LARS P. SYLL

Oh dear, oh dear, Robert Lucas is talking nonsense – again

In a recent interview Robert Lucas says he “now believe that the evidence on postwar recessions … overwhelmingly supports the dominant importance of real shocks.”

So, according to Lucas, changes in tastes and technologies should be able to explain the main fluctuations in e.g. unemployment that we have seen during the  last six or seven decades.

Let’s look at the facts and see if there is any strong evidence for this allegation. Just to take a couple of examples, let’s look at Sweden and Portugal:

and at the situation in the eurozone:

What shocks to tastes and technologies drove the unemployment rate up and down like this in these countries? Not even a Nobel laureate could in his wildest imagination come up with any warranted and justified explanation solely based on changes in tastes and technologies. Lucas is just making himself ridiculous.

Rational expectations – assuming we know what in fact we never know

In a laboratory experiment run by James Andreoni and Tymofiy Mylovanov and presented here, the researchers induced common probability priors, and then told all participants of the actions taken by the others. Their findings are very interesting, and says something rather profound on the value of the rational expectations hypothesis in standard neoclassical economic models:

We look at choices in round 1, when individuals should still maintain common priors, being indifferent about the true state. Nonetheless, we see that about 20% of the sample erroneously disagrees and favors one point of view. Moreover, while other errors tend to diminish as the experiment progresses, the fraction making this type of error is nearly constant. One may interpret disagreement in this case as evidence of erroneous or nonrational choices.

Next, we look at the final round where information about disagreement is made public and, under common knowledge of rationality, should be sufficient to eliminate disagreement. Here we find that individuals weigh their own information more than twice that of the five others in their group. When we look separately at those who err by disagreeing in round 1, we find that these people weigh their own information more than 10 times that of others, putting virtually no stock in public information. This indicates a different type of error, that is, a failure of some individuals to learn from each other. This error is quite large and for a nontrivial minority of the population.

Setting aside the subjects who make systematic errors, we find that individuals still put 50% more weight on their own information than they do on the information revealed through the actions of others, although this difference is not statistically significant.

So in this experiment there seems to be some irrational idiots who don’t understand that that is exactly what they are. When told that the earth is flat they still adhere to their own beliefs of a circular earth. It is as if people thought that the probability that all others are idiots with irrational beliefs is higher than the probability that the earth is circular.

Now compare these experimental results with rational expectations models, where the world evolves in accordance with fully predetermined models where uncertainty has been reduced to stochastic risk describable by some probabilistic distribution.

The tiny little problem that there is no hard empirical evidence that verifies these models doesn’t seem to bother its protagonists too much. When asked in an interview by George Evans and Seppo Honkapohja (Macroeconomic Dynamics (2005, vol.9, 561-583) if he thought “that differences among people’s models are important aspects of macroeconomic policy debates”, Thomas Sargent replied:

The fact is you simply cannot talk about their differences within the typical rational expectations model. There is a communism of models. All agents within the model, the econometricians, and God share the same model.

One might perhaps find it odd to juxtapose God and people, but I think Leonard Rapping – himself a former rational expectationist – was on the right track (Arjo Klamer, The New Classical Macroeconomics 1984, p 234):

Frankly, I do not think that the rational expectations theorists are in the real world. Their approach is much to abstract.

Building models on rational expectations either means we are Gods or Idiots. Most of us know we are neither. So, God may share Sargent’s model, but it certainly isn’t my model.

Paul Krugman on the most important book ever written in the history of economics

The illusions of conservative economics

Just as I was wondering how to start this review, along came the Sunday New York Times Magazine with a short article by Adam Davidson with the title “Made in Austria: Will Friedrich von Hayek be the Tea Party’s Karl Marx?” One Tea Party activist reported that his group’s goal is to fill Congress with Hayekians. This project is unlikely to go smoothly if the price of admission includes an extensive reading of Hayek’s writings. As Davidson remarks, some of Hayek’s ideas would not go down well at all with the American far right: among them is a willingness to entertain a national health care program, and even a state-provided basic income for the poor.

The source of confusion here is that there was a Good Hayek and a Bad Hayek. The Good Hayek was a serious scholar who was particularly interested in the role of knowledge in the economy (and in the rest of society). Since knowledge—about technological possibilities, about citizens’ preferences, about the interconnections of these, about still more—is inevitably and thoroughly decentralized, the centralization of decisions is bound to generate errors and then fail to correct them. The consequences for society can be calamitous, as the history of central planning confirms. That is where markets come in. All economists know that a system of competitive markets is a remarkably efficient way to aggregate all that knowledge while preserving decentralization.

The Good Hayek also knew that unrestricted laissez-faire is unworkable. It has serious defects: successful actors reach for monopoly power, and some of them succeed in grasping it; better-informed actors can exploit the relatively ignorant, creating an inefficiency in the process; the resulting distribution of income may be grossly unequal and widely perceived as intolerably unfair; industrial market economies have been vulnerable to excessively long episodes of unemployment and underutilized capacity, not accidentally but intrinsically; environmental damage is encouraged as a way of reducing private costs—the list is long. Half of Angus Burgin’s book is about the Good Hayek’s attempts to formulate and to propagate a modified version of laissez-faire that would work better and meet his standards for a liberal society. (Hayek and his friends were never able to settle on a name for this kind of society: “liberal” in the European tradition was associated with bad old Manchester liberalism, and neither “neo-liberal” nor “libertarian” seemed to be satisfactory.)

The Bad Hayek emerged when he aimed to convert a wider public. Then, as often happens, he tended to overreach, and to suggest more than he had legitimately argued. The Road to Serfdom was a popular success but was not a good book. Leaving aside the irrelevant extremes, or even including them, it would be perverse to read the history, as of 1944 or as of now, as suggesting that the standard regulatory interventions in the economy have any inherent tendency to snowball into “serfdom.” The correlations often run the other way. Sixty-five years later, Hayek’s implicit prediction is a failure, rather like Marx’s forecast of the coming “immiserization of the working class.”

Robert Solow

Mainstream macroeconomics – a complete shambles

Simon Wren-Lewis has a piece on his blog on how teaching macroeconomics after the crisis looks:

I was asked the other day how macroeconomics teaching at Oxford had changed as a result of the Great Recession of 2008-9 … [A]lthough the crisis has added material, nothing has really been thrown away as a consequence of what has happened. We have not, either individually or collectively, decided that the Great Recession implies that some chunk of what we used to teach is clearly wrong and should be jettisoned as a result … As Paul Krugman has pointed out many times, recent developments have in many ways been a vindication of the basic Keynesian model that lies at the heart of any undergraduate macro course … The mess we are currently in is due in part to policy makers ignoring this basic macroeconomic analysis.

This is really gobsmacking.

First of all because I find this rather self-congratulatory and complacent attitude unwarranted.

But also – re Krugman – because it, at least to my reading, seems to be in bad accordance with what Krugman has repeatedly said after the finance crisis, e. g. in his speach at the Eastern Economic Association:

One can make excuses for the failure of the economics profession to foresee that the 2008 financial crisis would happen. It’s much harder to make such excuses for much of the profession’s failure to realize that such a thing could happen …

[T]o argue, or even to think about, the possibility that the old evils could manifest themselves in new forms would have been to question the whole basis of decades of policy, not to mention the foundations of a very lucrative industry.

We’ve entered a Dark Age of macroeconomics, in which much of the profession has lost its former knowledge, just as barbarian Europe had lost the knowledge of the Greeks and Romans.

How did all this knowledge get lost? … First, success in academic economics came from publishing “hard” papers — meaning papers that used rigorous and preferably difficult mathematics … Successive cohorts of students were trained only in the newly rigorous version of macro, which had lost touch with the field’s previous intellectual achievements …

Some economists are pushing forward with new macroeconomic models … But as I’ve said, our big problem was not lack of models … The biggest problem we had as a profession wasn’t failure to keep up with a changing world, it was failure to remember what our fathers learned.

And re the policymakers ignorance, I would rather say like Keynes:

Practical men, who believe themselves to be quite exempt from any intellectual influences, are usually the slaves of some defunct economist.

As an appendage I can’t restrain myself (having a Ph. D. in both economics and economic history) from citing Brad DeLong‘s complaint about economists obviously not being able – or wanting – to learn from history:

We economists who are steeped in economic and financial history – and aware of the history of economic thought concerning financial crises and their effects – have reason to be proud of our analyses over the past five years. We understood where we were heading, because we knew where we had been …

Those who said that there would be no downturn, or that recovery would be rapid, or that the economy’s real problems were structural, or that supporting the economy would produce inflation (or high short-term interest rates), or that immediate fiscal austerity would be expansionary were wrong. Not just a little wrong. Completely wrong.

Of course, we historically-minded economists are not surprised that they were wrong. We are, however, surprised at how few of them have marked their beliefs to market in any sense. On the contrary, many of them, their reputations under water, have doubled down on those beliefs, apparently in the hope that events will, for once, break their way, and that people might thus be induced to forget their abysmal forecasting track record.

Occasional links has some similar thoughts on the subject:

It is extraordinary to sit here in the midst of the crisis and read the self-satisfied pronouncements of economists about the state of the discipline …

At the level of teaching, where is the history of the theories and debates that have taken place in macroeconomics since at least the publication of John Maynard Keynes’s General Theory? And what about the theories other than the neoclassical and Keynesian versions of IS/LM—where do they fit into the curriculum?

As far as the theory is concerned, what role does uncertainty play in their models? And how do crises occur endogenously, rather than as the result of some exogenous disturbance in either the real or financial side? And what about the role of inequality in determining the level and rates of growth of prices, output, and employment (not to mention the external sector)? And, finally, what’s the explanation of how alternative economic policies are adopted and implemented, other than as irrational mistakes?

[N]either macroeconomics nor microeconomics is in good shape. They weren’t before the crisis began and they’re not now, in the midst of the Second Great Depression. Both areas need to be fundamentally rethought.

Economics in the crisis remains in crisis.

The line of repentant mainstream neoclassical economists ought to be long, and it’s abolutely outrageous that we haven’t seen even one single prominent economist who has had the courage and integrity to admit that he or she got things completely wrong.

Keynes vs. Hayek on BBC Radio 4

John Maynard Keynes and Friedrich Hayek are regarded as two of the twentieth century’s greatest economists. Modern day followers came together at LSE to debate the ideas of their intellectual heroes. The event was chaired by Paul Mason.