Ben S Bernanke: Implications of the financial crisis for economics
Speech by Mr Ben S Bernanke, Chairman of the Board of Governors of the US Federal
Reserve System, at the conference co-sponsored by the Center for Economic Policy Studies
and the Bendheim Center for Finance, Princeton, New Jersey, 24 September 2010.
* * *
Thank you for giving me this opportunity to return to Princeton. It is good to be able to catch
up with old friends and colleagues and to see both the changes and the continuities on
campus. I am particularly pleased to see that the Bendheim Center for Finance is thriving.
When my colleagues and I founded the center a decade ago, we intended it to be a place
where students would learn about not only the technicalities of modern financial theory and
practice but also about the broader economic context of financial activities. Recent events
have made clear that understanding the role of financial markets and institutions in the
economy, and of the effects of economic developments on finance, is more important than
ever.
The financial crisis that began more than three years ago has indeed proved to be among
the most difficult challenges for economic policymakers since the Great Depression. The
policy response to this challenge has included important successes, most notably the
concerted international effort to stabilize the global financial system after the crisis reached
its worst point in the fall of 2008. For its part, the Federal Reserve worked closely with other
policymakers, both domestically and internationally, to help develop the collective response
to the crisis, and it played a key role in that response by providing backstop liquidity to a
range of financial institutions as needed to stem the panic. The Fed also developed special
lending facilities that helped to restore normal functioning to critical financial markets,
including the commercial paper market and the market for asset-backed securities; led the
bank stress tests in the spring of 2009 that significantly improved confidence in the U.S.
banking system; and, in the area of monetary policy, took aggressive and innovative actions
that helped to stabilize the economy and lay the groundwork for recovery.
Despite these and other policy successes, the episode as a whole has not been kind to the
reputation of economic and economists, and understandably so. Almost universally,
economists failed to predict the nature, timing, or severity of the crisis; and those few who
issued early warnings generally identified only isolated weaknesses in the system, not
anything approaching the full set of complex linkages and mechanisms that amplified the
initial shocks and ultimately resulted in a devastating global crisis and recession. Moreover,
although financial markets are for the most part functioning normally now, a concerted policy
effort has so far not produced an economic recovery of sufficient vigor to significantly reduce
the high level of unemployment. As a result of these developments, some observers have
suggested the need for an overhaul of economics as a discipline, arguing that much of the
research in macroeconomics and finance in recent decades has been of little value or even
counterproductive.
Although economists have much to learn from this crisis, as I will discuss, I think that calls for
a radical reworking of the field go too far. In particular, it seems to me that current critiques of
economics sometimes conflate three overlapping yet separate enterprises, which, for the
purposes of my remarks today, I will call economic science, economic engineering, and
Economic science
economic management. concerns itself primarily with theoretical and
empirical generalizations about the behavior of individuals, institutions, markets, and national
economies. Most academic research falls in this category. Economic engineering is about
the design and analysis of frameworks for achieving specific economic objectives. Examples
of such frameworks are the risk-management systems of financial institutions and the
financial regulatory systems of the United States and other countries. Economic
management involves the operation of economic frameworks in real time - for example, in
the private sector, the management of complex financial institutions or, in the public sector,
the day-to-day supervision of those institutions.
As you may have already guessed, my terminology is intended to invoke a loose analogy
with science and engineering. Underpinning any practical scientific or engineering endeavor,
such as a moon shot, a heart transplant, or the construction of a skyscraper are: first,
fundamental scientific knowledge; second, principles of design and engineering, derived from
experience and the application of fundamental knowledge; and third, the management of the
particular endeavor, often including the coordination of the efforts of many people in a
complex enterprise while dealing with myriad uncertainties. Success in any practical
undertaking requires all three components. For example, the fight to control AIDS requires
scientific knowledge about the causes and mechanisms of the disease (the scientific
component), the development of medical technologies and public health strategies (the
engineering applications), and the implementation of those technologies and strategies in
specific communities and for individual patients (the management aspect). Twenty years
ago, AIDS mortality rates mostly reflected gaps in scientific understanding and in the design
of drugs and treatment technologies; today, the problem is more likely to be a lack of funding
or trained personnel to carry out programs or to apply treatments.
With that taxonomy in hand, I would argue that the recent financial crisis was more a failure
of economic engineering and economic management than of what I have called economic
science. The economic engineering problems were reflected in a number of structural
weaknesses in our financial system. In the private sector, these weaknesses included
inadequate risk-measurement and risk-management systems at many financial firms as well
as shortcomings in some firms' business models, such as overreliance on unstable
shortterm funding and excessive leverage. In the public sector, gaps and blind spots in the
financial regulatory structures of the United States and most other countries proved
particularly damaging. These regulatory structures were designed for earlier eras and did not
adequately adapt to rapid change and innovation in the financial sector, such as the
increasing financial intermediation taking place outside of regulated depository institutions
through the so-called shadow banking system. In the realm of economic management, the
leaders of financial firms, market participants, and government policymakers either did not
recognize important structural problems and emerging risks or, when they identified them,
did not respond sufficiently quickly or forcefully to address them. Shortcomings of what I
have called economic science, in contrast, were for the most part less central to the crisis;
indeed, although the great majority of economists did not foresee the near-collapse of the
financial system, economic analysis has proven and will continue to prove critical in
understanding the crisis, in developing policies to contain it, and in designing longer-term
solutions to prevent its recurrence.
I don't want to push this analogy too far. Economics as a discipline differs in important ways
from science and engineering; the latter, dealing as they do with inanimate objects rather
than willful human beings, can often be far more precise in their predictions. Also, the
distinction between economic science and economic engineering can be less sharp than my
analogy may suggest, as much economic research has direct policy implications. And
although I don't think the crisis by any means requires us to rethink economics and finance
from the ground up, it did reveal important shortcomings in our understanding of certain
aspects of the interaction of financial markets, institutions, and the economy as a whole, as I
will discuss. Certainly, the crisis should lead - indeed, it is already leading - to a greater
focus on research related to financial instability and its implications for the broader economy.
In the remainder of my remarks, I will focus on the implications of the crisis for what I have
been calling economic science, that is, basic economic research and analysis. I will first
provide a few examples of how economic principles and economic research, rather than
having misled us, have significantly enhanced our understanding of the crisis and are
informing the regulatory response. However, the crisis did reveal some gaps in economists'
knowledge that should be remedied. I will discuss some of these gaps and suggest possible
directions for future research that could ultimately help us achieve greater financial and
macroeconomic stability.
How economics helped us understand and respond to the crisis
The financial crisis represented an enormously complex set of interactions - indeed, a
discussion of the triggers that touched off the crisis and the vulnerabilities in the financial
system and in financial regulation that allowed the crisis to have such devastating effects
could more than fill my time this afternoon.1 The complexity of our financial system, and the
resulting difficulty of predicting how developments in one financial market or institution may
affect the system as a whole, presented formidable challenges. But, at least in retrospect,
economic principles and research were quite useful for understanding key aspects of the
crisis and for designing appropriate policy responses.
For example, the excessive dependence of some financial firms on unstable short-term
funding led to runs on key institutions, with highly adverse implications for the functioning of
the system as a whole. The fact that dependence on unstable short-term funding could lead
to runs is hardly news to economists; it has been a central issue in monetary economics
since Henry Thornton and Walter Bagehot wrote about the question in the 19th century.2
Indeed, the recent crisis bore a striking resemblance to the bank runs that figured so
prominently in Thornton's and Bagehot's eras; but in this case, the run occurred outside the
traditional banking system, in the shadow banking system - consisting of financial institutions
other than regulated depository institutions, such as securitization vehicles, money market
funds, and investment banks. Prior to the crisis, these institutions had become increasingly
dependent on various forms of short-term wholesale funding, as had some globally active
commercial banks. Examples of such funding include commercial paper, repurchase
agreements (repos), and securities lending. In the years immediately before the crisis, some
of these forms of funding grew especially rapidly; for example, repo liabilities of U.S.
brokerdealers increased by a factor of 2-1/2 in the four years before the crisis, and a good deal of
this expansion reportedly funded holdings of relatively less liquid securities.
In the historically familiar bank run during the era before deposit insurance, retail depositors
who heard rumors about the health of their bank - whether true or untrue - would line up to
withdraw their funds. If the run continued, then, absent intervention by the central bank or
some other provider of liquidity, the bank would run out of the cash necessary to pay off
depositors and then fail as a result. Often, the panic would spread as other banks with similar
characteristics to, or having a financial relationship with, the one that had failed came under
suspicion. In the recent crisis, money market mutual funds and their investors, as well as
other providers of short-term funding, were the economic equivalent of early-1930s retail
depositors. Shadow banks relied on these providers to fund longer-term credit instruments,
including securities backed by subprime mortgages. After house prices began to decline,
concerns began to build about the quality of subprime mortgage loans and, consequently,
about the quality of the securities into which these and other forms of credit had been
packaged. Although many shadow banks had limited exposure to subprime loans and other
questionable credits, the complexity of the securities involved and the opaqueness of many
of the financial arrangements made it difficult for investors to distinguish relative risks. In an
environment of heightened uncertainty, many investors concluded that simply withdrawing
funds was the easier and more prudent alternative. In turn, financial institutions, knowing the
risks posed by a run, began to hoard cash, which dried up liquidity and significantly limited
their willingness to extend new credit.3
Because the runs on the shadow banking system occurred in a historically unfamiliar context,
outside the commercial banking system, both the private sector and the regulators
insufficiently anticipated the risk that such runs might occur. However, once the threat
became apparent, two centuries of economic thinking on runs and panics were available to
inform the diagnosis and the policy response. In particular, in the recent episode, central
banks around the world followed the dictum set forth by Bagehot in 1873: To avert or contain
panics, central banks should lend freely to solvent institutions, against good collateral.4 The
Federal Reserve indeed acted quickly to provide liquidity to the banking system, for example,
by easing lending terms at the discount window and establishing regular auctions in which
banks could bid for term central bank credit. Invoking emergency powers not used since the
1930s, the Federal Reserve also found ways to provide liquidity to critical parts of the
shadow banking system, including securities dealers, the commercial paper market, money
market mutual funds, and the asset-backed securities market. For today's purposes, my
point is not to review this history but instead to point out that, in its policy response, the Fed
was relying on well-developed economic ideas that have deep historical roots.5 The problem
in this case was not a lack of professional understanding of how runs come about or how
central banks and other authorities should respond to them. Rather, the problem was the
failure of both private- and public-sector actors to recognize the potential for runs in an
institutional context quite different than the circumstances that had given rise to such events
in the past. These failures in turn were partly the result of a regulatory structure that had not
adapted adequately to the rise of shadow banking and that placed insufficient emphasis on
the detection of systemic risks, as opposed to risks to individual institutions and markets.
Economic research and analysis have proved useful in understanding many other aspects of
the crisis as well. For example, one of the most important developments in economics over
recent decades has been the flowering of information economics, which studies how
incomplete information or differences in information among economic agents affect market
3
See Gary B. Gorton (2008), "The Panic of 2007," paper presented at "Maintaining Stability in a Changing
Financial System," a symposium sponsored by the Federal Reserve Bank of Kansas City, held in Jackson
Hole, Wyo., August 21-23. Also see Markus K. Brunnermeier (2009), "Deciphering the Liquidity and Credit
Journal of Economic
Crunch 2007-2008," Perspectives, vol. 23 (Winter), pp. 77-100.
4
Bagehot also suggested that "these loans should only be made at a very high rate of interest" (Lombard
Street, p. 99; see note 2). Some modern commentators have rationalized Bagehot's dictum to lend at a high or
"penalty" rate as a way to mitigate moral hazard - that is, to help maintain incentives for private-sector banks
to provide for adequate liquidity in advance of any crisis. However, the risk of moral hazard did not appear to
be Bagehot's principal motivation for recommending a high rate; rather, he saw it as a tool to dissuade
unnecessary borrowing and thus help protect the Bank of England's own finite store of liquid assets. See
Bernanke, "Liquidity Provision," in note 2 for further documentation. Today, potential limitations on the central
bank's lending capacity are not nearly so pressing an issue as in Bagehot's time, when the central bank's
ability to provide liquidity was far more tenuous. Generally, the Federal Reserve lent at rates above the
"normal" rate for the market but lower than the rate prevailing in distressed and illiquid markets. This strategy
provided needed liquidity while encouraging borrowers to return to private markets when conditions
normalized.
5
A substantial modern literature has updated and formalized many of the insights of Bagehot and Thornton. A
classic example is Douglas W. Diamond and Philip H. Dybvig (1983), "Bank Runs, Deposit Insurance, and
Liquidity" Journal of Political Economy, vol. 91 (3), pp. 401-19.
BIS Review 123/2010
outcomes.6 An important branch of information economics, principal-agent theory, considers
the implications of differences in information between the principals in a relationship (say, the
shareholders of a firm) and the agents who work for the principals (say, the firm's managers).
Because the agent typically has more information than the principal - managers tend to
know more about the firm's opportunities and problems than do the shareholders, for
example - and because the financial interests of the principal and the agent are not perfectly
aligned, much depends on the contract (whether explicit or implicit) between the principal
and the agent, and, in particular, on the incentives that the contract provides the agent.
Poorly structured incentives were pervasive in the crisis. For example, compensation
practices at financial institutions, which often tied bonuses to short-term results and made
insufficient adjustments for risk, contributed to an environment in which both top managers
and lower-level employees, such as traders and loan officers, took excessive risks. Serious
problems with the structure of incentives also emerged in the application of the so-called
originate-to-distribute model to subprime mortgages. To satisfy the strong demand for
securitized products, both mortgage lenders and those who packaged the loans for sale to
investors were compensated primarily on the quantity of "product" they moved through the
system. As a result, they paid less attention to credit quality and many loans were made
without sufficient documentation or care in underwriting. Conflicts of interest at credit
agencies, which were supposed to serve investors but had incentives to help issuers of
securities obtain high credit ratings, are another example.
Consistent with key aspects of research in information economics, the public policy
responses to these problems have focused on improving market participants' incentives. For
example, to address problems with compensation practices, the Federal Reserve, in
conjunction with other supervisory agencies, has subjected compensation practices of
banking institutions to supervisory review. The interagency supervisory guidance supports
compensation practices that induce employees to take a longer-term perspective, such as
paying part of employees' compensation in stock that vests based on sustained strong
performance. To ameliorate the problems with the originate-to-distribute model, recent
legislation requires regulatory agencies, including the Federal Reserve, to develop new
standards applicable to securitization activities that would better align the incentives faced by
market participants involved in the various stages of the securitization process.7 And the
Securities and Exchange Commission has been charged with developing new rules to
reduce conflicts of interest at credit rating agencies.
6
George Akerlof, A. Michael Spence, and Joseph Stiglitz shared the 2001 Nobel Prize in Economics for their
leadership in the development of information economics.
7
The requirements related to credit risk were contained in section 941 of the Dodd-Frank Wall Street Reform
and Consumer Protection Act, Pub. L. No. 111-203 (July 2010); with regard to compensation practices, see
Board of Governors of the Federal Reserve System (2009), "Federal Reserve Issues Proposed Guidance on
Incentive Compensation," press release, October 22; also see Board of Governors of the Federal Reserve
System (2010), "Federal Reserve, OCC, OTS, FDIC Issue Final Guidance on Incentive Compensation," joint
press release, June 21.
Why might government intervention be needed to improve private-sector incentives, when incentives
presumably exist for the private-sector principals and agents to work out the best incentive structure for
themselves? The possibility of problems arising regarding collective action when a firm has many
shareholders is one rationale. The standard reason for intervening in banks' risk-taking practices is the
existence of deposit insurance, which itself distorts private risk-taking incentives by eliminating any incentive
of depositors to monitor the activities of their bank; for an early discussion, see John Kareken and Neil
Wallace (1978), "Deposit Insurance and Bank Regulation: A Partial-Equilibrium Exposition," Journal of
Business, vol. 51 (July), pp. 413-38. Indeed, the Federal Reserve invoked a "safety and soundness" rationale
for its guidance on incentive compensation practices. More generally, as the crisis revealed, bad incentives
can lead to problems that affect not just the individuals involved but the broader financial system as well; such
spillovers suggest that regulation can help improve outcomes.
BIS Review 123/2010
Information economics and principal-agent theory are also essential to understanding the
problems created by so-called too-big-to-fail financial institutions. Prior to the crisis, market
participants believed that large, complex, and interconnected financial firms would not be
allowed to fail during a financial crisis. And, as you know, authorities both in the United
States and abroad did in fact intervene on a number of occasions to prevent the failure of
such firms - not out of any special consideration for the owners, managers, or creditors of
these firms, but because of legitimate concerns about potential damage to the financial
system and the broader economy. However, although the instability caused by the failure or
near-failure of some large firms did indeed prove very costly, in some sense the real damage
was done before the crisis. If creditors in good times believe that certain firms will not be
allowed to fail, they will demand relatively little compensation for risk, thus weakening market
discipline; in addition, creditors will not have much incentive to monitor the firms' risk-taking.
As a result, as predicted by principal-agent theory, firms thought to be too big to fail tended to
take on more risk, as they faced little pressure from investors and expected to receive
assistance if their bets went bad. This problem is an example of what economists refer to as
moral hazard. The resulting buildup of risk in too-big-to-fail firms increased the likelihood that
a financial crisis would occur and worsened the crisis when it did occur.
One response to excessive risk-taking is stronger oversight by regulators, and the recent
legislation and the rules and procedures being developed by the Federal Reserve and other
agencies will subject systemically critical firms to tougher regulatory requirements and stricter
supervision. The Federal Reserve has also been involved in international negotiations to
raise the capital and liquidity that banks are required to hold. However, the problem of
toobig-to-fail can only be eliminated when market participants believe authorities' statements
that they will not intervene to prevent failures. If creditors believe that the government will not
rescue firms when their bets go bad, then creditors will have more-appropriate incentives to
price, monitor, and limit the risk-taking of the firms to which they lend. The best way to
achieve such credibility is to create institutional arrangements under which a failure can be
allowed to occur without widespread collateral damage; if failures can take place more
safely, the authorities will no longer have an incentive to try to avoid them. The financial
reform legislation took an important step in this direction by creating a resolution regime
under which large, complex financial firms can be placed in receivership, but which also
gives the government the flexibility to take the actions needed to safeguard systemic stability.
This new regime should help restore market discipline by putting a greater burden on
creditors and counterparties to monitor the risk-taking of large financial firms.
The insights of economists proved valuable to policymakers in many other contexts as well:
in the setting and oversight of bank capital standards, in the decision to provide the market
with extensive information gleaned during the bank stress tests in the spring of 2009, in the
design of the Fed's liquidity facilities for nondepository institutions, in the analysis of the
collapse of the securitization market, and in the measures taken to protect consumers from
deceptive or inappropriate lending, to name a few. Many of the key ideas, like those of
Thornton and Bagehot, were quite old, but some reflected relatively recent research. For
example, recent work on monetary policy helped the Federal Reserve provide further policy
accommodation despite the constraints imposed by the zero lower bound on interest rates.8
Economics and economic research in the wake of the crisis
Economic principles and research have been central to understanding and reacting to the
crisis. That said, the crisis and its lead up also challenged some important economic
principles and research agendas. I will briefly indicate some areas that, I believe, would
benefit from more attention from the economics profession.
Most fundamentally, and perhaps most challenging for researchers, the crisis should
motivate economists to think further about their modeling of human behavior. Most economic
researchers continue to work within the classical paradigm that assumes rational,
selfinterested behavior and the maximization of "expected utility" - a framework based on a
formal description of risky situations and a theory of individual choice that has been very
useful through its integration of economics, statistics, and decision theory.9 An important
assumption of that framework is that, in making decisions under uncertainty, economic
agents can assign meaningful probabilities to alternative outcomes. However, during the
worst phase of the financial crisis, many economic actors - including investors, employers,
and consumers - metaphorically threw up their hands and admitted that, given the extreme
and, in some ways, unprecedented nature of the crisis, they did not know what they did not
know. Or, as Donald Rumsfeld might have put it, there were too many "unknown unknowns."
The profound uncertainty associated with the "unknown unknowns" during the crisis resulted
in panicky selling by investors, sharp cuts in payrolls by employers, and significant increases
in households' precautionary saving.
The idea that, at certain times, decisionmakers simply cannot assign meaningful probabilities
to alternative outcomes - indeed, cannot even think of all the possible outcomes - is known
as Knightian uncertainty, after the economist Frank Knight who discussed the idea in the
1920s. Although economists and psychologists have long recognized the challenges such
ambiguity presents and have analyzed the distinction between risk aversion and ambiguity
aversion, much of this work has been abstract and relatively little progress has been made in
describing and predicting the behavior of human beings under circumstances in which their
knowledge and experience provide little useful information.10 Research in this area could aid
our understanding of crises and other extreme situations. I suspect that progress will require
careful empirical research with attention to psychological as well as economic factors.
Another issue that clearly needs more attention is the formation and propagation of asset
price bubbles. Scholars did a great deal of work on bubbles after the collapse of the dot-com
bubble a decade ago, much of it quite interesting, but the profession seems still quite far from
consensus and from being able to provide useful advice to policymakers. Much of the
literature at this point addresses how bubbles persist and expand in circumstances where we
would generally think they should not, such as when all agents know of the existence of a
bubble or when sophisticated arbitrageurs operate in a market. As it was put by my former
colleague, Markus Brunnermeier, a scholar affiliated with the Bendheim center who has done
9
Herein I use the extension of Von Neumann-Morgenstern expected utility, which focused on objective
probabilities over risks, to situations in which individuals assign subjective probabilities over risks. For a review
of some classic contributions in this area, see Jacques H. Drèze (1974), "Axiomatic Theories of Choice,
Cardinal Utility and Subjective Probability: A Review," in Jacques H. Drèze, ed., Allocation under Uncertainty:
Equilibrium and Optimality (London: Macmillan), pp. 3-23. Some authors have used risk to refer to a situation
of objective probabilities and uncertainty to refer to a situation of subjective probabilities (see, for example,
David M. Kreps (1990), A Course in Microeconomic Theory (Princeton, N.J.: Princeton University Press)). As
highlighted below, others refer to uncertainty as a situation in which subjective probabilities cannot be
assessed. As this discussion makes clear, it is probably best to focus on the context in which the terms risk
and uncertainty are used.
10
The classic reference on ambiguity aversion is due to Daniel Ellsberg (1961), "Risk, Ambiguity, and the
Savage Axioms," The Quarterly Journal of Economics, vol. 75 (4), pp. 643-69; for a more recent, and
abstract, theoretical treatment, see Larry G. Epstein (1999), "A Definition of Uncertainty Aversion," Review of
Economic Studies, vol. 66 (July), pp. 579-608.
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important research on bubbles, "We do not have many convincing models that explain when
and why bubbles start."11 I would add that we also don't know very much about how bubbles
stop either, and better understanding this process - and its implications for the household,
business, and financial sectors - would be very helpful in the design of monetary and
regulatory policies.
Another issue brought to the fore by the crisis is the need to better understand the
determinants of liquidity in financial markets. The notion that financial assets can always be
sold at prices close to their fundamental values is built into most economic analysis, and
before the crisis, the liquidity of major markets was often taken for granted by financial
market participants and regulators alike. The crisis showed, however, that risk aversion,
imperfect information, and market dynamics can scare away buyers and badly impair price
discovery. Market illiquidity also interacted with financial panic in dangerous ways. Notably, a
vicious circle sometimes developed in which investor concerns about the solvency of
financial firms led to runs: To obtain critically needed liquidity, firms were forced to sell assets
quickly, but these "fire sales" drove down asset prices and reinforced investor concerns
about the solvency of the firms. Importantly, this dynamic contributed to the profound blurring
of the distinction between illiquidity and insolvency during the crisis. Studying liquidity and
illiquidity is difficult because it requires going beyond standard models of market clearing to
examine the motivations and interactions of buyers and sellers over time.12 However, with
regulators prepared to impose new liquidity requirements on financial institutions and to
require changes in the operations of key markets to ensure normal functioning in times of
stress, new policy-relevant research in this area would be most welcome.
I have been discussing needed research in microeconomics and financial economics but
have not yet touched on macroeconomics. Standard macroeconomic models, such as the
workhorse new-Keynesian model, did not predict the crisis, nor did they incorporate very
easily the effects of financial instability. Do these failures of standard m