Showing posts with label Methodology. Show all posts
Showing posts with label Methodology. Show all posts

Friday, February 1, 2013

Teaching Economics

This week I reviewed Meme Wars: The Creative Destruction of Neoclassical Economics (edited by Kalle Lasn and Adbusters) for the LSE Review of Books. (You can read the full review here). Meme Wars styles itself as an alternative ‘Econ 101′ textbook and the core of the book is a collection of short essays that question the ideas and teaching of mainstream, neoclassical economics. Its radical approach (in both design and content) might be off-putting to some, but I'd recommend it - both for experienced economists, as a challenge to think more broadly about underlying assumptions and fundamental questions about the purpose of the discipline - and especially for those who are new to economics, as an introduction to some alternative ways of thinking about the economy. 

While many of the criticisms raised here are already gaining traction within the discipline, for example through the emerging paradigms of ecological, behavioural and complexity economics, Meme Wars is right in complaining that these developments are generally not reflected in the economics taught to undergraduate students. A recent paper (available here) that tracks changes in the content of the bestselling introductory economics textbooks since the onset of the global financial crisis, would appear to confirm this view, i.e. little has changed.

However, that is not to say that 'mainstream' voices in economics are not willing to challenge the status quo. Meme Wars contains contributions from the likes of Joe Stiglitz and George Akerlof, among others. I also recently came across a collection of essays titled What's the Use of Economics? Teaching the Dismal Science After the Crisis edited by Diane Coyle (see here for details), which includes contributions from numerous established names in economics.

The currents of change and debate within economics make this an exciting time to be a part of the discipline. It would be a shame not to share this excitement with those being introduced to the subject for the first time.

Tuesday, October 30, 2012

Expert accountability

The ruling last week by an Italian court that seven scientists were guilty of manslaughter for failing to warn citizens about the threat of a major earthquake in the city of l'Aquila, raises some difficult questions about accountability and ethics in relation to the provision of 'expert' opinion and scientific advice to governments and the wider public. The scientific community and global media have reacted with outrage, comparing the verdict and threat of lengthy jail sentences for the scientists involved with the persecution of Galileo and the burning of witches.

I agree in principle and in spirit with this sense of outrage. The ruling appears to betray a lack of understanding of the inherent uncertainty in any scientific endeavour, which is particularly pronounced when it comes to forecasting future events. Furthermore, putting science on trial in this way threatens to curtail the progress of scientific inquiry generally, and more specifically--in the nearer term--to make the position of those charged with civil protection and disaster prevention, in Italy at least, almost untenable. However, there remains an important point relating to accountability and ethics that appears to have been overlooked amidst all the righteous indignation.

In an excellent article in Nature, Stephen S. Hall outlines the sequence of events that led up to the tragedy. In an extraordinary meeting of the National Commission for the Forecast and Prevention of Major Risks, the seven scientists--who were all members of the Commission--reached the conclusion that an earthquake was "unlikely" (if not impossible). This in turn was interpreted by a government official, speaking at a press conference, as meaning the situation in l'Aquila was "certainly normal" and posed "no danger". The same official further added that the sequence of minor quakes and tremors that had been occurring in the region was in fact "favourable ... because of the continuous discharge of energy".

This interpretation is apparently contrary to the scientific evidence. The same article, by Hall, quotes Thomas Jordan, director of the Southern California Earthquake Center at the University of Southern California in Los Angeles, and chair of the International Commission on Earthquake Forecasting (ICEF), as suggesting that in the aftermath of a medium-sized shock in a seismic swarm (a sequence of tremors), the risk of a major quake can increase anywhere from 100-fold to nearly 1,000-fold in the short term, although the overall probability of a major quake remains relatively low--at around 2%, according to a study of other earthquake-prone zones in Italy (G. Grandori et al. Bull. Seismol. Soc. Am. 78, 1538–1549; 1988), also quoted by Hall.

A 1,000- (or even 100-) fold increase in the probability of a major quake, would have been a very different message for public consumption than the "anaesthetizing" reassurances given to the media at the press conference. Clearly, the most egregious error committed here was in the over-, or indeed mis-interpretation, of the scientific evidence by the government official who spoke to the press. The scientists were--apparently--correct in their assessment that a major quake remained "unlikely", although not impossible. But, was this the best way of characterizing the risks for the general public?

One of the people affected by the L'Aquila earthquake, quoted in Hall's article, admits that he feels "betrayed by science"--"Either they didn't know certain things, which is a problem, or they didn't know how to communicate what they did know, which is also a problem."

It may be that the error here was not in mis-stating the risk, but in not being specific enough about it. There is an understandable reluctance to use statistics, probabilities and scientific terminology in the public communication of scientific evidence. But at times we take this too far. The public is not stupid, and--problems with common misunderstandings in relation to probability notwithstanding--would be better served by the scientific community and public officials avoiding condescending reassurance in favour of the clear presentation of facts.

Is woolly language, such as "unlikely" really any more useful or informative than saying simply "we don't know"? Might the committee have been better to present the available statistical evidence--including details about the changes in probabilities--while acknowledging that the precise timing and location of a major quake is essentially unpredictable?

The advice could have stopped short of ordering a full-scale evacuation--which, on the basis of the best available evidence, would have been unnecessary 98% of the time--and instead, simply presented that evidence, enabling people to make their own informed decisions about what level of risk they were willing to accept.

Returning to the issue of accountability and ethics, to what extent should scientific or other experts be held accountable for the advice they give to governments or to the wider public? In the case of the l'Aquila tragedy, a more relevant question might be; should researchers be held accountable for the way in which their findings are interpreted by policy-makers and, in turn, by the media? Should researchers generally consider how their findings are likely to be interpreted before making them public? This almost certainly places an unreasonable burden on researchers.

And yet--while researchers can't be expected to control how others interpret their findings, a greater effort needs to be made in communicating the science--its achievements and its limitations--directly to the public. With the recent proliferation of sources for news, opinion and analysis, the authority of traditional media outlets and the role of journalists and editors as the gatekeepers of public information, is increasingly being challenged. This presents both a challenge and an opportunity for scientific engagement with a wider audience. It is increasingly difficult for members of the public to distinguish the signal of scientific or expert analysis from (a) noise and (b) intentionally biased or deceitful opinion emanating from thinly disguised lobbyists, portraying themselves as independent 'experts'. On the other hand, the internet enables researchers to disseminate their findings, methods and data without intermediation by journalists or politicians.

The 'science on trial' headlines may sound melodramatic, but scientists from both the social and hard-sciences are right to feel they are being challenged to justify their art as at no other time in living memory. Public confidence in "science"--in its broadest sense--has been undermined by episodes such as the 'climategate' controversy. The discipline of economics, similarly, has been widely criticised for not predicting the financial crisis--and more fundamentally, for persisting with models that appear unable to explain 'real world' phenomena. This critique certainly has some merit, and economics as a discipline is evolving to take account of the lessons from related disciplines, notably psychology, biology and epidemiology. However, it has to be recognised--both by researchers and those who would criticise their efforts--that models, by their very nature, are imperfect simplifications of the world they are trying to explain. One clear responsibility of any researcher, is to think carefully about the domain of validity of the models that they use [PDF], to define their limitations, and to communicate this in an unambiguous and honest way, along with any findings from the research.

Reflecting on the trial of the seismologists, the former president of Italy's National Institute of Geophysics and Volcanology, concludes that "scientists have to shut up". On the contrary, the lesson for scientists from this tragedy and the subsequent trial, is to be more proactive in our engagement with the public.

A good starting point might be the establishment of a voluntary code of ethics for researchers. This would include, for example, a commitment to publish annually a list of all sources of funding for one's research. Furthermore, the code might also contain a commitment to make public not only our research findings but also the data and methodology used (including relevant context, limitations and assumptions). Signing up to this code could be a prerequisite for any government advisers, and could similarly become a useful tool for the media in screening 'expert' commentators.


More generally this code would be based on three fundamental guiding principles; honesty, transparency and humility. Going back to Hall's Nature article, he quotes a man who lost his wife and daughter in the earthquake, lamenting the fact that "the science, on this occasion, was dramatically superficial, and it betrayed the culture of prudence and good sense that our parents taught us on the basis of experience and of the wisdom of the previous generations." Perhaps the greatest lesson from this tragedy is the need for a greater degree of humility when it comes to the predictive powers of even the most sophisticated scientific models. 



Wednesday, August 22, 2012

Scientific theory is always up for grabs

Laurence Kotlikoff (an economist at Boston University ) has written an important op-ed piece on Bloomberg about the politicization of the economics profession: "Economists risk labeling as political hacks". While I agree with the general thrust of the argument, and much of the specifics, I was troubled by the line "Economic theory isn't up for grabs". Below is my response, left as a comment after the original article.

*****

This is an excellent article and you raise some very important points that every economist should be concerned about.

However, in the last section of the piece (titled "Consumption Spree") I think you take the argument a step too far. In particular, I have a problem with the line "Economic theory isn't up for grabs. Economic facts aren't a matter of choice." Here you are doing a disservice to economics by exaggerating its claims to scientific impartiality. No theory exists in a vacuum and empirical "facts" must be interpreted in order for them to have any meaning (this is true even for the "hard" sciences, but especially so for social science such as economics)

The preceding discussion on savings rates provides a perfect illustration of this. You take an existing theory (life cycle savings model) and use it to interpret some empirical facts (savings rates, tax incentives) resulting in an explanation of America's low savings rates. This is all perfectly valid. But it involves the selection of a model - based on a particular world view - and the interpretation of the empirical evidence through the prism of that model.

Your argument sounds convincing - and I have no doubt this is at least part of the explanation for low savings rates. But the reader - and certainly other economists - should be free to agree or disagree with your particular interpretation, and to offer alternatives. Indeed alternative explanations of low savings rates have been offered by people who start with a different model or world view and make a different interpretation of the available evidence.

This is how good science should work. It is always up for grabs.

*****

Thursday, October 6, 2011

Kevin O'Rourke on the importance of Economic History

Excellent post on Irisheconomy.ie by Kevin O'Rourke on the importance of Economic History:

One of the most important things that a bit of history gives you is a sense of the importance of context. A model will work very well in some technological or institutional contexts, but not in others. 
[...]
If the only thing that economic history did was protect us from one-size-fits-all merchants, it would still be worth the price of admission.

 
 

Sunday, January 9, 2011

Tony Judt on Captive Minds

The following is an extract from Tony Judt's essay "Captive Minds" in the NYRB:

Today, we can still hear sputtering echoes of the attempt to reignite the cold war around a crusade against “Islamo-fascism.” But the true mental captivity of our time lies elsewhere. Our contemporary faith in “the market” rigorously tracks its radical nineteenth-century doppelgänger—the unquestioning belief in necessity, progress, and History. Just as the hapless British Labour chancellor in 1929–1931, Philip Snowden, threw up his hands in the face of the Depression and declared that there was no point opposing the ineluctable laws of capitalism, so Europe’s leaders today scuttle into budgetary austerity to appease “the markets.”

But “the market”—like “dialectical materialism”—is just an abstraction: at once ultra-rational (its argument trumps all) and the acme of unreason (it is not open to question). It has its true believers—mediocre thinkers by contrast with the founding fathers, but influential withal; its fellow travelers—who may privately doubt the claims of the dogma but see no alternative to preaching it; and its victims, many of whom in theUS especially have dutifully swallowed their pill and proudly proclaim the virtues of a doctrine whose benefits they will never see.

Above all, the thrall in which an ideology holds a people is best measured by their collective inability to imagine alternatives. We know perfectly well that untrammeled faith in unregulated markets kills: the rigid application of what was until recently the “Washington consensus” in vulnerable developing countries—with its emphasis on tight fiscal policy, privatization, low tariffs, and deregulation—has destroyed millions of livelihoods. Meanwhile, the stringent “commercial terms” on which vital pharmaceuticals are made available has drastically reduced life expectancy in many places. But in Margaret Thatcher’s deathless phrase, “there is no alternative.”

It was in just such terms that communism was presented to its beneficiaries following World War II; and it was because History afforded no apparent alternative to a Communist future that so many of Stalin’s foreign admirers were swept into intellectual captivity. But when Miłosz published The Captive Mind, Western intellectuals were still debating among genuinely competitive social models—whether social democratic, social market, or regulated market variants of liberal capitalism. Today, despite the odd Keynesian protest from below the salt, a consensus reigns.

For Miłosz, “the man of the East cannot take Americans seriously because they have never undergone the experiences that teach men how relative their judgments and thinking habits are.” This is doubtless so and explains the continuing skepticism of the Eastern European in the face of Western innocence. But there is nothing innocent about Western (and Eastern) commentators’ voluntary servitude before the new pan-orthodoxy. Many of them, Ketman-like, know better but prefer not to raise their heads above the parapet. In this sense at least, they have something truly in common with the intellectuals of the Communist age. One hundred years after his birth, fifty-seven years after the publication of his seminal essay, Miłosz’s indictment of the servile intellectual rings truer than ever: “his chief characteristic is his fear of thinking for himself.”