My Virtual Display
 Random thoughts and notes to self

But Keynes Is Saved by Walras’s Law

Tyler Cowen writes:

Keynes’s General Theory, chapter six: in part ii the bombshell comes, unannounced. Keynes decides that he will declare savings to be a “mere residual.” Consumption and investment alone will determine income and savings is defined as whatever is left over to make the national income equations balance. At the time this was considered by many to be an enormous sleight of hand. The Austrian and Swedish traditions focused on the question of whether planned savings was going to equal planned investment and what happens if not. Keynes has just banished such questions to the woodshed and he has done so by a terminological maneuver.

Whether or not you think that the Austrian and Swedish traditions lead anywhere fruitful, Keynes is on shaky ground here. He is using definitions to favor one causal account of macro over another. That’s not right. You can still make a plausible argument that Keynes is right on empirical grounds that planned savings is not an important force for understanding business cycles. But so far no such empirical argument has been clinched…

I think it is much more than a terminological maneuver. Walras’s law tells us that if one market is out of supply-demand balance, there must be another related market (or markets) that is also out of balance. If planned saving is in excess of planned investment, then planned consumption spending must be less than planned production of consumer goods. You can then follow the inventory adjustment chain–say that as inventories pile up producers cut back on the making of consumption goods. You then try to follow through on what is happening in the money market and you are led to the conclusion that ex ante savings must be destroyed by a process of deleveraging and deflation and… you wind up in the swamp. But you can be rescued from the swamp by recalling Walras’s law, and recognizing that if you just follow the process by which equilibrium is restored in the goods market you will then discover that that process has also restored equilibrium in the flow-of-funds through financial markets.

Keynes’s “terminological maneuver” would not have succeeded if it were not for the fact that Keynes’s theory worked at a level that Wicksell’s or Myrdal’s or Ohlin’s never could.

Dani Rodrik writes:

Self-discovery in practice

It is remarkable to see something in theory work so well in practice. Ricardo Hausmann and I wrote a paper several years ago called “Economic Development as Self-Discovery,” where the idea was that entrepreneurship in a developing country consists of discovering the underlying cost structure–what can and cannot be produced profitably. Initial investors in a new line of economic activity face a great amount of uncertainty, since foreign technology always needs some local adaptation. Plus, their cost discovery soon becomes public knowledge–everyone can observe whether their projects are successful or not–so the social value they generate exceeds their private costs. If they succeed, much of the gains are socialized through entry and emulation, whereas if they fail, they bear the full costs.

Some of the what I have been seeing in Ethiopia is a picture perfect illustration of this process at work. Most notable in this respect is the flower industry, which was started by some courageous entrepreneurs who had observed the success of the industry in nearby Kenya and wondered if it could be made to work in Ethiopia as well. Even though much of the technology is standard, local soil conditions make a lot of difference to the economics of growing flowers, and a whole range of other services–from daily cargo flights to high-quality cardboard packaging–has to be in place before the operation can succeed. To its credit, the Ethiopian government understood the need to subsidize these pioneer firms, through cheap land and tax holidays, and the industry took off. Exports have reached $100 million from zero in just a few years. There are now around 90 flower farms in the country, with latecomers the beneficiary of the tinkering that early investors have undertaken.

A somewhat similar story in an earlier stage of development is playing out in textiles. The largest investment here to date is being undertaken by a foreign firm–a Turkish one as it turns out. Once finished, the operation will be fully integrated from spinning to finished garments and will employ 10,000 workers. All the output will be exported. The Turkish investor is a bit of a risk-lover, by his own admission. He told me that there are many firms in Turkey waiting to see how he will do. If he succeeds, you can be sure a good many will follow in his footsteps.

These are the discovery efforts that have been going on. One must presume that there are many more that could be taking place, but which are not, because it is difficult for pioneers to capture a large enough part of the social surplus they generate, even with the subsidy programs in place.

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Many times, I’ve tried to put together a brief narrative of the causes of World War I, and I invariably find (after the fact) that I’ve left something out. So here’s the latest (and, one would hope, final) attempt…

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There were at least three causes that in confluence led to World War I. Let’s take them one at a time and put them together a little later.

1. Germany unable to feed itself

In his book The Economic Consequences of the Peace (1919), J.M. Keynes cited contemporary estimates suggesting that immediately before the war, Germany had a population of 67 million, while producing enough food to feed about 40 million. Austria was in a qualitatively similar position. This state of affairs was largely caused by the legacy of feudal land ownership, whereby the aristocracy controlled vast amounts of land and extracted substantial rents from them.

2. The gold standard

Under the gold standard, a nation can expand its money supply only as far as its gold stock allows. To expand its gold stock, a nation must have a trade surplus. So expanding the money supply under the gold standard is only possible if a nation has a trade surplus.

Expanding money supply is the quickest way of ending recessions and thus keeping the population gainfully employed and reasonably happy. But under the gold standard, it is only possible if a nation has a trade surplus, so governments, instead of abandoning the gold standard (which was considered the holy cow of economic policy back then), started working on ensuring that their nations always have a trade surplus.

3. The continuing rule of the military aristocracy

All major European countries (with possible exception of Britain) were de-facto ruled by the military aristocracy, educated, if at all, in humanities and the art of war, not in economics (which, having begun in earnest with Marshall’s Principles published in 1890, was barely out of diapers in 1913). Three things were the direct result of this, (1) the ruling class, unable to comprehend the evils of the gold standard, upheld it, (2) the ruling class, being a military elite, actively sought military solutions to economic problems, and (3) the ruling class extracted substantial rents from its vast land holdings, making domestic agriculture prohibitively expensive compared to that of U.S., Canada, Australia, or Argentina.

Put all three together, and what do you get?

To keep the growing urban population employed, you need to expand money supply, which, under the gold standard, is only possible if your country has a trade surplus. To ensure that you have a trade surplus, you begin pressuring other countries into opening their markets for your exports while keeping imports off your domestic market using tariffs or non-tariff barriers. The pressure tactics gradually escalate from diplomacy to the threat or war, until Europe is completely polarized, with all major countries joining one of the two blocs that eventually went to war with each other. Germany, which desperately needs to export manufactures in order to pay for food, is especially aggressive in its attempts to secure export markets for its manufactures. So Europe becomes a powder keg that sits there waiting for a random spark to ignite its explosion. That spark was the assassination of Franz Ferdinand, the heir to the Austrian throne, by a group of Serbian conspirators. Had it not happened, another “cause” (having as little to do with the real causes as the assassination of Franz Ferdinand did) would have been found in a pretty short order…

Paul Krugman writes:

Bernanke’s problem, and ours. This picture shows the target Fed funds rate, the usual tool of monetary policy; the 10-year Treasury rate; and two rates that actually matter to the private sector, the mortgage rate and the rate on Baa-rated corporate bonds. The Fed has had no success in reducing mortgage rates, and corporate borrowing costs have gone up, not down. Add in falling expectations of inflation, and in real terms monetary policy has gotten tighter, not easier.

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As seen on Freakonomics:

Since last Wednesday, the torrent of junk e-mail coursing through the internet has been slowed dramatically, with 40 percent or more of it cut off at the source.

The source of all that spam? San Jose, California. That’s where a group of servers responsible for much of the world’s spam had been operating until they were severed from the internet last week.

The servers had controlled some of the world’s biggest botnets, the legions of hijacked personal computers that flood your inbox with ads for male-enhancement drugs.

The shutdown could be a major blow to spammers’ finances. Every day the botnets remain down means revenue lost. But how much revenue?

Nobody knows for sure, but a team of computer scientists at U.C. Berkeley with an ingenious plan recently reported the first-ever hard numbers on the economics of spam.

After taking over part of an existing botnet, the Berkeley team waged its own spam campaign, sending out almost 350 million pieces of junk e-mail over 26 days. By the end of their trial, they had netted a whopping 28 sales. That’s about one response for every 12.5 million e-mails sent, a conversion rate of less than 0.00001 percent.

They estimate the yearly revenue of the botnet they had infiltrated at around $3.5 million (their full paper is available here).

To put that in perspective, spam costs U.S. companies $33 billion a year in lost productivity, according to one estimate, and $100 billion worldwide.

That means it seems likely the spam industry generates far less wealth than it destroys.

But the parasitic scam will remain with us as long as one in every 12 million or so of us buys the product they’ve been spammed for.

So what are the characteristics of the 28 good souls who decide to click on through and make a purchase?

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Paul Krugman writes:

 Everybody’s talking new New Deal these days — and, predictably, the FDR-haters are out in force, with all the usual claims about FDR having actually made the Great Depression worse. (To the right, way back when, FDR was “That Man.” Now Obama is “that one.” Interesting.)

Eric Rauchway is all over this. Basically, the anti-FDR argument on the data is based on (a) considering people employed by the WPA “unemployed” (even though they were getting paid, and building public works that are in use to this day) plus (b) always focusing on 1938 — the year in which the economy suffered a serious setback from the progress of the previous four years.

Let me offer two pictures, beyond what Eric provides, to clarify things.

First, here’s real GDP (in logs) from 1929 to 1941, plus the trend. (That’s to bypass the employment nonsense). You can see that the economy made up a lot of the output gap before the 1938 setback, but by no means all.

Now, you might say that the incomplete recovery shows that “pump-priming”, Keynesian fiscal policy doesn’t work. Except that the New Deal didn’t pursue Keynesian policies. Properly measured, that is, by using the cyclically adjusted deficit, fiscal policy was only modestly expansionary, at least compared with the depth of the slump. Here’s the Cary Brown estimates, from Brad DeLong:

Net stimulus of around 3 percent of GDP — not much, when you’ve got a 42 percent output gap. FDR might have been more of a Keynesian if Keynesian economics had existed — The General Theory wasn’t published until 1936. Note in particular that in 1937-38 FDR was persuaded to do the “responsible” thing and cut back — and that’s what led to the bad year in 1938, which to the WSJ crowd defines the New Deal.

Implications for Obama: be inspired by FDR, but don’t imitate him slavishly. In particular, your economic policy should be bolder, not more cautious.

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TED spread shot to all-time high in October, and then “subsided” to the level of ordinary panic:

Paul Krugman writes:

Really, I don’t want to talk about me when the world is melting down, but I have had a number of requests for an informal explanation of what I got you-know-what for. So here’s an attempt.

It’s really about two related things: the “new trade theory” and the “new economic geography.”

OK, so what was the “old” trade theory? It’s what you probably learned if you took intro economics. Countries are different – they have different levels of productivity in particular industries, they have different resources, and those differences drive trade. Tropical countries grow and export bananas, temperate countries grow and export wheat. Countries with highly educated workers export high-tech goods, countries with less educated workers export shirts and pajamas.

The new trade theory starts with the observation that while this explains a lot of world trade, it also misses a lot. France and Germany sell lots of stuff to each other, even though they have similar climates and resources; so do the United States and Canada. What’s that about?

The answer is that there are many goods that aren’t like wheat or bananas, but are instead like wide-bodied jet aircraft. There are only a few places in which wide-bodied jets are produced, because of the enormous economies of scale – you only want a couple of factories worldwide. Those factories have to be somewhere, and those countries that get the factories export jets, while everyone else imports them.

But who gets the aircraft factories, or the factory producing a specialized kind of machine tool, or the plant producing a particular model of car that selected consumers all over the world want? The answer of new trade theory – and it was a tremendously liberating answer – is that it doesn’t matter. There are many economies-of-scale goods; everyone gets some of them; and the details, which may be largely a story of historical accident, aren’t important.

What matters, instead, is the overall pattern of trade: the broad pattern of what countries produce is determined by things like resources and climate, but there’s a lot of additional specialization due to economies of scale, and there’s much more trade, especially between similar countries, than you would expect from a purely resource-based theory.

You may think all this is obvious, and it is – now. But it was totally not obvious before 1980 or so – except for some prescient quotes from Paul Samuelson, you really can’t find anyone describing trade this way until after the theory had been laid out in mathematical models. The plain English version came later.

And you should bear in mind that economists have been thinking and writing about international trade for a couple of centuries; to come along and say, “Hey, we’ve been missing half the story” was a pretty big thing.

Now, on to geography. A decade after the original new trade stuff, I started thinking about what happens when some (but not all) economic resources, especially labor and capital, can move. In the world of the old trade theory, “factor mobility” was a substitute for trade: if factories and industrial workers can move freely, they’ll spread out to be close to the farmers, and neither food nor manufactured goods will have to be shipped long distances. But in the economies-of-scale world I had been studying, the “centrifugal” effect of widely dispersed resources, which tends to push economic activity into spreading out, would be opposed by the “centripetal” pull of access to large markets, which tend to promote concentration of economic activity.

Think of Henry Ford and his Model T. He could have established many factories, spread across the country, to be close to his customers. Instead, however, he found that it was worth incurring extra shipping costs to achieve the economies of scale of one big factory in Michigan.

And once you’re concentrating production in a limited number of locations, which locations will you choose? Locations where there’s a large market – which will be locations where lots of other producers have also chosen to concentrate their production. If the centripetal forces are strong enough, you’ll get a cumulative process: regions that for historical reason have a head start as centers of production will attract even more producers, becoming the economic “core” while other areas become the “periphery.” Thus for about a century, until the rise of the Sunbelt, the great bulk of U.S. manufacturing was crammed into a fairly narrow belt from New England to the inner Midwest; today, 60 million people live along a narrow stretch of the East Coast. Those 60 million people aren’t there because of the scenery; each of them is there because the other 60 million people are also there.

The same sort of logic explains why particular industries concentrate in certain locations, except that in such cases the logic involves things like a deep labor market for specialized skills and a good market for suppliers of specialized inputs. What determines which industry locates where? Often, accident: Silicon Valley owes its existence in large part to a couple of guys named Hewlett and Packard, who started some stuff in their garage, New York is New York because of a canal that only pleasure boaters use today.

Again, this may seem obvious, and it is now – but it wasn’t before 1991 or so. As with trade, the plain English version was possible only after the mathematical models had been worked out.

You may ask, where’s the policy implication of all this? Actually, the policy morals are fairly subtle – for example new trade theory does suggest a possible role for government interventions, but also suggests bigger gains from trade liberalization. Mainly my work in trade and geography was about understanding the world, not driving a political agenda.

So that’s what it was all about.

Add: Requests for public domain copies of the key papers cited. Here’s the 1980 paper; here’s the 1991 paper. Both pdf.

Great summary, methinks…

…Paul Krugman! Although I must admit that his work on currency crises, in my opinion, was more than a mere footnote to his achievements in integrating trade theory and economic geography. But then again, maybe I am reading too much between the lines of the Nobel Prize Committee backgrounders. At any rate, congratulations to Dr. Krugman!

A question from Askville:

What’s the impact of the Fed’s $500B bailout on real estate and interest rate?

Will my mortgage interest rate drop dramatically in the next few months? (Planning to sell and trade up a bigger home for investment….)

Real estate prices, in spite of the recent drop, are still way out of line with both incomes and rents. As to mortgage interest rate, here’s a long-term picture for you to ponder (this is conventional mortgage rate as reported by Federal Reserve):

As you can see, the current interest rates are still close to historic lows, so I wouldn’t expect a dramatic drop any time soon…