Category Archives: General

Ken Arrow – Financial turmoil is a challenge to economic theory

On Comment is Free, economist Kenneth Arrow writes that The financial turmoil is a challenge to economic theory

The current financial crisis, the loss of asset values, the refusal to extend normally-given credit and the great increase in defaults on obligations ranging from individual mortgages to the debts of great investment banks presents, of course, a pressing challenge to the fiscal authorities and central banks to take measures to minimise the consequences. But they also present a challenge to standard economic theory, a challenge all the more important since the development of policies to prevent future financial crises will depend on a deeper understanding of the processes at work.

That economic decisions are made without certain knowledge of the consequences is pretty self-evident. But, although many economists were aware of this elementary fact, there was no systematic analysis of economic uncertainty until about 1950. There have been two developments in the economic theory of uncertainty in the last 60 years, which have had opposite implications for the radical changes in the financial system. One has made explicit and understandable a long tradition that spreading risks among many bearers improves the functioning of the economy. The second is that there are large differences of information among market participants and that these differences are not well handled by market forces. The first point of view tends to argue for the expansion of markets, the second for recognising that they may fail to exist and, if they do come into being, may fail to work for the benefit of the general economic situation.

There is obviously much more to the full understanding of the current financial crisis, but the root is this conflict between the genuine social value of increased variety and spread of risk-bearing securities and the limits imposed by the growing difficulty of understanding the underlying risks imposed by growing complexity.

James K. Galbraith economics and the financial crisis

An interview with economist James Galbraith in the NYTimes.com

..There are at least 15,000 professional economists in this country, and you’re saying only two or three of them foresaw the mortgage crisis? Ten or 12 would be closer than two or three.

What does that say about the field of economics, which claims to be a science? It’s an enormous blot on the reputation of the profession. There are thousands of economists. Most of them teach. And most of them teach a theoretical framework that has been shown to be fundamentally useless.

And a review of the impact of the crisis.

During the go-go investing years, school districts, transit agencies and other government entities were quick to jump into the global economy, hoping for fast gains to cover growing pension costs and budgets without raising taxes. Deals were arranged by armies of persuasive financiers who received big paydays.

But now, hundreds of cities and government agencies are facing economic turmoil. Far from being isolated examples, the Wisconsin schools and New York’s transportation system are among the many players in a financial fiasco that has ricocheted globally.

Books on global sustainability

From the New Scientist, reviews of twelve recent books on consumption and sustainability:

Continue reading

Increasing sustainability science at universities

From Naturejobs

Scientists who seek intensely interdisciplinary study could be the beneficiaries of increasing interest in the emerging field of sustainability research, with new university programmes offering novel opportunities. Portland State University in Oregon and Cornell University in Ithaca, New York, are the most recent entrants to the field. They follow the example set by institutions such as the School of Sustainability at Arizona State University in Tempe.

Broadly defined, sustainability bridges disciplines to determine how to meet the resource needs of the present without adversely affecting future generations. In practice, that means assembling teams of ecologists, economists, biologists and social scientists to find solutions and strategies for big problems, such as meeting future energy needs.

Turbulence and Finance: Taleb and Mandelbrot

On PBS’s NewsHour, Paul Solman interviewed Nassim Nicholas Taleb and Benoit Mandelbrot about how strongly coupled systems can produce unpredictable turbulence.  They strike very resilience oriented themes – narrow over-optimization leading to a loss of resilience.

PAUL SOLMAN: In the [Black Swan], Taleb wrote, “The increased concentration among banks seems to have the effect of making financial crises less likely. But when they happen, they are more global in scale and hit us very hard. True, we now have fewer failures, but, when they occur, I shiver at the thought.”

NASSIM NICHOLAS TALEB: The banking system, the way we have it, is a monstrous giant built on feet of clay. And if that topples, we’re gone.

Never in the history of the world have we faced so much complexity combined with so much incompetence and understanding of its properties.

PAUL SOLMAN: But there’s been complexity before. There has been overextension of credit before. We’ve had crashes in American history many times before. We’re a resilient system. Won’t we pull out of it?

NASSIM NICHOLAS TALEB: Let me tell you why it’s not like before. Look at what’s happening. The world is getting so fragile that a small shortage of oil — small — can lead to the price going from $25 to $150.

PAUL SOLMAN: A barrel.

NASSIM NICHOLAS TALEB: A barrel. A small excess demand in an agricultural product can lead to an explosion in price.

We live in a world that is way too complicated for our traditional economic structure. It’s not as resilient as it used to be. We don’t have slack. It’s over-optimized.

PAUL SOLMAN: What do you mean by “over-optimized”?

NASSIM NICHOLAS TALEB: Let me tell you what is happening in the ecology of the banking system. They’re swelling to large banks, OK, because it’s vastly more optimal to have one large bank than 10 small banks. It’s more efficient.

PAUL SOLMAN: Well, we’ve certainly seen the consolidation of the industry.

NASSIM NICHOLAS TALEB: Exactly. And that consolidation is what’s putting us at risk, because we are — when one bank, large bank makes a mistake, OK, it’s 10 times worse than a small bank making a mistake.

PAUL SOLMAN: So, getting back to your fundamental work and insight, this is a system that can become turbulent or is inherently turbulent, that doesn’t have enough of a buffer, and that’s the danger?BENOIT MANDELBROT: That is not well-understood. In fact, that is misunderstood for which tools have been developed which assume that changes are always very small.

If one of them comes, nothing bad happens. If several of them come together, very bad things have happened. And the theory does not take account of that, and the theory doesn’t take account of very large and sudden changes in anything.

The theory thinks that things move slowly, gradually, and can be corrected as they change, whereas, in fact, they may change extremely brutally.

NASSIM NICHOLAS TALEB: Now you understand why I’m worried. I hope I’m wrong. I wake up every morning — actually, I don’t wake up every morning now. I start to wake up at night the last couple of weeks hoping that I’m wrong, begging to be wrong.

I think that we may be experiencing something that is vastly worse than we think it is.

PAUL SOLMAN: And we think it’s pretty bad.

NASSIM NICHOLAS TALEB: It’s worse. Of all the books you read on globalization, they talk about efficiency, all that stuff. They don’t get the point. The network effect of that globalization, OK, means that a shock in the system can have much larger consequences.

via Global Guerrillas

Assorted financial crisis news and analysis

The US radio show This American Life has an informative show on how non-transparent couplings between credit default swaps allowed caused the contagion that was critical to the financial crisis – Another Frightening Show About the Economy. You can listen to their show online or download an MP3 file.

Also see economist Paul Krugman on the financial crisis here and with a longer analysis here. He also posts a revealing graph which shows the how the strength of the coupling between the US and the rest of the world’s (ROW) economies has increased over the past thirty years.

The US TV show 60 Minutes has a 12 min. segment on the “Shadow Financial System“. The segment charges the managers of investment banks with criminal incompetence.


Watch CBS Videos Online

Also, the New York Times, a critical look at the deregulation of financial markets under the US Federal Reserve chairmanship of Alan Greenspan. Taking Hard New Look at a Greenspan Legacy

“Not only have individual financial institutions become less vulnerable to shocks from underlying risk factors, but also the financial system as a whole has become more resilient.” — Alan Greenspan in 2004

And in the UK’s Financial Times, columnist Martin Wolf writes that is is now time for a comprehenisive plan to rescue the financial system:

As John Maynard Keynes is alleged to have said: “When the facts change, I change my mind. What do you do, sir?” I have changed my mind, as the panic has grown. Investors and lenders have moved from trusting anybody to trusting nobody. The fear driving today’s breakdown in financial markets is as exaggerated as the greed that drove the opposite behaviour a little while ago. But unjustified panic also causes devastation. It must be halted, not next week, but right now.
The time for a higgledy-piggledy, institution-by-institution and country-by-country approach is over. It took me a while – arguably, too long – to realise the full dangers. Maybe it was errors at the US Treasury, particularly the decision to let Lehman fail, that triggered today’s panic. So what should be done? In a word, “everything”. The affected economies account for more than half of global output. This makes the crisis much the most significant since the 1930s.

PhD position at Stockholm Resilience Centre

As mentioned earlier on this blog, Line Gordon and I are looking for a PhD student to be part of an international research project.

The PhD position is at Stockholm University (Sweden) in Physical Geography, but the student will be based at both Physical Geography and the Stockholm Resilience Centre.

The student will develop a conceptual framework and empirical methods to investigate how globally driven hydrological changes could alter the social-ecological resilience of Arctic ecosystems. This research includes reviewing evidence for possible hydrologically triggered abrupt threshold changes or regime shifts in Arctic ecosystems, the synthesis of existing social, ecological and physical data to map social-ecological resilience in the Arctic, and the construction of minimal social-ecological models of Arctic regime shifts.

The proposed starting date is January 1, 2009 (although this can be negotiated). Applications will be taken until Oct 31th, 2008.

For more information see my previous post.

The official job ad and details are here.

Systemic risk reflections

TED spreadSome recent reflections on systemic risk and the financial markets – ranging from details to the big picture.

First, Gretchen Morgenson in the New York Times writes Behind Insurer’s Crisis, Blind Eye to a Web of Risk:

“It is hard for us, without being flippant, to even see a scenario within any kind of realm of reason that would see us losing one dollar in any of those transactions.”— Joseph J. Cassano, a former A.I.G. executive, August 2007

…Although America’s housing collapse is often cited as having caused the crisis, the system was vulnerable because of intricate financial contracts known as credit derivatives, which insure debt holders against default. They are fashioned privately and beyond the ken of regulators — sometimes even beyond the understanding of executives peddling them.

Originally intended to diminish risk and spread prosperity, these inventions instead magnified the impact of bad mortgages like the ones that felled Bear Stearns and Lehman and now threaten the entire economy.

In the case of A.I.G., the virus exploded from a freewheeling little 377-person unit in London, and flourished in a climate of opulent pay, lax oversight and blind faith in financial risk models. It nearly decimated one of the world’s most admired companies, a seemingly sturdy insurer with a trillion-dollar balance sheet, 116,000 employees and operations in 130 countries.

Second, America’s National Public Radio’s Planet Money has a lot of recent indepth coverage of the financial crisis in this vein available of podcasts.  Including a recent one called the day America’s economy almost died.

Looking a more the big economic picture,  Predicting Crisis in the United States Economy a profile of Nouriel Roubini discusses the selective vision of models and the biases against discontinuities or nonlinear change.

Recessions are signal events in any modern economy. And yet remarkably, the profession of economics is quite bad at predicting them. A recent study looked at “consensus forecasts” (the predictions of large groups of economists) that were made in advance of 60 different national recessions that hit around the world in the ’90s: in 97 percent of the cases, the study found, the economists failed to predict the coming contraction a year in advance. On those rare occasions when economists did successfully predict recessions, they significantly underestimated the severity of the downturns. Worse, many of the economists failed to anticipate recessions that occurred as soon as two months later.

The dismal science, it seems, is an optimistic profession. Many economists, Roubini among them, argue that some of the optimism is built into the very machinery, the mathematics, of modern economic theory. Econometric models typically rely on the assumption that the near future is likely to be similar to the recent past, and thus it is rare that the models anticipate breaks in the economy. And if the models can’t foresee a relatively minor break like a recession, they have even more trouble modeling and predicting a major rupture like a full-blown financial crisis. Only a handful of 20th-century economists have even bothered to study financial panics. (The most notable example is probably the late economist Hyman Minksy, of whom Roubini is an avid reader.) “These are things most economists barely understand,” Roubini told me. “We’re in uncharted territory where standard economic theory isn’t helpful.”

Finally, Science Fiction writer Charlie Stross writes about the increasing difficulty of projecting the near future at all:

We are living in interesting times; in fact, they’re so interesting that it is not currently possible to write near-future SF.

… Put yourself in the shoes of an SF author trying to construct an accurate (or at least believable) scenario for the USA in 2019. Imagine you are constructing your future-USA in 2006, then again in 2007, and finally now, with talk of $700Bn bailouts and nationalization of banks in the background. Each of those projections is going to come out looking different. Back in 2006 the sub-prime crisis wasn’t even on the horizon but the big scandal was FEMA’s response (or lack thereof) to Hurricane Katrina. In 2007, the sub-prime ARM bubble began to burst and the markets were beginning to turn bearish. (Oh, and it looked as if the 2008 presidential election would probably be down to a fight between Hilary Clinton and Rudy Giuliani.) Now, in late 2008 the fiscal sky is falling; things may not end as badly as they did for the USSR, but it’s definitely an epochal, historic crisis.

Now extend the thought-experiment back to 1996 and 1986. Your future-USA in the 1986 scenario almost certainly faced a strong USSR in 2019, because the idea that a 70 year old Adversary could fall apart in a matter of months, like a paper tiger left out in a rain storm, simply boggles the mind. It’s preposterous; it doesn’t fit with our outlook on the way history works. (And besides, we SF writers are lazy and we find it convenient to rely on clichés — for example, good guys in white hats facing off against bad guys in black hats. Which is silly — in their own head, nobody is a bad guy — but it makes life easy for lazy writers.) The future-USA you dreamed up in 1996 probably had the internet (it had been around in 1986, in embryonic form, the stomping ground of academics and computer industry specialists, but few SF writers had even heard of it, much less used it) and no cold war; it would in many ways be more accurate than the future-USA predicted in 1986. But would it have a monumental fiscal collapse, on the same scale as 1929? Would it have Taikonauts space-walking overhead while the chairman of the Federal Reserve is on his knees? Would it have more mobile phones than people, a revenant remilitarized Russia, and global warming?

There’s a graph I’d love to plot, but I don’t have the tools for. The X-axis would plot years since, say, 1950. The Y-axis would be a scatter plot with error bars showing the deviation from observed outcomes of a series of rolling ten-year projections modeling the near future. Think of it as a meta-analysis of the accuracy of projections spanning a fixed period, to determine whether the future is becoming easier or harder to get right. I’m pretty sure that the error bars grow over time, so that the closer to our present you get, the wider the deviation from the projected future would be. Right now the error bars are gigantic.

PhD Position at Stockholm Resilience Centre

Line Gordon and I are looking for a PhD student to be part of an international research project that will examine social-ecological resilience of Arctic ecosystems to changes in hydrological flows.

The PhD position is at Stockholm University (Sweden) in Physical Geography, but the student will be based at both Physical Geography and the Stockholm Resilience Centre.

The PhD student will develop a conceptual framework and empirical methods to investigate how globally driven hydrological changes could alter the social-ecological resilience of Arctic ecosystems. This research includes reviewing evidence for possible hydrologically triggered abrupt threshold changes or regime shifts in Arctic ecosystems, the synthesis of existing social, ecological and physical data to map social-ecological resilience in the Arctic, and the construction of minimal social-ecological models of Arctic regime shifts.

Qualifications: The successful candidate should be enthusiastic about conducting trans-disciplinary studies and is expected to have a background in physical geography and/or ecology and have substantial knowledge of global environmental change. Knowledge of resilience theory, hydrology, and the Arctic are desired. A good command of English is required and experience in geographical information systems (GIS). Experience in modeling, GIS, remote sensing, geostatistics and data fusion are merits.

This PhD project is part of a larger research project on Pan-Arctic ice-water-biogeochemical system responses and social-ecological resilience effects in a warming climate, which is coordinated from the Department of Physical Geography and Quaternary Geology and involves collaborators from the Bert Bolin Centre for Climate Research and the Stockholm Resilience Centre at Stockholm University as well as international collaborators.

The proposed starting date is January 1, 2009 (although this can be negotiated).  Applications are due by Oct 31th, 2008.

The official job ad and details are here.

Furthermore, Stockholm University is particularly exciting places to work on resilience and water.  The Stockholm Resilience Centre hosts a world leading research group on social-ecological resilience, and Physical Geography and the Resilience Centre both contain world leading water researchers.  The student will be part of a small group of PhD students linked to this project and will have the opportunity to work with researchers from both groups.

This project will build upon previous work that Line Gordon and I have done on mapping hydrological flows, resilience and ecological regime shifts.  Some of our papers that this work will build on include:

  1. Gordon LJ, Peterson GD, Bennett EB.  2008.  Agricultural modifications of hydrological flows create ecological surprises. Trends in Ecology and Evolution.  23(4):211-219.
  2. Chapin et al.  2006.  Policy strategies to address sustainability of Alaskan boreal forests in response to a directionally changing climate.  Proceedings National Academy of Sciences, USA 103:16637–16643.
  3. Gordon L., et al. (2005) Human modification of global water vapor flows from the land surface. Proceedings National Academy of Sciences, USA 102: 7612-7617.
  4. Bennett, EM, GS Cumming, GD Peterson. 2005. A systems model approach to determining resilience surrogates for case studies, Ecosystems 8(8): 945-957.
  5. Peterson, G.D., S. Carpenter, and W.A. Brock. 2003. Model uncertainity and the management of multi-state ecosystems: a rational route to collapse. Ecology. 84(6) 1403-1411.
  6. Peterson, G.D. 2002. Estimating resilience across landscapes. Conservation Ecology 6(1): 17.
  7. Peterson, G., C. R. Allen, and C. S. Holling. 1998. Ecological resilience, biodiversity and scale. Ecosystems 1(1): 6-18.

The Shrinking Aral Sea

Another image showing the ecological destruction of the Aral Sea.

Aral Sea 2000-2008

From EO Newsroom:

This natural-color satellite image shows the Aral Sea on August 16, 2008. The colored contour lines show the approximate shorelines of the sea since 2000. The image is from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite. The contour lines are based on MODIS data from both the Aqua and Terra satellites. The image documents the progress of a conservation plan to stabilize the North Aral Sea, and the continued decline of the South Aral Sea. Deeper, clearer waters are darker blue; shallower, murkier waters are greenish.

A dam separates the northern and southern parts of the sea, allowing the flow of the Syrdar’y to recharge the North Aral Sea. Meanwhile, the South Aral Sea continues to dry out. The lake has split into eastern and western lobes, with the eastern lobe drying more rapidly. The lakebed is lined with pale, salty sediment, which is kicked up during dust storms. The lakebed sediments also contain agricultural chemical residues and other pollutants, which have contributed to widespread public health problems.

The transformation of the lake into dry land changed the regional climate. Previously, the large lake helped to stabilize the area’s continental climate. Continental climates exhibit large seasonal extremes in temperature. Compared to locations at the same latitude, places with continental climates have hotter summers and colder winters; they are also drier. As the Aral Sea has disappeared, summers have become even hotter, winters have become colder and longer, and the dry climate has become drier.