In an exasperated outburst, just before he
left the presidency of the European Central Bank, Jean-Claude Trichet
complained that, “as a policymaker during the crisis, I found the
available [economic and financial] models of limited help. In fact, I
would go further: in the face of the crisis, we felt abandoned by
conventional tools.”
Trichet went on to appeal for inspiration
from other disciplines – physics, engineering, psychology, and biology –
to help explain the phenomena he had experienced. It was a remarkable
cry for help, and a serious indictment of the economics profession, not
to mention all those extravagantly rewarded finance professors in
business schools from Harvard to Hyderabad.
So far, relatively little help has been
forthcoming from the engineers and physicists in whom Trichet placed his
faith, though there has been some response. Robert May, an eminent
climate change expert, has argued that techniques from his discipline
may help explain financial-market developments. Epidemiologists have
suggested that the study of how infectious diseases are propagated may
illuminate the unusual patterns of financial contagion that we have seen
in the last five years.
These are fertile fields for future
study, but what of the core disciplines of economics and finance
themselves? Can nothing be done to make them more useful in explaining
the world as it is, rather than as it is assumed to be in their stylized
models?
George Soros has put generous funding
behind the Institute for New Economic Thinking (INET). The Bank of
England has also tried to stimulate fresh ideas. The proceedings of a
conference that it organized earlier this year have now been edited
under the provocative title What’s the Use of Economics?
Some of the recommendations that emerged
from that conference are straightforward and concrete. For example,
there should be more teaching of economic history. We all have good
reason to be grateful that US Federal Reserve Chairman Ben Bernanke is
an expert on the Great Depression and the authorities’ flawed policy
responses then, rather than in the finer points of dynamic stochastic
general equilibrium theory. As a result, he was ready to adopt
unconventional measures when the crisis erupted, and was persuasive in
influencing his colleagues.
Many conference participants agreed that
the study of economics should be set in a broader political context,
with greater emphasis on the role of institutions. Students should also
be taught some humility. The models to which they are still exposed have
some explanatory value, but within constrained parameters. And painful
experience tells us that economic agents may not behave as the models
suppose they will.
But it is not clear that a majority of
the profession yet accepts even these modest proposals. The so-called
“Chicago School” has mounted a robust defense of its rational
expectations-based approach, rejecting the notion that a rethink is
required. The Nobel laureate economist Robert Lucas has argued that the
crisis was not predicted because economic theory predicts that such
events cannot be predicted. So all is well.
And there is disturbing evidence that
news of the crisis has not yet reached some economics departments.
Stephen King, Group Chief Economist of HSBC, notes that when he asks
recent university graduates (and HSBC recruits a large number of them)
how much time they spent in lectures and seminars on the financial
crisis, “most admitted that the subject had not even been raised.”
Indeed, according to King, “Young economists arrive in the financial
world with little or no knowledge of how the financial system operates.”
I am sure they learn fast at HSBC. (In
the future, one assumes, they will learn quickly about money laundering
regulations as well.) But it is depressing to hear that many university
departments are still in denial. That is not because students lack
interest: I teach a course at Sciences Po in Paris on the consequences
of the crisis for financial markets, and the demand is overwhelming.
We should not focus attention exclusively
on economists, however. Arguably the elements of the conventional
intellectual toolkit found most wanting are the capital asset pricing
model and its close cousin, the efficient-market hypothesis. Yet their
protagonists see no problems to address.
On the contrary, the University of
Chicago’s Eugene Fama has described the notion that finance theory was
at fault as “a fantasy,” and argues that “financial markets and
financial institutions were casualties rather than causes of the
recession.” And the efficient-market hypothesis that he championed
cannot be blamed, because “most investing is done by active managers who
don’t believe that markets are efficient.”
This amounts to what we might call an
“irrelevance” defense: Finance theorists cannot be held responsible,
since no one in the real world pays attention to them!
Fortunately, others in the profession do
aspire to relevance, and they have been chastened by the events of the
last five years, when price movements that the models predicted should
occur once in a million years were observed several times a week. They
are working hard to understand why, and to develop new approaches to
measuring and monitoring risk, which is the main current concern of many
banks.
These efforts are arguably as important
as the specific and detailed regulatory changes about which we hear much
more. Our approach to regulation in the past was based on the
assumption that financial markets could to a large extent be left to
themselves, and that financial institutions and their boards were best
placed to control risk and defend their firms.
These assumptions took a hard hit in the
crisis, causing an abrupt shift to far more intrusive regulation.
Finding a new and stable relationship between the financial authorities
and private firms will depend crucially on a reworking of our
intellectual models. So the Bank of England is right to issue a call to
arms. Economists would be right to heed it.
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