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Is Freakonomics Ruining Economics?
Writing in the April 02 issue of the New Republic, Noam Scheiber argues Yes. The article is no screed - it's well informed about economics and the state of the profession. Unfortunately, it's gated but do try find a copy somewhere. This bit gives some of the flavor.
Several years after his paper on schooling, Angrist noticed that the Armed Forces Qualifying Test had been misgraded for a few years in the late '70s. This had opened the doors to thousands of subpar applicants and allowed Angrist to compare the lucky underachievers with the people rejected once the glitch got corrected, thereby isolating the impact of military service on wages. The practical effect was to send the grad students scrambling to find other instances in which life-altering decisions had been handed down incorrectly. In 2000, a Harvard professor named Caroline Hoxby discovered that streams had often formed boundaries to nineteenth-century school districts, so that cities with more streams historically had more school districts, even if some districts had later merged. The discovery allowed Hoxby to show that competition between districts improved schools. It also prompted the Harvard students to wrack their brains for more ways in which arbitrary boundaries had placed similar people in different circumstances.
Every few weeks, when a student would stumble onto some new test-grading error or fatefully drawn boundary--what economists call "instruments"--word of the discovery would rocket through the department. The discoverer would become instantly, if momentarily, famous, like the holder of a winning card at a Bingo hall, and inspiring the same mix of reverence and jealousy. A typical conversation around the snack machine at the National Bureau of Economic Research, where many Harvard students had cubicles, went something like: Hey, did you hear that so-and-so found this crazy example of excess tax refunds in western Manitoba in the early '60s? At which point the other would reply, Uh, no, wow, that's, uh, great, and then scamper back to his desk to brainstorm for some similar quirk of public policy. At an age when most people brood that life is too random and arbitrary, these people's biggest complaint was that it wasn't random and arbitrary enough.
In retrospect, I have come to see this as the moment I realized economics had a cleverness problem. How was it that these students, who had arrived at the country's premier economics department intending to solve the world's most intractable problems--poverty, inequality, unemployment--had ended up facing off in what sometimes felt like an academic parlor game?
I think Scheiber is off in a few ways. First, he conflates methods and questions. It's true that clean identification is often found with quirky experiments but a quirky experiment does not necessarily imply a quirky question. Hoxby's work on education, mentioned above, is asking a big question about the effect of competition on schools. Levitt's work on crime uses quirks in police assignment as do those of his "pale imitators" (like those guys that used terror alert levels to estimate the effectiveness of police on the street. Ha, ha!) but we spend well over 100 billion dollars a year combating crime so it's pretty damn important to know how well police, prisons and punishment work. Scheiber criticizes Emily Oster's work but his criticism has nothing to do with his thesis, Oster's work on AIDS, missing women and so forth is on big questions. It's possible to be clever and to think big.
The second problem is to think that if only people did less Freakonomics they would do more big think economics. If only it were so. The truth is that even today most of economics is a wasteland of boring papers on profoundly uninteresting questions. The choice is not Levitt v. Heckman it's Levitt and Heckman (and many others like Buchanan who neither Levitt nor Heckman might appreciate) versus a huge number of non-entities (many highly paid and famous) who answer trivial questions poorly and do it without even the courtesy of offering some entertainment on the side.
Addendum: Tyler has the first comment.
Posted by Alex Tabarrok on March 28, 2007 at 07:18 AM in Economics | Permalink
Comments
I very much agree with Alex. Here is the post I was writing, when I saw his go up:
Noam Scheiber has a lengthy and interesting piece in The New Republic, "Freaks and Geeks: How Freakonomics is Ruining the Dismal Science."
Maybe someone else wrote the subtitle. I thought the article was a good summary of how Steve Levitt has *improved* the economics profession. The exercise is always a comparative one and I can assure you matters were once worse: too theoretical, too much game theory, and too little interest in the real world. That has all changed. At a bare minimum, the Freakonomics movement ensures that everyone understands incentives and that is not to be taken for granted. Levitt-style economics is contrasted with James Heckman but in reality the two movements have risen together, rather than one displacing the other.
If there is any problem in top economics graduate students, it is not excessive interest in the clever at the expense of substance. It is lack of interest period, lack of breadth, and excessive careerism. There is plenty of room in the profession, and in people's brains, for a bit more Freakonomics.
Posted by: Tyler Cowen at Mar 28, 2007 7:29:18 AM
Economics graduate students should research what they find interesting. If these students are doing quirky topics for the advancement of their career, then I think that's terrible, but it they're doing it because they genuinely want to apply new methods to different, non-economy related, questions, then why stop them?
Posted by: golddog at Mar 28, 2007 8:51:44 AM
I think that his argument also shows a lack of foresight in what the Freakonomics style economics will bring. As many readers of this blog could attest, we had no interest in Economics until we were able to see the fun, quirky and practical side of it. along the way, we learned to appreciate some other aspects, but that would never have happened had it economics remained as it was.
My children, and I suspect the children of many others, will have a much stronger and earlier immersion in econ that I ever did, and the repercussions of that fact won't be felt for years to come, but when it does, it will be clearly discernible.
Posted by: Shmuel at Mar 28, 2007 9:30:08 AM
His article isn't a criticism of economics, it's a criticism of academia in general. Just take his sentence "How was it that these students, who had arrived at the country's premier economics department intending to solve the world's most intractable problems--poverty, inequality, unemployment--had ended up facing off in what sometimes felt like an academic parlor game?", and substitute "economics" and "poverty" with the appropriate words for any another discipline.
And we shouldn't be surprised that a professional journalist looks down on the daily life of a grad student.
Posted by: DK at Mar 28, 2007 9:56:18 AM
The truth is that even today most of economics is a wasteland of boring papers on profoundly uninteresting questions.
An academic economist willing to speak the truth about academic economics. Luv it. My affection for Marginal Revolution has just grown exponentially.
Only thing I would append is:
The truth is that even today most of economics is a wasteland of boring papers on profoundly uninteresting questions intentionally complicated by largely meaningless and masturbatory statistical minutiae.
Posted by: Varangy at Mar 28, 2007 10:25:39 AM
Whether it is the nominal "Levitt" style or "Heckman" style, it is refreshing to see more of a focus on one's identification strategy in empirical work. Too many papers find a relationship between two variables in an equilibrium relationship and claim to have found a structural relationship.
Posted by: MW at Mar 28, 2007 10:43:46 AM
His article isn't a criticism of economics, it's a criticism of academia in general.
I'd say it ends up being a criticism of more than even that-- essentially any situation where people take personal pleasure in what Mr. Scheiber thinks should be serious business, or do something for the "wrong reasons." Politicians enjoy the feeling of power or importance instead of wanting to save the world? Actors or musicians love fame and money instead of their art, or athletes get overpaid instead of playing for the love of the game? Teachers ask for more pay, "proving" that they're motivated by money instead of love of students? It's a moral argument, and an old one, that one's intentions must be morally upstanding and correct (with no hidden motivations) in order to work on problems of moral importance.
The criticism is essentially that it has made the business too fun. There is a point that one should not totally lose sight of the importance of the work. However, I'd at least think that making answering serious questions of importance fun is a good thing, not a bad one, even if it attracts people that Mr. Scheiber thinks aren't motivated correctly to solve those problems.
Posted by: John Thacker at Mar 28, 2007 11:34:26 AM
I took my Ph.D. classes from 85-7 in the "meaningless and masturbatory" style.
We all learned about instrumental variables, and read a few papers using them.
What has changed is that there wasn't a mindset that you should approach interesting, but otherwise poorly addressed, questions by looking for instruments. We were taught to 1) throw our hands in the air and point out that some questions couldn't be answered, and 2) repeat the mantra that separating causality from causation was difficult.
I think any claim - that not doing those two things quite as much is bad - is bizarre and deeply misinformed.
Personally, I'm really curious about the motivation of a reporter so interested in revisiting the "good old days". Perhaps they took this tack because they liked the policy conclusions better in the old days ...
Posted by: Dave Tufte at Mar 28, 2007 11:42:17 AM
In the April 2nd 2007 issue of the New Republic, Noam Scheiber has written a long piece titled "Freaks and Geeks". All academic economists should read this piece because it raises a host of issues concerning where academic economics is going.
Is modern economics "too cute"? Would we, in aggregate, be making more progress on fundamental questions if we stuck to the core issues highlighted in any 1st year graduate sequence at a TOP 20 department?
My mother has called me a sociologist and I haven't been insulted by her implicit claim that my work's questions sometimes wander far from the standard fare served up in a 1st year graduate sequence.
The Scheiber article poses the rhetorical question of whether economics is tipping too far in the direction of being too clever. It hints that "real science" is a time intensive process where researchers work for years to become the master of one very small niche while modern applied micro economists feel no guilt positing theories on any subject even those far from our core training such as whether TV watching causes autism.
Permit me to fight back. Where is the real prestige in modern economics? Structural IO is not a "cute" field. Industrial Organization economists writing down structural models of different industries are being tenured with a single digit number of publications. They are in extremely high demand and the discrete choice tools in these fields have been successfully exported to urban economics and environmental economics.
More and more "cute economists" are moving to business schools where they are tenured in applied micro slots. Such individuals are "free to choose". They are smart enough to pursue structural IO if they had wanted to. It is true that "natural experiments" are fun and relatively easy to do but economists are patient people with rational expectations and have an incentive to recognize that there is a cost of pursuing the "easy path". The New Republic article hints that too many young economists are being "seduced by the dark side" of the easy path.
I wonder if this claim is true. If 25 year old PHD student economists want to become well respected academic economists, and they take a look at the skill set that leading economics departments are hiring in then they have every incentive to pursue the "hard stuff".
The article misses that there is comparative advantage in modern economics. Not everyone aspires to be a structural guy, this is part of the reason that this small elite crew is paid so well. Not everyone has the ability to compete with these guys.
What should become of such clever people who aren't cut out to be formal game theorists or structural IO people? Would Scheiber have them go into consulting? My own preference would be that well trained NBER style applied micro people go "interdisciplinary" and try to work with softer social scientists in other fields to help them estimate more convincing empirical designs for measuring treatment effects and establishing plausible causality results.
Economic theorists continue to command great respect in our field and earn some of
the highest paychecks in St. Louis and its greater vicinity. The incentives are
right in modern economics to keep working on hard problems.
Critics such as Scheiber would need to convince me that there has been a "misallocation" of talent as individual economists choose what problems to work on.
Steve Levitt has achieved the best of both worlds. He has generated new knowledge
on many different subjects and has been able to communicate his findings broadly.
Young people everywhere have an increased interest in economics due to Levitt. Some of these young people will opt into doing game theory and structural IO but only they will make this choice for themselves.
If Levitt had chosen to work on "serious" topics using "serious" methods, would he have made a bigger breakthrough? I can't answer that question but Scheiber seems to be saying that the answer is yes.
My bottom line is a chicago one; "what is the market failure here?" Why isn't the equilibrium in our field a pareto optimum?
For this article to be "important" one must believe in dynamic comparative advantage and extreme duration dependence such that if a Harvard 1st year PHD student spends one day on quirky applied micro (rather than pure theory and econometrics) that this permanently leads him to become a sloppy researcher --- the counter factual here is that this researcher would have become a deeper researcher had she not strayed that one day in her attraction to the "fun easy" stuff.
Posted by: matt kahn at Mar 28, 2007 2:08:02 PM
Of course Heckman himself isn't so fond of Levitt's work.
http://www.minneapolisfed.org/pubs/region/05-06/heckman.cfm
This is what he said:
"With this pleasure, I feel a lot of responsibility as well. In economics there's a trend now to come up with cute papers in an effort to be cited as many times as possible. All the incentives point that way, especially for young professors who seem risk-averse rather than risk-taking after they get tenure. In some quarters of our profession, the level of discussion has sunk to the level of a New Yorker article: coffee-table articles about “cute” topics, papers using “clever” instruments. The authors of these papers are usually unclear about the economic questions they address, the data used to support their conclusions and the econometrics used to justify their estimates. This is a sad development that I hope is a passing fad. Most of this work is without substance, but it makes a short-lived splash and it's easy to do. Many young economists are going for the cute and the clever at the expense of working on hard and important foundational problems."
Posted by: Taggert Brooks at Mar 28, 2007 2:48:09 PM
who had arrived at the country's premier economics department intending to solve the world's most intractable problems--poverty, inequality, unemployment--had ended up facing off in what sometimes felt like an academic parlor game
Looking for input deltas and seeing if the outcome differs from the norm is now a parlor trick?
I would agree with that point if the inputs were unrelated to the outputs (ie "sun spots cycles causing more Critical Lit graduates?") but these seem pretty well thought out -- what I would expect from an economics PhD student.
Posted by: BlogReader at Mar 28, 2007 3:37:26 PM
As the earliest critic of Levitt's most famous theory -- that legalizing abortion cut crime -- please allow me to suggest that the problem with Freakonomics is basically that economists generally don't know enough about the real world to come up with rock solid explanations of non-monetary phenomenon like crime and abortion. For example, when Levitt and Donohue came up with their theory in 1998, they (and the other economists they discussed it with at seminars at elite universities) simply overlooked the existence of the crack wars from 1987 to 1994.
So, when I pointed out in my debate in Slate.com with Levitt in 1999 that the murder rate among the first cohort of 14-17 year olds born after legalization was roughly triple that of the last cohort born before legalization, he faced a difficult professional dilemma. Did he step back and withdraw his most famous theory? Or did he plunge onward denouncing his critics? As we all know, he chose the latter and has since ascended to celebrity and fortune.
Levitt's theory, however, continues to take a terrible beating among his less celebrated economists. For example, Christopher Foote and Christopher Goetz showed in 2005 that his results were based on two technical errors he has made.
Since then, Levitt has brought out a new dataset, but the 2006 analysis of that by Dills and Miron was deeply skeptical.
So, the lessons for economists from the Freakonomics Fiasco are the value of humility and being open to the real world.
Posted by: Steve Sailer at Mar 28, 2007 4:25:18 PM
Like a moth to a flame.
Posted by: goodnessoffit at Mar 28, 2007 4:50:40 PM
An excerpt from the latest paper I've seen on the most famous Freakonomics theory -- that legalizing abortion cut crime.
A Comment on Donohue and Levitt's (2006) Reply to Foote and Goetz (2005)
Angela K. Dills Department of Economics, Clemson University
Jeffrey A. Miron Visiting Professor of Economics, Harvard University April, 2006
Donohue and Levitt (2001) (DLI) consider the hypothesis that U.S. legalization of abortion in the early 1970s caused much of the decline in crime in the 1990s. Foote and Goetz (2006) (FG) show, however, that one key result in DLI contained a coding error; dummies for state-year interactions were inadvertently omitted from the regressions. FG demonstrate that correcting this error, along with estimating the regressions using arrest rates rather than arrest levels, suggests virtually no effect of legalized abortion on crime.
Donohue and Levitt (2006) (DLII) acknowledge the coding error and agree that correcting the mistake and using arrest rates suggests no effect of legalized abortion on crime. DLII argue, however, that use of an improved abortion measure and an instrumental variable revives or even strengthens their original result...
Our conclusion is that the kind of analysis considered in Table VII of DLII does not suggest a quantitatively important effect of legalized abortion on crime. The best case for such an effect is the IV results in columns (6) and (7); these imply that abortion legalization explain 24-25.9% of the 1991-1998 decline in violent crime and 7.1-8.1% of that in property crime. None of these coefficients is statistically significant at conventional levels, however, and the results in column (8) suggest they rely on an implausible mechanism relating abortion to crime.
http://post.economics.harvard.edu/faculty/miron/papers/Comment_on_DL_FG.pdf
Posted by: Steve Sailer at Mar 28, 2007 5:09:35 PM
I was just telling my wife how frustrated I was going to weekly seminars and seeing such uninteresting questions discussed, whose models rest on extremely shaky assumptions. I walk out feeling none-the-wiser, but knowing that this presenter too, has a knack for using an economic question as a lousy pretense for demonstrating her math prowess. Enough to get her an offer for a faculty position, anyway.
I loved your comments, and they could not have been better timed!
Posted by: Tim V at Mar 28, 2007 10:45:24 PM
I know, I'm surprised it took that long.
Posted by: radek at Mar 28, 2007 11:15:54 PM
Freakonomics is to Economics what Entrainment Tonight is to Charlie Rose
Posted by: psamuelson at Mar 29, 2007 12:19:42 AM
Isn't Levitt only following in the path established by Buchanan and Becker in earlier challenges to the social sciences?
Posted by: tjr at Mar 29, 2007 7:37:05 AM
The paper on terror alert levels was interesting, but I wonder why you didn't take up the question whether elevated police presence prevented crime from happening, or merely moved it to a different time and place. I suppose the answer depends on whether car thieves steal as much as they can, or as much as they need, or something in between.
Posted by: Harald Korneliussen at Mar 30, 2007 8:58:52 AM
Most economist are not interested in interesting questions but the statistical "masturbation" or math department wannabes.
One of the major problems is that economists have solved a many of the foundational issues of the science. We get it inflation is bad. Market availability of question drives people to focus on other issues.
The real problem is that departments prefer statistical "masturbation" that gets published somewhere to creative work that might not. That's why people will always continue to focus on those types of questions. Only if you are tenured at U Chicago can you get away with what Levitt has done.
Posted by: cdawg at Apr 1, 2007 11:03:50 PM
Steve - regarding the crack hypothesis. You're saying that crack's wane coincided with the point in time where the individuals from the mid-1970s would've came into criminality. But, your point needs to be stronger than merely that crack waned in the early 1990s - it'd need to be that in New York, California, Alaska, Hawaii and Washington (the five pre-Roe repeal states), the crack epidemic waned ahead of the rest of the country, and that is why Levitt and Donahue picked up this effect in their results. IS that your point - that crack fell in the five repeal states ahead of the rest of the country?
Posted by: Jason Voorhees at Apr 2, 2007 5:42:47 PM
I am absolutely delighted with Noam Scheiber's article. As a recent PhD student from the top-ranked graduate program in the country, I have seen this sort of behavior from fellow grad students more frequently than I would care for.
The first question for many of my colleagues was "Whats a clever instrument?" as opposed to "Whats a good research topic?".
In response to some of the comments left in response to the post: yes, of course, it is obvious that there is a need to find good instruments to "identify" causal effects. but Schreiber's critique is that the emphasis in recent research is much more on cleverness for cleverness' sake rather than "identifying" important questions. and even when the right questions are found, the researcher often cares more about how cute or clever the "exogenous variation" or the instrument is than whether it is truly believable or exogenous.
The profession has become so insular that the insiders beat their chests or pat each others backs upon finding clever - but often, very contrived and unconvincing - ways to answer obvious and often trivial questions while all others are left saying "huh, THIS is what you guys call research?"
It is also telling that the more creative the instruments get, the more literature that piece of work generates as other authors devote their careers to discredit the instrument. Scheiber mentioned Oster's paper to illustrate the above point but many of the other papers he mentioned - such as Hoxby and Angrist and Krueger's work - also generated similar streams of work where subsequent authors devoted large chunks of their time trying to discredit the cute instruments rather than trying to answer the underlying economic question that was first posed in the original papers.
Posted by: Disillusioned_economist at Apr 9, 2007 5:16:01 PM
According to Heckman "... Chicago has been a little disappointing in that it hasn't been more firm in rejecting cute and clever".
So much for academic freedom.
I'm not convinced that poverty, discrimination or whatever are going to be solved with government programs or government funded economic research as Heckman wants everybody to think.
But I would never attempt to "reject" or "suppress" anyone's research, no matter how silly it looks to me. I don't consider myself some kind of God to decide who deserves academic glory or doesn't.
Not that I am fond of the Jerry Seinfeld school of economics "research about nothing" either.
Posted by: I am disappointed too at Apr 9, 2007 10:31:18 PM
1. There are two issues being confused here - one, how much of an economist's work is useful to other economists; and two, how much of it is useful to public / policy setters / journalists. Good work serves one of the two purposes well, great work (which comes very seldom) serves both. To say that economists are involved in useless minutiae is ignoring the first, and to say that we are writing too many "cute", non-rigorous papers that look at applied questions in sociology and public policy (crime, abortion etc) is ignoring the second. I do not know enough empirical economics to judge Levitt from the first viewpoint, but I think he has got some darn good conclusions that serve the second purpose. That alone justifies all the academic and non-academic credit he got, and has been getting.
2. Where Scheiber is on the dot (and duly pointed out by one commenter) is that the incentive system in the profession probably susbstitutes the short term benefits (get a quick, cute paper out) for the longer term, more uncertain, but more socially desirable activity of working hard at one difficult problem for a very long time. (Remember the "central theme" paragraph in the introduction to Freakonomics?) However, this problem plagues every discipline, and, I suppose, every profession even outside academia more or less. So, how could we improve the situation, to design an incentive system that will induce behavior closer to the social optimum? That is best left to some "useless" theorist to figure out.
Posted by: Sourav at Apr 12, 2007 12:38:45 PM
I suppose it has always been so, that theologians succeeded best when their pronouncements supported the kleptocracy in place, and only when that kleptocracy got to drunk on it's own Koolade, and did not have the power it pretended does a new "revolutionary genius" arise, to be taken up by the new kleptocracy.
In the rush of the new social scientific awareness, the kleptocracy itself became aware of the mechanisms, and set out to dominate that process as well, and what had been a drift became a torrent, not just in economics, but everything from news to farming.
The result is so extreme that the quality of the argument can be, and unfortunately often is, judged by the direction of flow, rather than the merits. But those with great "success" are usually better at sourcing funds than advancing knowledge.
Fortunately the Internet is the great equalizer, that good work by a researcher in the backwater of a foreign country can compete with one who has his own television show, if only in the minds of those with the gumption to look.
Only time will tell how badly the Kleptocracy has overstepped. It is certainly already gone beyond its wildest dreams of only a few years ago.
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Posted by: wslmwps at Aug 14, 2007 3:56:00 AM
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