Sobre este ponto têm-se escrito, e discutido, imenso: no The Economist, no Financial Times, etc., nos blogues destes jornais, na blogosfera dos economistas. Não acompanhei tudo, e muito do que guardei (no Delicious) ficou para ler depois, daí que o que vem abaixo (que é muito, mas é para arrumar a casa), nem é tudo, nem asseguro que seja o mais interessante, mas tem interesse suficiente para merecer uma leitura.
O artigo Experts & the demand for certainty, by Chris Dillow, não se enquadra bem sob a epigrafe desta nota, mas fica aqui porque acaba por estar ligada à discussão, ainda que indirectamente - é por ele, e por aquele que o segue, que esta nota é classificada com a etiqueta falácias:
- Paul Krugman's Views differ on the shape of macroeconomics "I’ll mostly weigh in on Brad DeLong’s side with regard to this Economist piece on the state of macroeconomics. The Economist reaches, I think, for a false symmetry, and glosses over too easily the sheer ignorance that has become obvious in the debates over fiscal policy. On the other hand, the common claim that economists ignored the financial side and the risks of crisis seems not quite fair — at least from where I sit. In international macro, one of my two home fields, we’ve worried about and tried to analyze crises a lot. Especially after the Asian crisis of 1997-98, financial crises were very much on everyone’s mind. There was a substantial empirical literature from economists like Carmen Reinhart and Graciela Kaminsky (with Ken Rogoff joining in latterly); there was modeling from Guillermo Calvo, Jose Velasco, Nouriel Roubini, Paolo Pesenti, and others, including yours truly. Speaking for myself, I saw the housing bubble and expected the bust; but I hadn’t appreciated in advance either the vulnerability of the shadow banking system or the leverage of American consumers. Once the crisis was underway, however, I had a more or less ready-made intellectual framework to accommodate these revelations: at a meta level, this was very much the same kind of crisis as Indonesia 1998 or Argentina 2002. Domestic macro people may have been more astonished by what happened. But the prevailing trend now is to assert that there are more risks in the economy than were dreamed of in our philosophy; I don’t think that’s fair".
- Economist's View: "Economists on Trial" This is part of an interview of heterodox economist Michael Perelman: Michael Perelman, on Market Myths, Past and Present, by Seth Sandronsky: ...[Seth] Sandronsky The Depression of the 1930's changed the public policy views of some in the economics profession. In brief, what were the main changes, and how do they connect with the post-bubble economy of mid-2009? Perelman The Great Depression severely tarnished economists' reputations. For example, The Economist published an article on 17 June 1933, entitled "Economists on Trial," which described a "mock-trial - not entirely mockery -" of "the economists." The trial was staged at the London School of Economics, with Robert Boothby, M.P., representing "the state of the popular mind." He accused the economists with "conspiring to spread mental fog," charging that they "were unintelligible; that they had in general proved wrong; and that in any case they all disagreed." The economists - Sir William Beveridge, Sir Arthur Salter, Professor T. E. Gregory, and Hubert Henderson - were all highly respected in the field. They answered Boothby's charges without wholly refuting them. The article concluded, "There was never a time when the advice of an expert was so often asked and so seldom followed as the present." According to the magazine, the problem was that the authorities did not listen to the economists. At the same time, during the New Deal economists played a very prominent role. For the most part, they had not previously been among the doctrinaire defenders of laissez-faire. But keep in mind that, until the post-World War II era, the economics profession was much more diverse. A good number of progressive economists had been purged from academia, but some progressives remained. The more elite a university was, the less diversity it had. Yet, even in elite universities there was a modicum of diversity. Although the discipline of economics became radically more conservative after World War II, during the 1970's economists who were active during the Depression tended to give me a much more sympathetic hearing, even if they had drifted considerably to the right. Today, the makeup of the economics profession has changed dramatically. The economists who experienced the Great Depression are gone. On virtually any campus, the economics department will be among the most conservative. Dissenting views are rarely tolerated, except in liberal arts colleges. Catholic colleges also tend to be less fearful of unorthodox views. However, the government's stimulus plans - under both Bush and Obama - have been so inept that a good number of very conservative economists have been highly critical in ways that do not entirely differ from my own. Perhaps what is most surprising is how little influence economists have had in the policy realm. Virtually no Congressional hearings have called upon economists, whether they are conventional or radical. How much influence economists - other than Larry Summers - have had behind closed doors is an open question. ...
- Experts & the demand for certainty, by Chris Dillow: It’s a bad day for experts. The Timescomplains that economic forecasters are as blind as ancient soothsayers, whilst proof that Colin Stagg was innocent discredits Paul Britton’s expertise as a forensic pyschologist. To point out that experts are wrong, however, is to misunderstand the purpose of them. Their function is not to provide knowledge, and still less clear thinking. Instead, it is to provide certainty. People hate dissonance, doubt and uncertainty. Experts help dispel these. So, Paul Britton’s function was to tell the police that they had the right man, whilst economic forecasters’ job is to provide an impression that the future is knowable; no-one wants to hear about standard errors, parameter uncertainty or the Lucas critique. What’s so pernicious here, though, is that people have ways of achieving an illusory certainty anyway. As Sir Harry Ognall - the judge who acquitted Stagg -says: “The police closed their minds to any other possibility than that of his guilt.” There are several ways they got these closed minds. All have analogues in corporate planning and financial trading. 1. The confirmation bias. Having acquired the belief that Stagg was guilty - he fitted the profile, was on the scene and a bit of a weirdo - subsequent evidence was interpreted as corroborating this. So, the fact that he looked shifty in interview was seen as evidence of guilt, not as the sign of an innocent man nervous of being fitted up. A similar thing happens in economic forecasting. If you thought last week that we’re heading for a very deep recession, you put great weight on Wednesdays’s jobless numbers and find ways of dismissing yesterday’sretail sales figures. If you thought the recession would be mild, you do the opposite. 2. The halo effect. In their book, Mistakes were Made, Carol Tavris and Elliot Aronson describe how policemen believe “I couldn’t have been wrong because I’m a good guy.” Even if we grant the premise, the error here lies in believing that good qualities - moral rectitude and cognitive skills - must be correlated. They are not. Of course, coppers are not unique in thinking this. 3.Groupthink. If our colleagues agree with us, our confidence in our judgment rises, especially if we like them. This error arises in part because we fail to see that correlated data points add little to certainty. If our colleagues have the same training and evidence as us, and are also prone to groupthink, their beliefs will be correlated with ours, and so will not be new evidence - no more than a second copy of the Daily Mail corroborates the stories made in the first. But we interpret them as if they are. 4. Ego-involvement. Admitting that we are wrong means more than just fessing up to narrow technical error. We interpret it as a blow to our ego - a sign that we are not the infallible, uber-competent professionals we think. We’ll do anything to squirm out of facing this. Hence the failure of the police, until yesterday, to apologize to Colin Stagg, and the failure of many bank bosses, Tom McKillop excepted, to apologize for their errors. And herein lies the purpose of experts. It’s to reinforce these mechanisms, to help people avoid the uncomfortable facts that the world is uncertain, that mistakes are inevitable, and that we are not as in control of things as we think. Blaming experts for being wrong is like complaining that the economy is not yellow. It’s a category error so howling as to be nonsensical.
- EVER wondered why the pundits who failed to predict the current economic crisis are still being paid for their opinions? It's a consequence of the way human psychology works in a free market, according to a study of how people's self-confidence affects the way others respond to their advice. The research, by Don Moore of Carnegie Mellon University in Pittsburgh, Pennsylvania, shows that we prefer advice from a confident source, even to the point that we are willing to forgive a poor track record. Moore argues that in competitive situations, this can drive those offering advice to increasingly exaggerate how sure they are. And it spells bad news for scientists who try to be honest about gaps in their knowledge. Humans prefer cockiness to expertise - life - 10 June 2009 - New Scientist
- The Anti-Macroeconomics Roar Grows Louder - Freakonomics Blog - NYTimes.com In my opinion, the fundamental problem is this: from a modern academic perspective, the sorts of skills that accompany having a good working knowledge of the macroeconomy are not easily measured by, and are not rewarded in, the current incentive schemes for economists. In microeconomics, at least there is an abundance of good data, so people who are good at measuring and describing things can succeed. But in macro there is not much data, so most of the rewards are for the mathematics, not the empirics. The single easiest way to make a mark in a modern macro paper is to solve a problem that is really, really hard mathematically. Even if it is not that relevant to anything, it is seen as a sign that the author has “impressive skills,” which is enough to get a job — and even tenure sometimes — at top universities.
- http://knowledge.wharton.upenn.edu/article.cfm?articleid=2234: "Why Economists Failed to Predict the Financial Crisis"
- Time magazine has kindly included me in its annual list of The 100 Most Influential People in the World. I do not know if I deserve to be in such a list as there are so many others who influence so much of our world. But I certainly recognize that there were a small but significant number of economists, thinkers and analysts who – early on – predicted many of the risks and vulnerabilities that eventually led to this crisis. In many ways I simply connected the dot in these different strands of thinking and warnings. Among a few others Robert Shiller was one of the earliest ones to study in detail and warn about a housing bubble; Kenneth Rogoff and a few other economists warned early on about the unsustainability of the US current account deficits and of the global imbalances; Raghu Rajan presented one of the earliest and sharpest analyses of the agency problems and incentive distortions deriving from compensation schemes in financial institutions; Nassim Taleb and a few other finance scholars stressed the risk of fat tail extreme events in financial markets; Paul Krugman – who received his Nobel for his trade contributions – was the father of currency and financial crisis theories in international macro as at least three generations of currency crisis models were developed from his seminal work; Stephen Roach, David Rosenberg and a few other financial sector analysts warned about the shopped-out, saving-less, bubble-addict and debt-burdened US consumer ; Niall Ferguson provided vivid comparisons between historical episodes of financial crises and current vulnerabilities; Hyun Shin and other scholars in academia provided early modeling of illiquidity and of the perverse effects of leverage during asset bubbles; William White and his colleagues at the BIS were among the first – following the scholarship of Hyman Minsky – to analyze how the “Great Moderation” may paradoxically lead to “Financial Instability”, asset and credit bubbles and financial crises; Gillian Tett and a few other journalists at the Financial Times provided early clear explanations of the arcane complexity of credit derivatives and structured finance and of the systemic risks deriving from these new exotic financial instruments; dozen of serious and deep thinking scholars in academia modeled analytically – and tested empirically - the various aspects of systemic financial crises and the interactions between currency crises, systemic banking crises, systemic corporate and household debt crises and sovereign debt crises. RGE - The thinkers who predicted early on many aspects of this financial crisis
- The World Finance Crisis & the American Mission - The New York Review of Books: "The World Finance Crisis & the American Mission By Robert Skidelsky Fixing Global Finance by Martin Wolf Johns Hopkins University Press"
- The night they reread Minsky - Paul Krugman Blog - NYTimes.com Brad DeLong offers a neat little model of speculative fluctuations in asset prices, based on the idea that investors gradually switch strategies based on what seems to work for other people: if people buying stocks seem to be doing well, more people move into stocks, driving up prices and making stocks look even more attractive. It’s very close to Shiller’s notion of bubbles as natural Ponzi schemes. And Brad’s version is very much what I was saying in this piece written in 1999 — one I had a lot of fun writing.
- Dani Rodrik's weblog: Phew! It turns out that the man who brought down the world economy studied not finance or economics--but political science! Now my colleagues and I can go out in public again...
- Revisiting Economics 101 Free exchange Economist.com Over the weekend, Greg Mankiw took stock of how the teaching of basic economics will change as a result of the crisis. It is a very exciting time to be teaching and researching in the field, though the introductory courses will probably not change so much. Economics provides a tool kit to think about the world. Basic concepts like supply and demand and how to distribute a fixed amount of resources have not changed. If anything, basic economics will take a harder look at how aspects of the financial system lead to market failure. Perhaps there will be more humility. In the past students have learned economics under the presumption that systematic bank failure, rampant inflation and unsustainable debt were the terrain of developing economies. The developed world, it was thought, understood policy well enough to prevent those things from occurring. American economists probably no longer take that for granted. Many people, even in the field, lost sight of what economics is meant to do, which is provide a framework for thinking about problems rather than forecasting the future. So, Mr Mankiw writes It is fair to say that this crisis caught most economists flat-footed. In the eyes of some people, this forecasting failure is an indictment of the profession. But that is the wrong interpretation. In one way, the current downturn is typical: Most economic slumps take us by surprise. Fluctuations in economic activity are largely unpredictable. Yet this is no reason for embarrassment. Medical experts cannot forecast the emergence of diseases like swine flu and they can’t even be certain what paths the diseases will then take. Some things are just hard to predict. Likewise, students should understand that a good course in economics will not equip them with a crystal ball. Instead, it will allow them to assess the risks and to be ready for surprises. At the very least, classroom discussion will be more dynamic.
- Sounding the Alarm: Update on the Economic Downturn New York Times columnist Bob Herbert called Mishel’s analysis one that shows “the human toll caused by job losses on this vast scale.” (Read Herbert op-ed.) Mishel says “we must reexamine our policies and enact further public investments as stimulus, provide relief to the many families that are and will be struggling, and use government to directly generate jobs in areas where private sector activity is especially weak.”Click to open slide show viewer Read explanatory text by clicking the Notes icon in the viewerDownload original slide show
- Two Views on the Cause of the Global Crisis – Part I Income inequality and speculative investment by the rich and poor in America led to the financial meltdown.
- Global Crisis: How Far to Go? Part I Mistrust over lending grips the globe, but a wiser, more nimble US could emerge from the chaos.
- Global Crisis: How Far to Go? Part II Falling export demand could rattle Asian countries, but most are resilient enough to survive.
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