What microeconomists think about macroeconomics
There
is a lot that is interesting in Diane Coyle’s 2012 Tanner lectures.
What I want to respond to here is an associated post,
where she expresses some of the frustrations that I know many microeconomists
have with macroeconomics. These can be summed up rather crudely as: why do we
disagree all the time, and yet appear so sure we are right, and don’t we
realise we are bringing the whole discipline into disrepute? Diane says that “macroeconomists
simply do not realise how low their stock has sunk in the eyes of their
microeconomist colleagues”. This
may
be an exaggeration, but who knows what is said when we are out of
earshot.
Because I (and pretty well all macroeconomists) do have great respect
for our microeconomic colleagues, we have some explaining to do.
(Jonathan Portes has
an excellent post
responding to some of the more specific comments Diane makes in this post.)
What I
want to say in summary is this. Microeconomists are right in many of their
criticisms, but what they often fail to see is the root cause of the problem.
This is that macroeconomic policy is highly political, with strong ideological
implications. Ideology and politics distort macroeconomics as a science. Yet
despite this, there is – and for many years has been – a substantial body of
analysis that most macroeconomics would sign up to, and which has
sound empirical backing.
What is
this substantial body of analysis? It is what used to be called the new neoclassical
synthesis (Goodfriend and King (1997) – see here
for more background and references). For a closed economy, its details are well
represented in Romer’s graduate textbook, for example. This body of analysis
has important gaps and omissions, of course, such as a naive and simplistic
view of the financial sector. However, as I argued recently,
the financial crisis itself showed up this incompleteness, but did not
invalidate most of what was in the synthesis. Indeed, events since the crisis have
provided significant empirical support for the Keynesian elements of that
synthesis. (Of course, there are caveats, some of which I have discussed in earlier posts,
and which I will return to below.)
So why
the appearance of constant disagreement among macroeconomists? The first point
to make is that the disagreement tends to focus on one part of the synthesis,
which is short term macroeconomic fluctuations: their causes and cures. This is
not the only part of the synthesis which has the potential for political and
ideological controversy, but it is where there is constant popular and media
interest. The second point, however, is that politics alone is not sufficient
to explain controversy within a scientific discipline. Here I might give
climate change is an example: despite strong pecuniary temptations, climate
change science is pretty united, and typically dissenting views come from outside
the discipline.
The
reason, I would suggest, why many macroeconomists do not sign up to the new
neoclassical synthesis is that its Keynesian component conflicts with an
ideological view which uses economics as part of its intellectual foundation. That
view is that markets generally work well when left free from political
interference and that government intervention is almost always bad. Now most microeconomists
will immediately point out that microeconomic theory as a whole does not
support this ideological view. Much microeconomic analysis is all about market
imperfections. But that misses the point. Those attracted to this ideological
position use a very partial take on economics for support, and are naturally
attracted to that part of the discipline.
Keynesian
analysis is all about the consequences of one particular market imperfection. Conventionally
this is seen as the externalities that arise from sticky prices. (I personally am
increasing drawn to describe them as the consequences of the existence of money,
but that is a different story.) It implies in general the need for constant
involvement of one arm of the state – the central bank – in stabilising the
economy, and in some circumstances the involvement of fiscal policy to do the same.
I have argued
that this analysis leaves those with the ideological view that free markets are
good and government intervention bad feeling very uncomfortable, so they will
try and find ways of avoiding and disputing this part of the synthesis.
Now
nothing I have said so far makes macroeconomics unique in attracting
ideologically driven controversy. There are areas of microeconomics which are
equally controversial for similar reasons. I would suggest the debate over
minimum wages is an example. An outsider looking at this debate might well
conclude that labour economists are as equally disputatious as macroeconomists on
this issue. Another example from my youth I always like to use is the ‘Cambridge
controversies’ over ‘reswitching’. This was a highly technical theoretical dispute,
but its ideological implications were such that views on this technical debate
were highly correlated with political beliefs.
I think
there is one factor that is peculiar to macroeconomics, and that is the role of
‘city’ economists. There are two elements here. One is that city economists
work in an environment which has a strong vested interest in promoting the free
market ideological view. The other is that part of the name of the game for
these guys is to differentiate the product. These are of course tendencies:
there are many excellent city economists who go with the evidence rather than
with ideological conviction.
Why is
it important to say all this? First, because the influence of ideology on
economics is not confined to macroeconomics. It is also not confined to the
political right, so there is no simple bias, but recognition rather than denial
is important. Second, the cure – if there is one – is evidence. As Jonathan
points out, the recent evidence is clearly with those who accept Keynesian
views, but I think there is an underlying problem. The way empirical evidence
is marshalled in the microfoundations methodology associated with DSGE
modelling makes it too easy
for those who hold ideologically based priors to retain and defend those priors,
which is one reason why I have tried
to suggest that it should not be the only way serious macroeconomic analysis is
done.
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