Post Keynesianism in Practice

From the FT the other day:

That Facebook is worth $50bn or Twitter $10bn, is recounted as fact. ... But there are still precious few numbers to analyse and business models are no more proved than for dotcoms a decade ago.

To illustrate the ridiculousness of trying to value these things consider LinkedIn. Its S-1 registration statement (with US regulators) provides rudimentary financial statements from which to model the company. Revenues, operating costs, capital expenditure and depreciation and amortisation schedules are available for the past five years. It is then a hop to forecast earnings before interest, tax, depreciation and amortisation and, thus, future free cash flows. Discount these cash flows (made easier because there is no debt) and you’ve got a valuation.

But who on earth knows what forecasts to make? Private secondary markets supposedly value LinkedIn at $2.5bn-$3bn. To arrive at the bottom of that range requires sales to expand 60, 50 then 40 per cent over the next three years, before tailing off to a terminal growth rate of 3 per cent in 2019. Ebitda as a proportion of revenues has to double to 20 per cent and stay there. ... If sales growth tapers off faster than expected or if systems spending becomes a bottomless pit, you can halve that valuation for starters. But what if LinkedIn’s platform easily copes with millions of new members? Double ebitda margins to 40 per cent and a $5bn company is easily within reach. Who knows? No wonder it’s easier to simply quote the same price tag as everyone else.

Fundamental or Knightian uncertainty tends to get treated as something airy-fairy, as part of the philosophy-of penumbra rather than economics per se. But as this example shows, it's unavoidable in plenty of practical questions. Mainstream models avoid dealing with the problem by assuming that the true probability distribution of all possible future events is always known. But in the real world of business people aren't so silly. As the man says:

The outstanding fact is the extreme precariousness of the basis of knowledge on which our estimates of prospective yield have to be made. Our knowledge of the factors which will govern the yield of an investment some years hence is usually very slight and often negligible. If we speak frankly, we have to admit that our basis of knowledge for estimating the yield ten years hence of a railway, a copper mine, a textile factory, the goodwill of a patent medicine, an Atlantic liner, a building in the City of London amounts to little and sometimes to nothing; or even five years hence. In fact, those who seriously attempt to make any such estimate are often so much in the minority that their behaviour does not govern the market. ...

Investment based on genuine long-term expectation is so difficult to-day as to be scarcely practicable. He who attempts it must surely lead much more laborious days and run greater risks than he who tries to guess better than the crowd how the crowd will behave... It needs more intelligence to defeat the forces of time and our ignorance of the future than to beat the gun.

Economists might not believe in Keynes any more. But business journalists certainly seem to!

Krugman vs. Persaud on China

Over on VoxEU, Avinash Persaud criticizes "otherwise respectable economists" (he doesn't name names, but we know who he means) who blame China's currency peg for contributing to the US current account deficit. "If you listen to the discourse in the US," he writes, "you would believe that a country cannot run a trade surplus unless it manipulates its exchange rate."

Krugman responds:

Avinash Persaud:

The current account includes “hot money” inflows that come under the exchange control restrictions and have ballooned since the China bashers created the belief that the renminbi is a one-way appreciation bet.

No, it doesn’t. The BEA explains:

The U.S. current-account deficit—the combined balances on trade in goods and services, income, and net unilateral current transfers …

I don’t mean to be a snob here, but a commentator who lectures us on “mumbo-jumbo” but can’t be bothered to learn the rudiments of balance-of-payments accounting doesn’t deserve a hearing.

On the narrow point, Krugman is clearly right. But the narrow point isn't really the point. Whether you're looking at the current account or at the trade balance, as Persaud prefers, there are plenty of countries with floating currencies that have imbalances as large (relative to GDP) and as persistent as China's. It's nice for Krugman, really, that Persaud screwed up on the current account definition, since it lets him avoid discussing what would otherwise be a serious problem for him.

So, from someone

Quote of the Day

The always interesting Steve Randy Waldman, in response to Tyler Cowen's argument for a technologically-determined "Great Stagnation":

Rather than a paucity of new technologies, we might be experiencing a breakdown of an older gizmo that economists refer to as “markets”. As our economy tilts away from sectors in which value (however defined) and financial revenue are reliably cojoined, our primary means of orienting our behavior towards valuable activity, individually and collectively, become less and less effective.

The whole piece is very smart. But the specific point that the link between productive activity and claims on the collective product is much more tenuous, and institutionally-determined, than mainstream theory assumes is a very good one that I've been struggling to articulate for a while.

Not, of course, that it's a new one. What's that old line? "The productive forces at the disposal of society no longer tend to further the development of the conditions of bourgeois property; on the contrary, they have become too powerful for these conditions, by which they are fettered... The conditions of bourgeois society are too narrow to comprise the wealth created by them."


EDIT: A couple addenda:

The scenario that Waldman has in mind is a systematic bias in innovations toward labor-saving technologies. In the absence of political-institutional changes that raise labor demand in the public sector, and wages across the board, this will lead to a secular rise in unemployment and decline in wages, which is both politically untenable (in a democracy, anyway) and leads to chronic shortfalls in demand.

But one can imagine this going the other way. If one thinks of the wage share as exogenous, then the same technological bias produces a falling profit rate -- this is the famous Law of the Tendency of the Rate of Profit to Fall. Or from a more Schumpeterian angle [1] there's the idea that the fixed costs associated with capital investments can only be recouped if producers have some monopoly power, which tends to diminish as innovations get diffused. So without major new innovations it's hard for industries with large fixed-capital requirements to remain profitable. In this scenario (can we call it Smithian?), the danger is a secular redistribution of income away from profits, not toward them. (Of course this is quite compatible with increasing technological unemployment, with the winners being a labor aristocracy and the owners of scarce natural resources.) But the point about the very loose articulation between the social division of labor and the incomes produced by the market is the same.

Also, Waldman assumes that causality runs only one way, from the innovations drawn from a set of technological possibilities given by nature, to the demand for and status of labor. This is often a reasonable way to look at things. But not always. Schumpeter, again, for example -- despite the misconception that he believed in cycles driven by the exogenous incidence of major innovations -- thought that there was almost always a backlog of unexploited technologies,a nd that their realization as economic innovations depended on the sociological factors -- the rise of "new men" and "new firms". Within Marxist economics, there's an important tradition that sees labor-saving and deskilling not as accidental consequences of technological progress, but as an active goal in a system based on antagonistic relations of production. A system that did not regard skilled labor as a cost -- and even more importantly, that did not need to ensure that a disproportionate share of the surplus went to the owners of the means of production -- might find itself drawing a very different mix of innovations.

[1] Schumpeter's student Minsky picked up on this point, in a way I hope to return to in a future post.

Stimulus Around the World

Interesting new working paper out from the NBER today, on Net Fiscal Stimulus During the Great Recession. It purports to compare the level of fiscal stimulus across 28 rich and developing countries, with results that are decidely gratifying for a Keynesian.

Purports, I say, because unfortunately their chosen measure of fiscal stance makes it hard to know how seriously to take their results. They look only at final expenditures by government, ignoring both transfers and taxes. While there are certainly contexts in which this is the right approach -- where the alternative would be double-counting with private expenditures -- it's not at all clear that it's right for the questions they are trying to answer. From the stimulus side, in theory one would expect the demand effect of final government purchases to be qualitatively greater than the effect of transfers or tax cuts only if the recipients of the latter don't face credit constraints, so that temporary changes operate only through wealth effects. And while I do think that the importance of credit constraints in the Great Recession may be overstated for businesses, they're clearly very important for households, especially the ones most likely to receive transfers like UI. On the debt burden side, obviously deficits add the same whatever their source. On the other hand, it may well be that changes in final expenditure by government is a good proxy for the fiscal stance in general, and perhaps a better one for discretionary stimulus spending. It would be nice to see the paper redone with other measures of stimulus, but let's tentatively accept their findings. What do they show?

First, as Krugman says, if stimulus didn't work in the US, it's because it wasn't tried. The US ranks 9th from the bottom of the 28 countries in the growth of government spending, and even that is only thanks to spending in 2007-08; taking all levels of government together public consumption and investment didn't rise at all in 2009. Of course we knew that already (And we also knew, as Aizenman and Pasricha seem not to, that the earlier increase was almost all military spending.) But it's useful to see it in comparative perspective.

Second, the most interesting finding, that countries with the biggest increases in public spending did not see any larger increase in real interest rates on public debt, either contemporaneously or in the following year, but they did see faster growth. This means the real debt burden - measured as (r - g) * d, where r is the real interest rate on public debt, g is the real GDP growth rate, and d is the debt-to-GDP ratio - fell in those countries where public spending rose the most. If it holds up, this is obviously a very interesting result.

Finally, there's a point they don't make. They observe, correctly, that the US is far from any objective financial constraint on public spending. And they observe; also correctly, that the most aggressively countercyclical fiscal policy is found in middle-income countries like Korea, in sharp contrast to previous downturns, especially the late 90s. But they don't offer any explanation for this change except a vague suggestion that countries chastened by the Asian crisis got their fiscal houses in order, leaving them plenty of space for stimulus. But that's obviously not right. As they themselves note, there's no correlation between the public debt burden prior to the crisis and the trajectory of government spending over the past few years. As I've pointed out before, what's different in countries like Korea in the period before this crisis compared with the Asian Crisis isn't the fiscal balance, but the external balance. They were running external deficits then, external surpluses this time. That's what created the extra space for stimulus. (Same thing in Europe: public-sector surpluses in Spain and Ireland didn't matter because the countries had big current account deficits. It was the corresponding private liabilities thy ended up on public balance sheets in the crisis and created the pressure for spending reductions.) Which brings me to the punchline: If the US had had a smaller trade deficit with,say, Korea in the past few years, that would have had a negligible direct effect on US demand and there's no reason to believe that it would have created space for more expansionary fiscal policy, since we're using nowhere near the space we have. But it very well might have forced Korea to adopt a more contractionary policy, just as other not-exorbitantly-privileged countries without external surpluses have had to. In that sense, though they certainly don't draw this conclusion, I think this paper supports the view that global imbalances have moderated rather than exacerbated the crisis.

Egypt and Exorbitant Privilege

Interesting article on how Mubarak spent his last days in office:

Hosni Mubarak used the 18 days it took for protesters to topple him to shift his vast wealth into untraceable accounts overseas, Western intelligence sources have said. The former Egyptian president is accused of amassing a fortune of more than £3 billion - although some suggest it could be as much as £40 billion - during his 30 years in power. It is claimed his wealth was tied up in foreign banks, investments, bullion and properties in London, New York, Paris and Beverly Hills. In the knowledge his downfall was imminent, Mr Mubarak is understood to have attempted to place his assets out of reach of potential investigators.

On Friday night Swiss authorities announced they were freezing any assets Mubarak and his family may hold in the country's banks while pressure was growing for the UK to do the same. Mr Mubarak has strong connections to London and it is thought many millions of pounds are stashed in the UK.

But a senior Western intelligence source claimed that Mubarak had begun moving his fortune in recent weeks. "We're aware of some urgent conversations within the Mubarak family about how to save these assets," said the source, "And we think their financial advisers have moved some of the money around. If he had real money in Zurich, it may be gone by now."

Interesting, of course, as a reminder of what it means, practically, to be "our son of a bitch." But also interesting, if you're an economist, for the light it throws on another exorbitant privilege -- that of the dollar.

This is the empirically well-established fact that US assets abroad consistently earn higher returns than foreign assets in the US. This differential is an important pillar of the continued (and, for my money, likely to continue for some time) role of the dollar as a reserve currency: Even large US current account deficits don't lead to cumulating interest payments abroad. But why foreign investors in the US get such comparatively low returns -- in one year in the late '90s the total return on foreign assets in the US was actually negative -- remains a bit of a mystery.

Seems to me the Mubarak story points toward (part of) the answer. I have no idea how realistic the higher figure for his fortune is, but it's a big number -- roughly equivalent to a year's worth of Egyptian imports. [1] And of course Mubarak presumably isn't the only Egyptian whose bank balance might not go over well in Tahrir Square. For these "foreign investors", the chance of holding onto their assets when the people they were stolen from ask for them back, has got to be a major component of expected return. And by and large, that means keeping them in forms denominated in dollars. Along with central banks reserves, I reckon this is going to be a substantial portion of net demand for US assets that is relatively insensitive to yield. Enough to explain a significant part of the lower return on foreigners' assets here? I don't know. Could be. But the bigger point is, reserve currency is a political status. I haven't read Barry Eichengreen's new book yet -- it's in the pile on my desk -- but hopefully the Mubaraks of the world will get a central role in his story.


[1] It would be better to compare it to the country's total stock of foreign assets, but I don't know where to find that number for Egypt.

Microfoundations, Again

Sartre has a wonderful bit in the War Diaries about his childhood discovery of atheism:

One day at La Rochelle, while waiting for the Machado girls who used to keep me company every morning on my way to the lycee, I grew impatient with their lateness and, to while away the time, decided to think about God. "Well," I said, "he doesn't exist." It was something authentically self-evident, although I have no idea any more what it was based on. And then it was over and done with...

Similarly with microfoundations: First of all, they don't exist. But this rather important point tends to get lost sight of when we follow the conceptual questions too far out into the weeds.

Yes, your textbook announces that "Nothing appears in this book that is not based on explicit microfoundations." But then 15 pages later, you find that "We assume that all individuals in the economy are identical," and that these identical individuals have intertemporally-additive preferences. How is this representative agent aggregated up from a market composed of many individuals with differing preferences? It's not. And in general, it can't be. As Sonnenschein, Mantel and Debreu showed decades ago, there is no mathematical way to consistently aggregate a set of individual demand functions into a well-behaved aggregate demand function, let alone one consistent with temporally additive preferences. So let's say we are interested in the relationship between aggregate income and consumption. The old Keynesian (or structuralist) approach is to stipulate a relationship like C = cY, where c < 1 in the short run and approaches 1 over longer horizons; while the modern approach is to derive the relationship explicitly from a representative agent maximizing utility intertemporally. But since there's no way to get that representative agent by aggregating heterogeneous individuals -- and since even the representative agent approach doesn't produce sensible results unless we impose restrictive conditions on its preferences -- there is no sense in which the latter is any more microfounded than the former.

So if the representative agent can't actually be derived from any model of individual behavior, why is it used? The Obstfeld and Rogoff book I quoted before at least engages the question; it considers various answers before concluding that "Fundamentally," a more general approach "would yield few concrete behavioral predictions." Which is really a pretty damning admission of defeat for the microfoundations approach. Microeconomics doesn't tell us anything about what to expect at a macro level, so macroeconomics has to be based on observations of macro phenomena; the "microfoundations" are bolted on afterward.

None of this is at all original. If Cosma Shalizi and Daniel Davies didn't explicitly say this, it's because they assume anyone interested in this debate knows it already. Why the particular mathematical formalism misleadingly called microfoundations has such a hold on the imagination of economists is a good question, for which I don't have a good answer. But the unbridgeable gap between our supposed individual-level theory of economic behavior and the questions addressed by macroeconomics is worth keeping in mind before we get too carried away with discussions of principle.