounded DSGE models. [1] Critics say this methodology was crucial in missing the financial crisis, but academic macroeconomists respond by highlighting all the work currently being done on financial frictions. I personally think missing the crisis was down to failings of a different kind, but that DSGE did hold back our ability to understand the impact of the crisis. However what I want to suggest here is a forward looking test.

Many of the difficult choices in conducting monetary (and sometimes fiscal) policy involve trade-offs between inflation and unemployment. We saw this in the UK particularly after the crisis, with inflation going well above target during the depth of the recession. What you do in those circumstances depends critically on the costs of excess inflation compared to the costs of higher unemployment. Is 1% higher unemployment worth more or less than 1% higher inflation to society as a whole?

What do New Keynesian DSGE models say about this trade-off? They do not normally model unemployment, but they do model the output gap, which we can relate to unemployment. Their answer is that inflation is much the more important variable, by a factor of ten or more. One reason they do this is that they implicitly assume the unemployed enjoy all the extra leisure time at their disposal. I have discussed other reasons here.

Empirical evidence, and frankly common sense, suggests this is the wrong answer. Thanks to the emergence of a literature that looks at empirical measures of wellbeing, we now have clear evidence that unemployment matters more than inflation. Sometimes, as in this study by Blanchflower et al, it matters much more. Another recent study by economists at the CEP shows that “life satisfaction of individuals is between two and eight times more sensitive to periods when the economy is shrinking than at times of growth”, which as well as being related to the unemployment/inflation trade-off raises additional issues around asymmetry.

So the DSGE models appear to be dead wrong. Furthermore the reasons why they are wrong are not deeply mysterious, and certainly not mysterious enough to make us question the evidence. For example prolonged spells of unemployment have well documented scarring effects (in part because employers cannot tell if unemployment was the result of bad luck or bad performance), which may even affect the children of the unemployed. So it is not as if economists cannot understand the empirical evidence.

Does that mean that the DSGE models are deeply flawed? No, it means they are much too simple. Does that mean that the work behind them (deriving social welfare functions from individual utility) is a waste of time? I would again say no. I have done a little work of this kind, and I understood some things much better by doing so. Will these models ever get close to the data? I do not know, but I think we will learn more interesting and useful things in the attempt. The microfoundations methodology is, in my view, a progressive research strategy.

So academics are right to carry on working with these models. But many academic macroeconomists go further than this. They argue that only microfounded DSGE models can provide a sound basis for policy advice. If you press them they will say that maybe it is OK for policymakers to use more ‘ad hoc’ models, but there is no place for these in the academic journals. In my view this is absolutely wrong for at least two reasons.

First, models that are clearly still at the early development stage should not be used to guide policy when we can clearly do better. In this particular case we can easily do better just by using ad hoc social welfare functions on top of an existing DSGE model. (The Lucas critique does not apply, which is why I like this example.) Yes these hybrid models will be ‘internally inconsistent’, but they are clearly better! Second, to confine academics to just doing development work on prototype experimental models is stupid: academic economists can have many useful things to say starting with aggregate models (as here, for example), and this is not something that policymakers alone have the resources (or sometimes the inclination) to do. (We also know that academics will give policy advice, whatever models they use!) Analysis using these more ad hoc but realistic models should be scrutinised in high quality academic journals.

Let’s be even more concrete. Take the debate over whether we should have a higher (than 2%) inflation target (or some other kind of target), because of the risks of hitting the zero lower bound. If this debate just involves micofounded DSGE models which clearly overweight inflation relative to unemployment, then these models will be guilty of distorting policy. This is not a matter of running some variants away from microfounded parameters (as in this comprehensive analysis, for example), but adopting realistic parameters as the base case. If this is not done, then microfounded DSGE models will be guilty of distorting this policy discussion.

[1] A few elderly bloggers, who use both DSGE and more ‘ad hoc’ models and think the critics have a point, are regarded by at least some academics as simply past their sell-by date.