Methodology – Page 23 – artdiamondblog.com

Climate Models Allow “the Modeler to Obtain Almost Any Desired Result”

Integrated assessment models (IAMs) are the commonly-used models that attempt to integrate climate science models with economic effect models. In the passage quoted below, “SCC” stands for “social cost of carbon.”

(p. 870) I have argued that IAMs are of little or no value for evaluating alternative climate change policies and estimating the SCC. On the contrary, an IAM-based analysis suggests a level of knowledge and precision that is nonexistent, and allows the modeler to obtain almost any desired result because key inputs can be chosen arbitrarily.

As I have explained, the physical mechanisms that determine climate sensitivity involve crucial feedback loops, and the parameter values that determine the strength of those feedback loops are largely unknown. When it comes to the impact of climate change, we know even less. IAM damage functions are completely made up, with no theoretical or empirical foundation. They simply reflect common beliefs (which might be wrong) regarding the impact of 2º C or 3º C of warming, and can tell us nothing about what might happen if the temperature increases by 5º C or more. And yet those damage functions are taken seriously when IAMs are used to analyze climate policy. Finally, IAMs tell us nothing about the likelihood and nature of catastrophic outcomes, but it is just such outcomes that matter most for climate change policy. Probably the best we can do at this point is come up with plausible estimates for probabilities and possible impacts of catastrophic outcomes. Doing otherwise is to delude ourselves.

For the full article, see:
Pindyck, Robert S. “Climate Change Policy: What Do the Models Tell Us?” Journal of Economic Literature 51, no. 3 (Sept. 2013): 860-72.

Environmentalists Seek to Silence Those Who Dare to Disagree

(p. A13) Surely, some kind of ending is upon us. Last week climate protesters demanded the silencing of Charles Krauthammer for a Washington Post column that notices uncertainties in the global warming hypothesis. In coming weeks a libel trial gets under way brought by Penn State’s Michael Mann, author of the famed hockey stick, against National Review, the Competitive Enterprise Institute, writer Rand Simberg and roving commentator Mark Steyn for making wisecracks about his climate work. The New York Times runs a cartoon of a climate “denier” being stabbed with an icicle.
These are indications of a political movement turned to defending its self-image as its cause goes down the drain.

For the full commentary, see:
HOLMAN W. JENKINS, JR. “BUSINESS WORLD; Personal Score-Settling Is the New Climate Agenda; The cause of global carbon regulation may be lost, but enemies still can be punished.” The Wall Street Journal (Sat., March 1, 2014): A13.
(Note: the online version of the commentary has the date Feb. 28, 2014, and has the title “BUSINESS WORLD; Jenkins: Personal Score-Settling Is the New Climate Agenda; The cause of global carbon regulation may be lost, but enemies still can be punished.”)

The Krauthammer column that the environmentalists do not want you to read:
Krauthammer, Charles. “The Myth of ‘Settled Science’.” The Washington Post (Fri., Feb. 21, 2014): A19.

Many Important Medical Articles Cannot Be Replicated

The standard scientific method is more fallible, and less logically rigorous, than is generally admitted. One implication is to strengthen the case for allowing patients considerable freedom in choosing their own treatments.

(p. D1) It has been jarring to learn in recent years that a reproducible result may actually be the rarest of birds. Replication, the ability of another lab to reproduce a finding, is the gold standard of science, reassurance that you have discovered something true. But that is getting harder all the time. With the most accessible truths already discovered, what remains are often subtle effects, some so delicate that they can be conjured up only under ideal circumstances, using highly specialized techniques.
Fears that this is resulting in some questionable findings began to emerge in 2005, when Dr. John P. A. Ioannidis, a kind of meta-scientist who researches research, wrote a paper pointedly titled “Why Most Published Research Findings Are False.”
. . .
. . . he published another blockbuster, examining more than a decade’s worth of highly regarded papers — the effect of a daily aspirin on cardiac disease, for example, or the risks of hormone replacement therapy for older women. He found that a large proportion of the conclusions were undermined or contradicted by later studies.
His work was just the beginning. Concern about the problem has reached the point that the journal Nature has assembled an archive, filled with reports and analyses, called Challenges in Irreproducible Research.
Among them is a paper in which C. Glenn Begley, who is chief scientific officer at TetraLogic Pharmaceuticals, described an experience he had while at Amgen, another drug company. He and his colleagues could not replicate 47 of 53 landmark papers about cancer. Some of the results could not be reproduced even with the help of the original scientists working in their own labs.

For the full commentary, see:
GEORGE JOHNSON. “Raw Data; New Truths That Only One Can See.” The New York Times (Tues., JAN. 21, 2014): D1 & D6.
(Note: ellipses added.)
(Note: the online version of the commentary has the date JAN. 20, 2014.)

The first Ioannidis article mentioned above is:
Ioannidis, John P. A. “Why Most Published Research Findings Are False.” PLoS Medicine 2, no. 8 (August 2005): 696-701.

The second Ioannidis article mentioned above is:
Ioannidis, John P. A. “Contradicted and Initially Stronger Effects in Highly Cited Clinical Research.” JAMA 294, no. 2 (July 13, 2005): 218-28.

The Begley article mentioned above is:
Begley, C. Glenn, and Lee M. Ellis. “Drug Development: Raise Standards for Preclinical Cancer Research.” Nature 483, no. 7391 (March 29, 2012): 531-33.

Better to Fail at Solving a Big Problem, than to Succeed at a Minor One?

Source of book image: http://ecx.images-amazon.com/images/I/61s10qMqpxL._SL1400_.jpg

Francis Collins, head of the NIH, discusses a favorite book of 2013:

(p. C6) Taking risks is part of genius, and genius is not immune to bloopers. Mario Livio’s “Brilliant Blunders” leads us through the circumstances that surrounded famous gaffes. . . . Mr. Livio helps us see that such spectacular errors are opportunities rather than setbacks. There’s a lesson for young scientists here. Boldly attacking problems of fundamental significance can have more impact than pursuing precise solutions to minor questions–even if there are a few bungles along the way.

For the full article, see:
“12 Months of Reading; We asked 50 of our friends–from April Bloomfield to Mike Tyson–to name their favorite books of 2013.” The Wall Street Journal (Sat., Dec. 14, 2013): C6 & C9-C12.
(Note: the online version of the article has the date Dec. 13, 2013.)

The book that Collins praises is:
Livio, Mario. Brilliant Blunders: From Darwin to Einstein – Colossal Mistakes by Great Scientists That Changed Our Understanding of Life and the Universe. New York: Simon & Schuster, 2013.

Would Science Progress Faster If It Were Less Academic and More Entrepreneurial?

Source of caption and photo: online version of the NYT article quoted and cited below.

(p. D5) There is Big Science, defined as science that gets the big bucks. There is tried and true science, which, from an adventurous dissident’s point of view, is boldly going where others have gone before but extending the prevailing knowledge by a couple of decimal places (a safe approach for dissertation writers and grant seekers).

Then there is bootstrap science, personified by Gene Shinn, who retired in 2006 after 31 years with the United States Geological Survey and 15 years with a research arm of the Shell Oil Company.
. . .
Without a Ph.D. and often without much financing, Mr. Shinn published more than 120 peer-reviewed papers that helped change many experts’ views on subjects like how coral reefs expand and the underwater formation of limestone. Some of his papers, at odds with established scientific views, were initially rejected, only to be seen later as visionary.
His bootstrap ingredients included boundless curiosity, big ideas — “gee-whiz science,” he calls it — persistence, a sure hand at underwater demolition (dynamite was comparatively easy to come by in those remarkably innocent days) and versatility at improvising core-sampling equipment on tight budgets. The ability to enlist the talents of other scientists, many with doctorates, who shared his love of hands-on field work and his impatience with official rules and permits added to the mix.

For the full review, see:
MICHAEL POLLAK. “BOOKS; Science on His Own Terms.” The New York Times (Tues., November 5, 2013): D5.
(Note: the online version of the review has the date November 4, 2013.)

Book under review:
Shinn, Eugene A. Bootstrap Geologist: My Life in Science. Gainesville, FL: University Press of Florida, 2013.

The Use of Note Cards to Structure Writing

(p. A21) I tell college students that by the time they sit down at the keyboard to write their essays, they should be at least 80 percent done. That’s because “writing” is mostly gathering and structuring ideas.
For what it’s worth, I structure geographically. I organize my notes into different piles on the rug in my living room. Each pile represents a different paragraph in my column. The piles can stretch on for 10 feet to 16 feet, even for a mere 806-word newspaper piece. When “writing,” I just pick up a pile, synthesize the notes into a paragraph, set them aside and move on to the next pile. If the piece isn’t working, I don’t try to repair; I start from scratch with the same topic but an entirely new structure.
The longtime New Yorker writer John McPhee wonderfully described his process in an essay just called “Structure.” For one long article, McPhee organized his notecards on a 32-square-foot piece of plywood. He also describes the common tension between chronology and theme (my advice: go with chronology). His structures are brilliant, but they far too complex for most of us. The key thing is he lets you see how a really fine writer thinks about the core problem of writing, which takes place before the actual writing.

For the full commentary, see:
DAVID BROOKS. “The Sidney Awards, Part 2.” The New York Times (Tues., December 31, 2013): A21. [National Edition]
(Note: the online version of the commentary has the date December 30, 2013.)

The article praised by Brooks is:
McPhee, John. “Structure.” The New Yorker (Jan. 14, 2013): 46-55.

Key to Google: “Both Larry and Sergey Were Montessori Kids”

(p. 121) [Marissa Mayer] conceded that to an outsider, Google’s new-business process might indeed look strange. Google spun out projects like buckshot, blasting a spray and using tools and measurements to see what it hit. And sometimes it did try ideas that seemed ill suited or just plain odd. Finally she burst out with her version of the corporate Rosebud. “You can’t understand Google,” she said, “unless you know that both Larry and Sergey were Montessori kids.”
“Montessori” refers to schools based on the educational philosophy of Maria Montessori, an Italian physician born in 1870 who believed that children should be allowed the freedom to pursue what interested them.
(p. 122) “It’s really ingrained in their personalities,” she said. “To ask their own questions, do their own things. To disrespect authority. Do something because it makes sense, not because some authority figure told you. In Montessori school you go paint because you have something to express or you just want to do it that afternoon, not because the teacher said so. This is really baked into how Larry and Sergey approach problems. They’re always asking ‘Why should it be like that?’ It’s the way their brains were programmed early on.”

Source:
Levy, Steven. In the Plex: How Google Thinks, Works, and Shapes Our Lives. New York: Simon & Schuster, 2011.
(Note: bracketed name added.)

Ignoring Einstein’s Mistakes by Deifying Him, Makes Us Forget His Struggles

Source of book image: http://ecx.images-amazon.com/images/I/41zyL4LVYxL.jpg

(p. A13) Mr. Ohanian finds that four out of five of the seminal papers that Einstein produced in the so-called “miracle year” of 1905, when he was working as a patent inspector in Zurich, were “infested with flaws.”
. . .
. . . he notes Einstein’s errors for a purpose, showing us why his achievement was all the greater for them.
In this Mr. Ohanian provides a useful corrective, for there is a tendency, even today, to deify Einstein and other men of genius, treating them as if they were immortal gods. Einstein himself objected to the practice even as he reveled in his fame. “It is not fair,” he once observed, “to select a few individuals for boundless admiration and to attribute superhuman powers of mind and of character to them.” In doing so, ironically, we make less of the person, not more, forgetting and simplifying their struggle.
. . .
. . . Einstein’s ability to make use of his mistakes as “stepping stones and shortcuts” was central to his success, in Mr. Ohanian’s view. To see Einstein’s wanderings not as the strides of a god-like genius but as the steps and missteps of a man — fallible and imperfect — does not diminish our respect for him but rather enhances it.

For the full review, see:
McMahon, Darrin M. “BOOKSHELF; Great and Imperfect.” The Wall Street Journal (Fri., September 5, 2008): A13.
(Note: ellipses added.)

The book under review is:
Ohanian, Hans C. Einstein’s Mistakes: The Human Failings of Genius. New York: W. W. Norton & Company, 2008.

We Should Disenthrall Ourselves of False Scientific Certainties

Source of book image: http://2.bp.blogspot.com/-ELpfH2bTO7c/Tb53WpKuDxI/AAAAAAAADrE/Zq8BQiiasJc/s640/An+Optimists+Tour+of+the+Future+Cover.jpg

(p. C4) Among the scientific certainties I have had to unlearn: that upbringing strongly shapes your personality; that nurture is the opposite of nature; that dietary fat causes obesity more than dietary carbohydrate; that carbon dioxide has been the main driver of climate change in the past.

I came across a rather good word for this kind of unlearning–“disenthrall”–in Mark Stevenson’s book “An Optimist’s Tour of the Future,” published just this week. Mr. Stevenson borrows it from Abraham Lincoln, whose 1862 message to Congress speaks of disenthralling ourselves of “the dogmas of the quiet past” in order to “think anew.”
Mr. Stevenson’s disenthrallment comes in the course of a series of sharp and fascinating interviews with technological innovators and scientific visionaries. This disenthralls him of the pessimism about the future and nostalgia about the past that he barely realized he had and whose “fingers reach deep into [his] soul.” It eventually turns him into an optimist almost as ludicrously sanguine about the 21st century as I am: “I steadfastly refuse to believe that human society can’t grow, improve and learn; that it can’t embrace change and remake the world better.”
Along the way, Mr. Stevenson is struck by other examples of how the way he thinks and reasons is “in thrall to a world that is passing.” The first of these bad habits is linear thinking about the future. . . .
We expect to see changes coming gradually, but because things like computing power or the cheapness of genome sequencing change exponentially, technologies can go from impossible to cheap quite suddenly and with little warning.

For the full commentary, see:
MATT RIDLEY. “MIND & MATTER; A Key Lesson of Adulthood: The Need to Unlearn.” The Wall Street Journal (Sat., February 5, 2011): C4.
(Note: ellipsis added.)

The book praised by Ridley, in the passages quoted above, is:
Stevenson, Mark. An Optimist’s Tour of the Future: One Curious Man Sets out to Answer “What’s Next?”. New York: Avery, 2011.

Analytical Solutions Require Unrealistic Assumptions that Make Models Useless for Policy

Source of book image: http://www.anderson.ucla.edu/faculty/edward.leamer/images/COVER%209120_jkt_Rev1.jpg

(p. 190) When I was a younger man, I and all of my cohort were apprehensive if we saw Ed Leamer in the audience when we were presenting a paper. His comments were blunt, incisive, and often negative. But what truly terrified us was that he was almost always right. . . .

Leamer has produced a highly original little book, with big insights and lessons for us all. He explores the tension between economics that is mathematically sophisticated and complex but often vacuous, versus economics that may be vague but which is useful and carries a message. It is frankly a remarkable work, full of insights and persuasive arguments that need to be read, debated, and taken seriously.
. . .
(p. 191) But this is no rant of an old guy. Leamer gets very specific about his notions of usefulness versus rigor. A good drum to bang on is Samuelson, an important “mathematizer.” I would strongly encourage all young trade economists and perhaps all graduate students who have been subjected to a traditional international trade course at any level, to read the section on factor-price equalization. This is beautifully done and even exciting and funny at times. As told by Leamer, the young Samuelson excoriates Ohlin for largely dismissing the possibility of factor-price equalization and then presents his (Samuelson’s) “proof” of factor-price equalization. The latter, of course, is a theorem that is mathematically correct given the assumptions, but Ohlin is talking about its usefulness in understanding the world and constructing policy. The factor-price-equalization theorem is indeed a prime example of something that is valid but not useful.
. . .
Yet at the same time, I have thought long and hard about exactly what message should be given to graduate students and assistant professors without much success. The journal publishing business puts a huge premium on rigor over usefulness and few referees or editors are inclined to take the chance inherent in accepting papers that are a bit loose in their analytical or econometric structures, no matter how exciting they might be. If you accept that, then the profession as a whole has to rethink our view of what is an important scientific contribution: I cannot simply tell graduate students to think more broadly and worry less about elegance. Some will of course deny that there is any tension, but I side with Leamer. Over and over again, I hear, read, and/or referee papers (p. 192) where, in order to get an analytical solution to a model, the author has to assume away almost every interesting feature of the problem to the point that the remaining model is uninteresting and uninformative. But that at least qualifies the paper for possible publication in Econometrica, RESTud, or JET.

For the full review, see:
Markusen, James R. “Book Review of Ed Leamer’s the Craft of Economics.” Journal of Economic Literature 51, no. 1 (2013): 190-92.
(Note: ellipses added; italics in original.)

The book under review is:
Leamer, Edward E. The Craft of Economics, Ohlin Lectures. Cambridge, MA: The MIT Press, 2012.

To Avoid Economic Crises We Need to Look at Evidence from Economic History

(p. 1093) Methodologically, the most fundamental and forceful message from the book is that, by ignoring history and the fact that crises remain frequent, recurrent, episodic events–in both rich and poor countries–almost everyone, including researchers and policymakers, made themselves vulnerable to the wishful thinking encapsulated in the book’s title. There is a deeper statistical point here. Crises, and for that matter large recessions and other phenomena that are of first-order interest given their implications for economic activity, occur at quite a low frequency. They are rare events, meaning that they do not occur so frequently, at least for most countries in a short-span time series. Thus recent experience can be an unfaithful guide for scholars and statesmen alike, a good example being the complacent thinking that accompanied the erstwhile Great Moderation of recent decades even as financial pressures built up nationally and internationally. Possibly the most important lesson that readers will take away from this book is that if we are to do better in future, from our policy thinking in the chambers of power to our macroeconometric analyses in academe, (p. 1094) we need to admit the existence of, and come to grips with, a much broader universe of evidence.

For the full review, see:
Taylor, Alan M. “Global Financial Stability and the Lessons of History: A Review of Carmen M. Reinhart and Kenneth S. Rogoff’s This Time Is Different: Eight Centuries of Financial Folly.” Journal of Economic Literature 50, no. 4 (Dec. 2012): 1092-105.
(Note: italics in original.)

The book that Taylor reviews, is:
Reinhart, Carmen M., and Kenneth Rogoff. This Time Is Different: Eight Centuries of Financial Folly. Princeton, NJ: Princeton University Press, 2009.