Productivity Pessimism

I'm hoping I'll have a chance to read Robert Gordon's new book soon, though one of the ironies of being a college professor is that the job doesn't seem to leave much time to read.  Fortunately, Gordon presents a condensed version of the argument in a recent Bloomberg View column, where he explains that he doesn't expect a return to the rapid productivity growth of the mid-20th century.  He writes:

The 1920-70 expansion grew out of the second industrial revolution, when fossil fuels, the internal-combustion engine, advanced metals and factory automation came together to produce electric lighting, indoor plumbing, home appliances, motor vehicles, air travel, air conditioning, television and much longer life expectancy.

The "third industrial revolution" - computers and the internet - is less significant, in his view:

Although revolutionary, the Internet's effects were limited when compared with the second industrial revolution, which changed everything. The former had little effect on purchases of food, clothing, cars, furniture, fuel and appliances. A pedicure is a pedicure whether the customer is reading a magazine or surfing the web on a smartphone. Computers aren't everywhere: We don’t eat, wear or drive them to work. We don't let them cut our hair. We live in dwellings that have appliances much like those of the 1950s and we drive in motor vehicles that perform the same functions as in the 1950s, albeit with more convenience and safety.

Our main measure of technological progress is total factor productivity (tfp) growth, which is sometimes called the "Solow residual" because it is calculated as a leftover, by subtracting from output growth the portions that can be explained by changes in capital and labor.  That is, it is the growth that would occur even if there was no change in the factors of production.

Turning points in tfp growth can be hard to identify because the data are somewhat volatile from year-to-year and have a cyclical component.  With hindsight, economists identified a productivity slowdown around 1973 and a resurgence - with information technology playing a leading role - in the mid-1990s.  However, tfp growth has generally been weak since 2005, raising the question of whether the IT-led productivity boom is over.

Data: Bureau of Labor Statistics

This San Francisco Fed Letter from last year discusses some of the reasons for the productivity slowdown.  Gordon's book was the subject of an Eduardo Porter column and a Paul Krugman review.

Update (2/25): In an interview with Ezra Klein, Bill Gates argues against Gordon's view.

China and the Solow Model

Last month, just before China let its currency deprecate and its stock market crashed, the San Francisco Fed published a nice Economic Letter by Zheng Liu, "Is China's Growth Miracle Over?"

China's rapid, but decelerating, growth is broadly consistent with the implications of the classic Solow growth model we teach our intermediate macroeconomics students.  This model predicts that low-income countries should grow quickly, but growth will slow down as they approach the leading countries, whose per-capita growth is constrained by the rate of technological progress. That is, there should be "convergence" in per capita GDP.

As this chart from the letter shows, China is following a similar path to Korea and Japan.

The basic intuition from the model comes from the idea of diminishing marginal product of capital - i.e., where capital (machinery and equipment) is scarce, the increase in output from adding an additional unit is greater than where it is already abundant.  This diagram of output per capita (y) as a function of capital per capita (k) illustrates,

where the slope is the marginal product of capital (MPk).

The idea can be extended to include "human capital" (i.e., knowledge and skills), as Mankiw, Romer and Weil did in a 1992 paper.

While the Solow model gets the broad contours of the growth experiences of Korea, Japan and (it seems so far) China correct (and does pretty well for the US as well), it does miss a couple of big things:

(1) A diminishing marginal product of capital implies that the financial rewards to investing in a low income country should be vastly higher than in high-income countries.  In a world where people can invest across borders, this implies a huge incentives for financial flows from high-income to low-income countries, but we do not observe such large net flows.  This was the puzzle Robert Lucas noted in a 1990 paper.

(2) While the experiences of some low-income countries is consistent with the convergence hypothesis; in many cases, low-income countries have fallen further behind (or, as Lant Pritchett wrote, "Divergence, Big Time.").  From the standpoint of the Solow model, growth "miracles" like those of Korea are to be expected, and the real puzzle is the fact the failure of so many countries to converge.

As Moses Abramovitz pointed out in 1986, it is usually a subset of the low-income countries that are growing fastest.  This would suggest there are forces for convergence, but something is preventing them from applying everywhere.  Current thinking is that the answer lies in "institutions" - the set of legal rights, culture, and governance which shape the economic environment and incentives for people to take actions within it, including to accumulate capital.

This is where assuming that China will continue to follow in the convergence footsteps of Korea and Japan may be questionable.  While China's institutions have gotten it this far, there are reasons to doubt whether they are appropriate for achieving levels of GDP per capita comparable to Korea, Japan and Europe, as this column by Brad DeLong and this by Eduardo Porter discuss.  That said, the institutions in the US during its late 19th century industrialization were hardly what an economist would recommend (in particular, corruption was rampant), and yet it somehow managed to take over leadership in per capita GDP from Britain.

NPR Visits Keynes' (Sister's) Grandchildren

One of the pleasures of teaching is the opportunity to re-read the articles I assign to my students; one particular favorite that I look forward to each semester is Keynes' essay "Economic Possibilities for Our Grandchildren."  NPR's Planet Money recently did an episode about it, focusing on Keynes' famously incorrect (thus far) prediction of a 15-hour workweek.  Although Keynes had no progeny, they did check in with his sister's grandchildren, as well as Harvard economist Richard Freeman - all of whom seem to be hard workers. I discussed some ideas about why we're not enjoying so much leisure in a post last year.  Tim Harford also has some thoughts on his blog.

The prediction about leisure was part of Keynes' more general forecast that economic growth would solve the "economic problem" of scarcity (and his guess about the rate of growth was pretty accurate), and speculation about the social change that would result.  In a similar spirit, in his Bloomberg column, Noah Smith suggested that a post-scarcity world might be like Star Trek: The Next Generation.  He concludes:

In other words, the rise of new technology means that all the economic questions will change. Instead of a world defined by scarcity, we will live in a world defined by self-expression. We will be able to decide the kind of people that we want to be, and the kind of lives we want to live, instead of having the world decide for us. The Star Trek utopia will free us from the fetters of the dismal science.

Or, as Keynes put it in 1930:

Thus for the first time since his creation man will be faced with his real, his permanent problem- how to use his freedom from pressing economic cares, how to occupy the leisure, which science and compound interest will have won for him, to live wisely and agreeably and well.

TFP: Three Episodes or Four?

Zachary Goldfarb reports that this was CEA Chair Jason Furman's favorite chart from the latest Economic Report of the President:

That shows total factor productivity growth (TFP, though some call it "multifactor") which is a measure of technological progress calculated as a residual: the part of output growth that cannot be explained by increases in factors of production (capital and labor).  Another way to think of it is that it is the growth that would occur even if the amount of machinery and equipment as well as labor stayed the same.  The CEA's report explains it quite nicely starting on p. 181.

Technological progress is the key determinant of long run living standards, so if the trend of technological progress has risen after its slump in the 1970's and 80's, its a big deal (and a bigger deal than many of the short-run cyclical issues we tend to obsess over).

The CEA's chart shows 15-year averages which smooths out the year-to-year volatility in TFP growth.  This is sensible because it its hard to discern the long-run trends that the concept is meant to help us understand.  The average TFP growth rate can be split into three eras:

• 1949-1973 -- 1.9%
• 1974-1995 -- 0.4%
• 1996-2012 -- 1.1%

That is, productivity growth has risen about halfway back to its "postwar golden age" level since the mid-1990's.  While identifying breaks in a series like this can be tricky, there does seem to be consensus that there was a slowdown in the mid-1970's and a resurgence in the mid-1990's.

However, the results are somewhat different than what I presented to my macroeconomics students a few weeks ago.  This is a chart made from the BLS' Historical Multifactor Productivity Measures for the private non-farm business sector (which I believe is the same data the CEA used).

The gray line is the actual annual growth (you can see why it helps to average out some of the volatility) and the red line is the centered 15-year average (i.e., the same as the CEA's graph).  However, the CEA's method of averaging means that their graph stops in 2005. The years since then have not been good ones for TFP.  Since their data point for 2005 is an average over the years 1998-2012, the CEA is not ignoring the bad news, but they are lumping it in together with some good years (the late 1990's and early 2000's).

The dashed lines in the chart above illustrate an alternative, less optimistic way of interpreting the same data by breaking it down into four eras instead of three:

• 1949-1973 -- 1.9%
• 1974-1995 -- 0.4%
• 1996-2005 -- 1.6%
• 2006-2012 -- 0.5% 

This would be consistent with a brief 'boom', perhaps attributable to information technology and the internet, in 1996-2005, but one that is already exhausted.  That is the view that Robert Gordon took in this NBER working paper (and recent update).

Identification of trends in short periods of volatile data is inherently uncertain, and it may be sensible to think the reduction in TFP growth over the past several years is largely the artifact of cyclical factors.  That seems to be, implicitly, the CEA's view (and Ben Bernanke also has argued for a more optimistic interpretation of long-run prospects).  Whether they're right or Gordon is will make a huge difference for standards of living a generation or two hence, but, just now, it is too soon to tell.

Bernanke Isn't Neutral on the Long-Run

When I first started teaching intermediate macroeconomics ten years ago, I decided to consider economic growth in the first part of the class.  Partly my reasoning was tactical - its the most mathematically challenging part of the class for many students, so I thought it was good to get them in the habit of working hard and taking it seriously at the start (and the competing claims on students' time tend to be less severe earlier in the semester).  The more important rationale was motivation - at the time we were in the midst of the "great moderation" and it was hard to get students who had never seen a serious recession in their lives excited about learning about things like how the Fed sets interest rates.  That, of course, has changed, and I think starting in with business cycles would be a good way to get the students "hooked" now - its tempting to change, but I've stuck with my strategy of emphasizing growth at the beginning of the semester.

As I noted in a recent post, long-run economic growth is the most important determinant of how living standards change from generation to generation, and why they vary so much from country to country.  The rise in incomes over decades is much bigger than the disruptions due to any business cycle downturn, even relatively large ones like the slump following the 2007-08 financial crisis.  Economic theory says that the main determinant of growth in the long run is technological progress, though we're still a little iffy on explaining how that technological change occurs.

Robert Lucas famously said: "Once you start thinking about economic growth, its hard to think about anything else."  Actually, that's pretty wrong - its very easy to be focused on short-run fluctuations and policy responses to them (and this is really important, and the negative consequences of recessions are understated by representative agent type models that Lucas tends to favor).

Ben Bernanke used his commencement address at Bard College at Simon's Rock as an opportunity to step back from his usual focus on managing short-run fluctuations and talk about economic growth.   His speech acts as a rebuttal of sorts to Robert Gordon and others who are worrying that the benefits of the information technology "revolution" for productivity growth are already petering out.  The core of his response is:

First, innovation, almost by definition, involves ideas that no one has yet had, which means that forecasts of future technological change can be, and often are, wildly wrong. A safe prediction, I think, is that human innovation and creativity will continue; it is part of our very nature. Another prediction, just as safe, is that people will nevertheless continue to forecast the end of innovation. The famous British economist John Maynard Keynes observed as much in the midst of the Great Depression more than 80 years ago. He wrote then, "We are suffering just now from a bad attack of economic pessimism. It is common to hear people say that the epoch of enormous economic progress which characterised the 19th century is over; that the rapid improvement in the standard of life is now going to slow down." Sound familiar? By the way, Keynes argued at that time that such a view was shortsighted and, in characterizing what he called "the economic possibilities for our grandchildren," he predicted that income per person, adjusted for inflation, could rise as much as four to eight times by 2030. His guess looks pretty good; income per person in the United States today is roughly six times what it was in 1930.

Second, not only are scientific and technical innovation themselves inherently hard to predict, so are the long-run practical consequences of innovation for our economy and our daily lives. Indeed, some would say that we are still in the early days of the IT revolution; after all, computing speeds and memory have increased many times over in the 30-plus years since the first personal computers came on the market, and fields like biotechnology are also advancing rapidly. Moreover, even as the basic technologies improve, the commercial applications of these technologies have arguably thus far only scratched the surface. Consider, for example, the potential for IT and biotechnology to improve health care, one of the largest and most important sectors of our economy. A strong case can be made that the modernization of health-care IT systems would lead to better-coordinated, more effective, and less costly patient care than we have today, including greater responsiveness of medical practice to the latest research findings.  Robots, lasers, and other advanced technologies are improving surgical outcomes, and artificial intelligence systems are being used to improve diagnoses and chart courses of treatment. Perhaps even more revolutionary is the trend toward so-called personalized medicine, which would tailor medical treatments for each patient based on information drawn from that individual's genetic code. Taken together, such advances could lead to another jump in life expectancy and improved health at older ages.

Other promising areas for the application of new technologies include the development of cleaner energy--for example, the harnessing of wind, wave, and solar power and the development of electric and hybrid vehicles--as well as potential further advances in communications and robotics. I'm sure that I can't imagine all of the possibilities, but historians of science have commented on our collective tendency to overestimate the short-term effects of new technologies while underestimating their longer-term potential.

Finally, pessimists may be paying too little attention to the strength of the underlying economic and social forces that generate innovation in the modern world. Invention was once the province of the isolated scientist or tinkerer. The transmission of new ideas and the adaptation of the best new insights to commercial uses were slow and erratic. But all of that is changing radically. We live on a planet that is becoming richer and more populous, and in which not only the most advanced economies but also large emerging market nations like China and India increasingly see their economic futures as tied to technological innovation. In that context, the number of trained scientists and engineers is increasing rapidly, as are the resources for research being provided by universities, governments, and the private sector. Moreover, because of the Internet and other advances in communications, collaboration and the exchange of ideas take place at high speed and with little regard for geographic distance. For example, research papers are now disseminated and critiqued almost instantaneously rather than after publication in a journal several years after they are written. And, importantly, as trade and globalization increase the size of the potential market for new products, the possible economic rewards for being first with an innovative product or process are growing rapidly.  In short, both humanity's capacity to innovate and the incentives to innovate are greater today than at any other time in history. 

In typical Bernanke fashion, the whole speech is very nicely done (he must be a fantastic professor).  Another thing I liked about it is that Bernanke also makes a case for liberal arts education:

Well, what does all this have to do with creativity and critical thinking, which is where I started? The history of technological innovation and economic development teaches us that change is the only constant. During your working lives, you will have to reinvent yourselves many times. Success and satisfaction will not come from mastering a fixed body of knowledge but from constant adaptation and creativity in a rapidly changing world. Engaging with and applying new technologies will be a crucial part of that adaptation. Your work here at Simon's Rock, and the intellectual skills, creativity, and imagination that that work has fostered, are the best possible preparation for these challenges. And while I have emphasized technological and scientific advances today, it is important to remember that the arts and humanities facilitate new and creative thinking as well, while helping us to draw meaning that goes beyond the purely material aspects of our lives. 

I'd been thinking of adding Robert Gordon's paper on the "headwinds" facing economic growth to the reading list for next year.  Bernanke's speech will be a nice counterpoint to go with it.

The speech is also discussed by the NYT's Binyamin Appelbaum and Washington Post's Neil Irwin.

The Trend of Things

Amid all our concern about financial crises, zero lower bounds, stimulus packages and the euro, its worth remembering that they are related to a short-term fluctuation (albeit a relatively large one) around a long-run trend, and it is the trend that ultimately determines how well-off people will be in the future.  Or,

The prevailing world depression, the enormous anomaly of unemployment in a world full of wants, the disastrous mistakes we have made, blind us to what is going on under the surface to the true interpretation of the trend of things. For I predict that both of the two opposed errors of pessimism which now make so much noise in the world will be proved wrong in our own time-the pessimism of the revolutionaries who think that things are so bad that nothing can save us but violent change, and the pessimism of the reactionaries who consider the balance of our economic and social life so precarious that we must risk no experiments. 

as J.M. Keynes wrote in "Economic Possibilities for Our Grandchildren" (1931).*

The rise in living standards over time - the long-run growth rate - depends on labor productivity (i.e., output per hour of work).  That, in turn, depends on capital per worker and technological progress (broadly defined as our ability to wring more output from a given amount of capital and labor).  Since capital has diminishing returns, it is really technological progress that ultimately matters.

At his Conversable Economist blog, Tim Taylor notes that growth in per capita real GDP over the past two centuries in the US has been remarkably consistent in the long run.  Using Measuring Worth's series, it looks like this:

[Note: plotting the logarithm means that the slope of the line is proportional to the percentage growth rate; the gridlines at 7.5, 9 and 10.5 correspond to $1800, $8100 and $36300, respectively]**

Technological progress essentially determines the slope, and a seemingly small rate of change, compounded over a few decades, is a big deal - a much bigger deal, measured in output, than the "great recession" (whether output is the right thing to count is another, more complicated, matter). So it may be cause for concern that productivity growth, after picking up in from the mid-1990's through the early 2000's, appears to have slowed again.

Average TFP growth rates, US Private Sector (source: BLS)

1948-73:      1.9%

1973-95:      0.4%

1995-2007:  1.4%

2007-11:      0.4%

The New Yorker's John Cassidy has some interesting musings on why that might be.  The alarming possibility is that the productivity resurgence associated with the internet is petering out already.  However, in the short-run, productivity measurements can be volatile and affected by business cycles, so its we may want to hold off on worrying that the trend has turned down.

*I'd actually started writing this and forgotten to finish it put it aside some time before Niall Ferguson's repellent remarks (that he quickly apologized for) about Keynes not caring about the future because he was childless; "Economic Possibilities" is not only evidence that Keynes cared about the long-run, but that he had considerable insight into the process of long-run growth which anticipated some of the implications of Robert Solow's work in the 1950's.  Though it should be admitted that  Keynes' essay also shows that he wasn't entirely above invoking offensive stereotypes himself.

**If anyone knows of a graphing program that easily does a nice job with log scales, I'd love to hear about it (the ones Excel makes don't come out very well and I'm repeatedly aggravated by trying).

Stiglitz on Singapore

Joseph Stiglitz writes:

Singapore has had the distinction of having prioritized social and economic equity while achieving very high rates of growth over the past 30 years — an example par excellence that inequality is not just a matter of social justice but of economic performance.

Finally, an example of a country that can walk and chew gum at the same time!  Oh, wait...

I'm not really that familiar with Singapore (aside from knowing you can't chew gum there), so I won't comment on the particulars, but its worth noting that the comparison Stiglitz makes of Singapore's growth record to that of the US is a little unfair because Singapore was once - not that long ago - a much poorer country than the US.  Standard growth theory predicts that low-income countries should "converge" (i.e., catch up) to higher income ones.  That means that they'll have higher growth rates.

(Data: World Bank)

That said, many low income countries haven't managed to converge, so Singapore does stand out as a successful example which may provide some useful lessons.

Economic Pessimism in Historical Perspective

US industrial production (log scale), 1790-2011:

From Davis, QJE 2004 (1790-1915); Miron and Romer, JEH 1990 (1916-1918); Federal Reserve, 1919-2011.

J.M. Keynes (Economic Possibilities for Our Grandchildren, 1930):

The prevailing world depression, the enormous anomaly of unemployment in a world full of wants, the disastrous mistakes we have made, blind us to what is going on under the surface - to the true interpretation of things.  For I predict that both of the two opposed errors of pessimism which now make so much noise in the world will be proved wrong in our own time - the pessimism of the revolutionaries who think that things are so bad that nothing can save us but violent change, and the pessimism of the reactionaries who consider the balance of our economic and social life so precarious that we must risk no experiments.

Raising the Speed Limit

At Project Syndicate, Barry Eichengreen writes that one of the Great Depression's lessons is that slumps can be good for productivity growth:

Output expanded robustly after 1933. Between 1933 and 1937, the US economy grew by 8% a year. Between 1938 and 1941, growth averaged more than 10%.

Rapid output growth without equally rapid capital-stock or employment growth must have reflected rapid productivity growth. This is the paradox of the 1930’s. Despite being a period of chronic high unemployment, corporate bankruptcies, and continuing financial difficulties, the 1930’s recorded the fastest productivity growth of any decade in US history.

How could this be? As the economic historian Alexander Field has shown, many firms took the “down time” created by weak demand for their products to reorganize their operations. Factories that had previously used a single centralized power source installed more flexible small electric motors on the shop floor. Railways reorganized their operations to make more efficient use of both rolling stock and workers. More firms established modern personnel-management departments and in-house research labs.

There are hints of firms responding similarly now. General Motors, faced with an existential crisis, has sought to transform its business model. US airlines have used the lull in demand for their services to reorganize both their equipment and personnel, much like the railways in the 1930’s. Firms in both manufacturing and services are adopting new information technologies – today’s analog to small electric motors – to optimize supply chains and quality-management systems.

A similar argument has been made that extensive business restructuring around the time of the 2001 recession contributed to productivity growth in the following years.

Indeed, productivity growth recently has been quite strong:

(Business sector output per hour - Bureau of Labor Statistics)

Eichengreen goes on to argue that policy support is necessary:

But this positive productivity response is not guaranteed. Policymakers must encourage it. Small, innovative firms need enhanced access to credit. Firms need stronger tax incentives for R&D. Productivity growth can be boosted by public investment in infrastructure, as illustrated by the 1930’s examples of the Hoover Dam and the Tennessee Valley Authority.

Which sounds alot like the Obama administration's recent initiatives to increase small-business credit, build more infrastructure and make the R&D tax deduction permanent. While a case can be made for the first two as short-run stimulus, the benefits of the research and development tax credit are almost entirely of the long run variety.

In the long run, higher productivity is good news: it means more output per worker and, therefore, higher average wages. However, it also means less employment is needed for any given level of output, which means the increase in unemployment during the recession was than the decline in output would normally imply (see this previous post).

By increasing potential output, ceteris paribus, productivity growth increases the distance between actual economic activity and the economy's capacity sometimes known as the "output gap." This suggests that even stronger demand growth is necessary to close the gap.

The resurgence of productivity growth in the mid-1990's is one of the factors that allowed the Fed to keep interest rates low and allow unemployment to fall to 4% without igniting inflation (whatever else we say about Alan Greenspan now, he deserves credit for recognizing this early on). If Eichengreen is correct, the "productivity boom-in-waiting" will raise the economy's speed limit, and this is one more reason for the Fed to step on it.

Obama on Africa

In his speech in Ghana last week, President Obama cast his lot with the school of thought that emphasizes the centrality of institutions in development. He said:

Development depends on good governance. That is the ingredient which has been missing in far too many places, for far too long. That's the change that can unlock Africa's potential. And that is a responsibility that can only be met by Africans.

The speech got mostly good marks from Paul Collier, Bill Easterly and Chris Blattman.

Shoot Out at the Aid Corral

I think the message is that foreign aid is cool uptown, but not downtown. Development aid booster Jeffrey Sachs (Columbia) and critic William Easterly (NYU) are at it again, and this time it's personal.... (Dambisa Moyo is in on it too; she used to work at Goldman Sachs, which is downtown... coincidence?).

Mark Thoma has rounded up their exchange at Economist's View, and Easterly summarizes at Aid Watch.

Nancy Birdsall sees common ground beneath all the sturm und drang:

I am with the majority of students of aid who agree with both of them, yes both of them, on one thing they actually agree on: that aid has made a difference in improving people’s lives and that there ought to be more of it. You wouldn’t know that what they disagree about is not whether aid “works” but how aid programs should be designed and implemented – a subject that doesn’t get headlines but matters.

Non-Satiation

Brad DeLong revisits "Economic Possibilities for our Grandchildren" -

Nearly eighty years ago, John Maynard Keynes did the math on economic growth and concluded that within a few generations—by the time his peers' great-grandchildren came of age in, say, the 2000's—the persistent economic problem of too-scarce resources and too-few goods would no longer bedevil a substantial portion of humanity. He was right—even in the midst of our current hard times, he is right.

The current recession may turn into a small depression, and may push global living standards down by five percent for one or two or (we hope not) five years, but that does not erase the gulf between those of us in the globe's middle and upper classes and all human existence prior to the Industrial Revolution. We have reached the frontier of mass material comfort—where we have enough food that we are not painfully hungry, enough clothing that we are not shiveringly cold, enough shelter that we are not distressingly wet, even enough entertainment that we are not bored. We—at least those lucky enough to be in the global middle and upper classes who still cluster around the North Atlantic—have lots and lots of stuff. Our machines and factories have given us the power to get more and more stuff by getting more and more stuff—a self-perpetuating cycle of consumption.

Our goods are not only plentiful but cheap. I am a book addict. Yet even I am fighting hard to spend as great a share of my income on books as Adam Smith did in his day. Back on March 9, 1776 Adam Smith's Inquiry into the Nature and Causes of the Wealth of Nations went on sale for the price of 1.8 pounds sterling at a time when the median family made perhaps 30 pounds a year. That one book (admittedly a big book and an expensive one) cost six percent of the median family's annual income. In the United States today, median family income is $50,000 a year and Smith's Wealth of Nations costs $7.95 at Amazon (in the Bantam Classics edition). The 18th Century British family could buy 17 copies of the Wealth of Nations out of its annual income. The American family in 2009 can buy 6,000 copies: a multiplication factor of 350.

Keynes was right about growth, despite predating the Solow growth model by a quarter-century. Some of his speculations about the social and cultural change that would follow in the wake of the end of scarcity have not panned out (so far, at least). DeLong believes we will never run out of things that we want:

Keynes thought that by today we would have reached a realm of plenty where "We shall once more value ends above means and prefer the good to the useful. We shall honour those who can teach us how to pluck the hour and the day virtuously and well, the delightful people who are capable of taking direct enjoyment in things, the lilies of the field who toil not, neither do they spin."

But no dice. I look around, and all I can say is: not yet, not for a long time to come, and perhaps never. I'm convinced that everyone I know can easily imagine how to spend up to three times their current income usefully and productively. (It is only beyond three times your current spending that people judge others' spending as absurd and wasteful.) And everybody I know finds it very difficult to imagine how people can survive on less than one-third of what they spend—never mind that all of our pre-industrial ancestors did so all the time. There is a point at which we say "enough!" to more oat porridge. But all evidence suggests Keynes was wrong: We are simply not built to ever say "enough!" to stuff in general.

In the Times, a while back, Bob Frank came to a similar conclusion.

My Favorite Econ Goof

Marginal Revolution is soliciting nominations for the most famous mistakes of economics. My personal favorite is William Baumol's 1986 American Economic Review article "Productivity Growth, Convergence, and Welfare: What the Long Run Data Show" (link requires JSTOR subscription). In it, he finds that GDP data for 16 countries over the period 1870-1979 validates the convergence prediction of neoclassical growth models. That is, initially poor countries grow faster than rich ones, thereby catching up over time. Looks good, but as Brad DeLong pointed out in "Productivity Growth, Convergence and Welfare: Comment," (AER, 1988 [JSTOR]) the finding suffers from a selection problem. All of the countries in the sample are wealthy in 1979, so, of course, if they started out poor, they caught up. As a way around, with limited data, DeLong instead chooses a sample based on the initial level of income in 1870. Doing so adds several countries like Portugal and Argentina, that did not converge.Some of the nominees at MR have much more cosmic importance, but this case is a good example of how smart people - not just Baumol, but the editors and referees at AER, too - can make mistakes that seem obvious, but only in retrospect after another smart person points them out.

To be fair, it should be mentioned that Baumol did mention the potential issue in a footnote.

Socratic Solow

Brad DeLong reflects on a semester's teaching with a socratic dialogue on the Solow model; an excerpt:

Akhilleus: So why are you morose then?

Glaukon: Because, looking back over my syllabus this semester, I realized that I spent five full weeks--one third of the semester--teaching them the Solow growth model...

Khelona: It's a fine model...

Glaukon: And yet when the rubber hits the road, it doesn't do us any good. It doesn't tell us anything first-order about the world--aside from post-WWII Japanese convergence from a bouncing-rubble B-29 testfield to a prosperous OECD economy.

Khelona: Actually, I don't think the Solow growth model explains that...

Glaukon: You don't?

Khelona: Post-WWII Japan converged to the OECD norm. And the Solow growth model has some convergence in it--if you start out really poor because your economy's capital stock has been turned into rubble or worse by B-29 strikes, you will grow fast because a low capital stock gives you a high social marginal product of investment and depreciation cannot be a drag on growth if there is no capital to depreciate. But these have always struck me as second- or third-order mechanisms in the story of post-WWII economic growth. Trade. Technology transfer. Institutional reform. The survival of the economic-mobilization components of the fascist Tojo dictatorship. The destruction of the other components of the fascist Tojo dictatorship. The ability of large firms to strike high-productivity bargain with their core workforces by shifting risks onto small-scale producer-suppliers and secondary-sector workers. The neocolonial origins of comparative development--that for Cold War-fighting reasons the U.S. was willing to cut Japan an enormous amount of slack in terms of market access that it was not willing to cut Mexico or Argentina or anyone else outside NATO. You know the story. You know the story better than I do.

Glaukon: Great! So now you've depressed me further--you have gotten me down from one example of the model at work telling us something interesting down to zero....

I also had my students spend quite a bit of time - though not quite a third of the semester - on the Solow model, and I have no regrets. This is partly for the reasons expressed a while back by YouNotSneaky!, who also had the classics on the mind, in a post titled "Socrates would have taught the Solow model":

Socrates thought there were two, maybe three, kinds of people in the world and that you could arrange them in a hierarchy;

1. Those who don't know but think they know.
2. Those who don't know but know they don't know.

and then maybe some lucky ones;

3. Those who know and know they know.

There aren't many people in the 3rd category. But for some reason we always expect our models to move us from the 2nd category to the 3rd. And we're not satisfied if the movement is from the 1st to the 2nd.

The Solow model basically says that "it ain't capital accumulation" which is the cause of sustained growth, it's something else, the magical so called "Solow residual" .....

There've been many people over the years that've concluded that since the Solow model doesn't "explain" growth (because it lumps its major cause into an exogenous residual) it is useless and only an excercise in mathematics.

But people! When you thought you knew (it's capital accumulation!) and then you learn that you don't know (it can't be capital accumulation!) you've learned something just as important and valid as if you've acquired a "positive knowledge"....

Moses Abramowitz called the Solow residual a "measure of our ignorance" - and that is indeed a useful thing. I've posted previously on the joys of growth accounting (measuring the residual).

The Solow model is somewhat unsatisfying because it (i) attributes growth to an exogenous constant and (ii) it does not do a good job of explaining the vast differences in incomes between countries. But it is invaluable as a starting point for teaching economic growth because

• It forces students to really learn some key economic concepts, like:
• the implications of diminishing marginal returns
• the difference between levels and growth rates
• The subsequent research on economic growth - endogenous growth theory and the neoclassical counter-reformation as well as the renewed emphasis on institutions (which admittedly is not really new) - can be understood as attempts to resolve the dissatisfaction due to (i) and (ii).

So while Solow doesn't really answer the questions that we would like growth theory to answer, it is tremendously useful for learning some economics and about how economics works.

The Economics of the Iraq Insurgency

Many countries abundant in natural resources have been development failures. This apparent paradox is sometimes called the "resource curse." In part it is attributable to the opportunities for corruption created by abundant resources and the incentives that exist for diverting effort away from productive activity into fighting - often literally - over the rents associated with resources like oil and diamonds.

The the persistence of the insurgency in Iraq may be another manifestation of the resource curse. The NY Times reports that oil money is fueling the violence:

The sea of oil under Iraq is supposed to rebuild the nation, then make it prosper. But at least one-third, and possibly much more, of the fuel from Iraq’s largest refinery here is diverted to the black market, according to American military officials. Tankers are hijacked, drivers are bribed, papers are forged and meters are manipulated — and some of the earnings go to insurgents who are still killing more than 100 Iraqis a week.

“It’s the money pit of the insurgency,” said Capt. Joe Da Silva, who commands several platoons stationed at the refinery.

Five years after the war in Iraq began, the insurgency remains a lethal force. The steady flow of cash is one reason, even as the American troop buildup and the recruitment of former insurgents to American-backed militias have helped push the number of attacks down to 2005 levels.

In fact, money, far more than jihadist ideology, is a crucial motivation for a majority of Sunni insurgents, according to American officers in some Sunni provinces and other military officials in Iraq who have reviewed detainee surveys and other intelligence on the insurgency....

“It has a great deal more to do with the economy than with ideology,” said one senior American military official, who said that studies of detainees in American custody found that about three-quarters were not committed to the jihadist ideology. “The vast majority have nothing to do with the caliphate and the central ideology of Al Qaeda.”

For more on the resource curse, see this column by Tyler Cowen in the Times last year.

To Strive And Not To Enjoy

In his NY Times column, Bob Frank looks at the link (or lack thereof) between income and happiness. After discussing some of the flaws in how GDP and price indexes are measured, he says:

But there is a much bigger problem, one that challenges the very foundation of the presumed link between per-capita G.D.P. and economic welfare. That’s the assumption, traditional in economic models, that absolute income levels are the primary determinant of individual well-being.

This assumption is contradicted by consistent survey findings that when everyone’s income grows at about the same rate, average levels of happiness remain the same. Yet at any given moment, the pattern is that wealthy people are happier, on average, than poor people. Together, these findings suggest that relative income is a much better predictor of well-being than absolute income.

That we are so concerned with our relative status - that our happiness seems to depend more on how much (or little) we feel we are getting ahead than on how well off we are - suggests we have still not shaken loose of the attitudes that Keynes describes in his 1930 essay "Economic Possibilities For Our Grandchildren." He believed that a set of values that encouraged accumulation of wealth for its own sake was an important ingredient in promoting the increase of capital required for economic growth. However, continued growth would ultimately liberate future generations from the "economic problem" of scarcity and allow humanity to live "wisely, agreeably and well" by a nobler set of principles. But, Keynes warned, the transition would be difficult:

The strenuous purposeful money‑makers may carry all of us along with them into the lap of economic abundance. But it will be those peoples, who can keep alive, and cultivate into a fuller perfection, the art of life itself and do not sell themselves for the means of life, who will be able to enjoy the abundance when it comes.

Yet there is no country and no people, I think, who can look forward to the age of leisure and of abundance without a dread. For we have been trained too long to strive and not to enjoy...

Lin on Institutions and Development

We can count Justin Lin, the new chief economist of the World Bank, among those who believe that institutions are crucial for economic growth. He told the Wall Street Journal:

At the beginning, people put a lot of emphasis on resources, and that’s why we had family-planning policy, not only in China but in other parts of the world. [The thinking was that] The more resources per capita, the wealthier the nation. Later on people thought that natural resources may not be so important, they think that capital and technology are important. Now economists start to understand that for all those things — capital needs to be accumulated, technology needs to be adopted, human capital also needs to be accumulated — you need to understand the incentive, the motivation behind those kind of human choices.

These kind of traditional factors of wealth are just some kind of proximate causes. It’s like you say rich people have a lot of money, but you need to understand why they have a lot of money. Now you need to look into what is the deep cause, the real fundamental cause of development. I think increasingly people now understand that institutions are the most fundamental cause.

Because institutions will shape the incentive structure in an economy, about people’s motivation and willingness to engage in work, lending, accumulation of capital. Now people understand that to understand why a country is performing well or performing poorly, institutions are the key. Fundamentally all economic progress needs to be achieved by people’s effort. We need to understand people’s incentives, and people’s incentives are shaped by the institutions in a country.

Although we recognize institutions’ importance, that institutions matter, from what I see, institutions are an area that requires more research. They are often second-best, they are a choice under a certain kind of constraint. If we do not remove those kinds of constraints, if we want to change the institution, you may jump from the second-best to the third-best. Many interventions did not achieve the intended goal, it’s because they did not really address the cause of those kind of distortions.

It sounds like he is reading his Dani Rodrik, and indeed, Professor Rodrik is pleased.

Helping Africa?

The NY Times reports that President Bush accentuated the positive on his trip to Africa:

“This is a large place with a lot of nations, and no question, everything is not perfect,” Mr. Bush said during a brief visit to Benin before arriving Saturday evening here in the capital of Tanzania. “On the other hand, there’s a lot of great success stories, and the United States is pleased to be involved with those success stories.”

Mr. Bush’s short stay in Benin — just three hours, enough time for an airport news conference with President Thomas Yayi Boni and for Air Force One to refuel — made him the first American president to visit that tiny West African nation. It was on Mr. Bush’s itinerary because it represents the kind of success he wants to highlight — how American aid has helped fight poverty and disease in some of the world’s poorest nations.

The administration considers its aid efforts to be one of its successes. In an interview with the Council on Foreign Relations, Steve Radelet of the Center for Global Development offers a mostly positive assessment of the administration's efforts. The centerpiece is the Millennium Challenge Corporation, a program Bush announced in 2002 - Radelet says:

The Millennium Challenge Corporation (MCC) has evolved into what I think is an imaginative and creative new way to think about foreign assistance. It has done many things well, in terms of how it is thinking about foreign assistance, but it has also been quite slow in getting off the ground and dispersing money. What it has done well is recognizing that not all countries are the same and that we should deliver assistance differently to different countries. It separates out those that are better governed, countries that have made choices toward democracy, toward better governance, and toward better health and education policies. It gives those countries the responsibility to set their priorities and design the programs. This is a huge change and a huge step forward in how we think about foreign assistance, to actually give the recipient countries much more responsibility....

They’ve been very slow to disperse the funds so there haven’t been huge benefits on the ground yet. The African countries that have qualified and have signed compacts include Benin, Cape Verde, Ghana, Lesotho, Madagascar, Mali, Morocco, Mozambique. Those are the African countries that have signed compacts for $3.8 billion, which are beginning to be implemented, but it’s still very early in the day. So far, the MCC has only dispersed $150 million worldwide. So, their disbursements have been slow. It still remains to be seen if the great promise of the MCC turns into reality in terms of real benefits for people on the ground.

The structure of the program represents the growing appreciation by economists (and others) of the importance of institutional factors like governance for development.

Since most people do not realize how small a fraction of our income is spent on foreign aid, it is useful to put it in context: According to the OECD, US "Official Development Assistance" was $23.5 billion in 2006. That's a large amount of money, but it is 0.18% of Gross National Income (aka GNP) and less than 0.9% of federal budget outlays - that is, less than one cent from each tax dollar. This chart breaks down American aid by region and category. Although the US is the largest giver by amount, most rich countries give a higher percentage of their incomes in development aid. In percentage terms, Sweden is the most generous (1.02%), followed by Luxembourg and Norway (both 0.89%). In dollar terms, Britain is #2 at $12.5 bn, followed by Japan at $11.2 bn.

But does it do any good? That is the subject of sometimes heated debate. A good starting point on this issue is Nicholas Kristof's review article in the New York Review of Books. Kristof, who is a NY Times columnist, will be speaking at Miami on Mar. 4.

Globalization and Divergence

The gap between the rich and poor nations has widened over the past two centuries, rather than narrowed as neoclassical growth theory (e.g. the Solow model) predicts. At Vox EU, Oded Galor and Andrew Mountford offer a hypothesis to explain this "great divergence":

[W]e suggest that international trade has played a significant role in the differential timing and pace of the demographic transitions across countries and has been a major determinant of the distribution of world population as well as the 'Great Divergence' in income per capita across countries. International trade has an asymmetrical effect on the evolution of industrial and non-industrial economies: While in the industrial nations the gains from trade have been directed primarily towards investment in education and growth in output per capita, a greater portion of the gains from trade in non-industrial nations has been channelled towards population growth...

The expansion of international trade has enhanced the specialisation of industrial economies in the production of industrial, skilled intensive, goods. The associated rise in the demand for skilled labour has induced a gradual investment in the quality of the population, expediting a demographic transition, stimulating technological progress and further enhancing the comparative advantage of these industrial economies in the production of skilled intensive goods. In non-industrial economies, in contrast, international trade has generated an incentive to specialise in the production of unskilled intensive, non-industrial, goods. The absence of significant demand for human capital has provided limited incentives to invest in the quality of the population and the gains from trade have been utilised primarily for a further increase in the size of the population, rather than the income of the existing population. The demographic transition in these non-industrial economies has been significantly delayed, increasing further their relative abundance of unskilled labour, enhancing their comparative disadvantage in the production of skilled intensive goods and delaying their process of development. This implies that international trade has persistently affected the distribution of population, skills, and technologies in the world economy, and has been a significant force behind the 'Great Divergence' in income per capita across countries...

The "demographic transition" they refer to is the reduction in fertility rates that tends to occur as countries develop. In contrast to neoclassical models, their hypothesis implies that investment in human capital and population growth be treated as endogenous variables - i.e. determined within the model, rather than taken as exogenously given.

Growth Accounting is Useful (and Fun)

Dani Rodrik asks a question that perhaps some of my intermediate macro students are asking - that is, if they've started the problem set (seriously, folks, don't wait until Thursday night) - "What Use is Sources of Growth Accounting?"

I am teaching this stuff this week, and while I enjoy doing it and think it is important for students to know--no World Bank country economic memorandum is apparently complete without a sources-of-growth exercise--I wonder what purpose it really serves....

Aside from all kind of measurement problems, these accounting exercises say nothing about causality, and so are very hard to interpret. Say you found it's 50% efficiency and 50% factor endowments. What conclusion do you draw from it? You could imagine a story where the underlying cause of growth is factor accumulation, with technological upgrading or enhanced allocative efficiency as the by-product. Or you could imagine a story whereby technological change is the driver behind increased accumulation. Both are compatible with the result from accounting decomposition. Indeed, I have yet to see a sources-of-growth decomposition which answers a useful and relevant economic or policy question....

What growth accounting allows us to do is to break down output growth into its component parts. For example, growth in "labor productivity" (output per unit of labor) can be decomposed into "total factor productivity" (technological progress) and contributions from "capital deepening" (increasing the amount of equipment per worker), and sometimes also "labor quality" (changes in the education and experience of the labor force).

One recent example that I found interesting is Jorgenson, Ho and Stiroh's paper "A Retrospective Look at the US Productivity Growth Resurgence" which further sub-divides capital deepening and total factor productivity into information technology (IT) and Non-IT components. Their results indicate that the US "productivity resurgence" since the mid-1990's has two distinct sub-periods:

Robert Solow once said "we see the computers everywhere but in the productivity statistics," (this is the "Solow paradox") but they seem to have finally showed up in a big way in the late 1990's. The decomposition suggests that productivity growth in the late 1990's was an Information Technology story, reflected in the boom in IT investment and in productivity growth in the IT sectors. The second phase of the resurgence appears to have been much more broadly based.

I stumbled on another interesting example writing a problem set for my principles students. I asked them to break the 1974-95 slowdown period into sub-periods:The late 1970's were terrible for TFP (perhaps due to oil shocks, or maybe because we were distracted by "CHiPs") but still saw a respectable contribution from capital deepening, while the later period had decent TFP growth, but didn't get much from capital deepening. That might lend some creedence to the notion that the federal budget deficts that ballooned during that period "crowded out" investment.

Rodrik is right that growth accounting doesn't really explain what causes growth, but it is very useful for telling us where to look. That is, it doesn't really answer questions so much as help us figure out what questions to ask.