LARS P. SYLL

Chicago economics — the triumph of empty formalism

Vielleicht ist diese Grundperspektive der radikalen Trennung von Form und Gehalt hilfreich, einige zunächst überaus paradoxe Äußerungen von Lucas etwas zu erhellen. Erinnert man sich der Forderungen von Lucas, die Makroökonomik zwingend auf Basis der klassischen Postulate, die Lucas und Sargent (1978) als (a) „Markträumung“ und (b) „Eigennutz“ umrissen hatten, zu errichten, so erstaunt man doch angesichts Passagen wie der folgenden:

“In recent years, the meaning of the term “equilibrium” has undergone such dramatic development that a theorist of the 1930s would not recognize it. It is now routine to describe an economy following a multivariate stochastic process as being “in equilibrium,” by which is meant nothing more than that at each point in time, postulates (a) and (b) above are satisfied. This development, which stemmed mainly from work by K. J. Arrow […] and G. Debreu […], implies that simply to look at any economic time series and conclude that it is a “disequilibrium phenomenon” is a meaningless observation. Indeed, a more likely conjecture […] is that the general hypothesis that a collection of time series describes an economy in competitive equilibrium is without con tent.” (Lucas und Sargent 1978: 58-9)”

Zunächst ist man erstaunt, weil die Argumentation nicht nur kontraintuitiv, sondern geradezu widersinnig erscheint: Wie passt das zusammen, dass Lucas und Sargent einerseits einfordern, jegliche Makrotheorie habe von den Prinzipien „Markträumung bzw. Gleichgewicht“ und „Eigennutz bzw. Optimierung“ auszugehen, wenn sie direkt anschließend konstatieren, dass solche Aussagen inhaltsleer und ohne Bedeutung sind? Die hier gelieferte Verteidigung der Gleichgewichtsannahme „geräumter Märkte“ hat demnach für Lucas gar nichts mit jener alltäglichen Bedeutung zu tun, wonach der Markt für Äpfel geräumt ist, wenn wie beobachten können, dass alle angebotenen Äpfel auch gekauft werden. Markträumung als Konzept ist somit kein Ereignis, dass mit der Realität korrespondiert, sondern ein Modellbaukonzept, mit dem Modellstrukturen erzeugt werden kön nen, die Zeitreihen nachbilden können. Die Begriffe „Markträumung“ und „Eigennutz“ haben eben in diesem Sinne keine empirische, oder reale Bedeutung, wie Lucas und Sargent klar herausstellen, sie dienen nur zur Erzeugung der formalen Struktur des Modells, sie sind jedoch losgelöst von ihrer (anschaulichen) Bedeutung oder Interpretation.

Roberto Cruccolini

In case your German isn’t to rusty, Cruccolini’s dissertation on the development of modern macroeconomics is highly recommended reading.

Some of us have for years been urging economists to pay attention to the ontological foundations of their assumptions and models. Sad to say, economists have not hearkened the appeal — and so modern economics has become increasingly irrelevant to the understanding of the real world.

Within mainstream economics internal validity is still everything and external validity nothing. Why anyone should be interested in that kind of theories and models is beyond imagination. As long as mainstream economists do not come up with any export-licenses for their theories and models to the real world in which we live, they really should not be surprised if people say that this is not science.

Studying mathematics and logics is interesting and fun. It sharpens the mind. In pure mathematics and logics we do not have to worry about external validity. But — economics is not pure mathematics or logics. It’s about society. The real world. Forgetting that, economics is in dire straits.

The scientific method arose as a rejection of the axiomatic method used by the Greeks for scientific methodology. It was this rejection of axiomatics and logical certainty in favour of empirical and observational approach which led to dramatic progress in science. However, this did involve giving up the certainties of mathematical argumentation and learning to live with the uncertainties of induction. Economists need to do the same — abandon current methodology borrowed from science and develop a new methodology suited for the study of human beings and societies.

Asad Zaman

Models and laws in economics

Great lecture on how to do — and not to do — economics, delivered by Robert Skidelsky.

Fighting neoliberalism with Keynes and Minsky

Why economists understand less today than they did a century ago

Frank Hahn on the value of equilibrium economics

It cannot be denied that there is something scandalous in the spectacle of so many people refining the analyses of economic states which they give no reason to suppose will ever, or have ever, come about. It probably is also dangerous. Equilibrium economics … is easily convertible into an apologia for existing economic arrangements and it is frequently so converted.

Frank Hahn

On the irrelevance of mainstream economics

There is something about the way mainstream economists construct their models nowadays that obviously doesn’t sit right.

One might have hoped that humbled by the manifest failure of its theoretical pretences during the latest economic-financial crises, the one-sided, almost religious, insistence on axiomatic-deductivist modelling as the only scientific activity worthy of pursuing in economics would give way to methodological pluralism based on ontological considerations rather than formalistic tractability. But — empirical evidence still only plays a minor role in mainstream economic theory, where models largely function as a substitute for empirical evidence.

The dominant ideology in the economics academy, I am maintaining, is precisely the extraordinarily wide-spread and long-lasting belief that mathematical modelling is somehow neutral at the level of content or form, but an essential method for science, underpinning any proper or serious economics …

The scandal of modern economics is not that it gets so many things wrong, but that it is so largely irrelevant. However in being irrelevant … the mainstream modelling orientation cannot but serve to deflect criticism from the nature of status quo at the level of the economy and thereby work to sustain it … In truth, few people take any mainstream analysis seriously, except in economics faculties’ promotion exercises.

If macroeconomic models — no matter of what ilk — build on microfoundational assumptions of representative actors, rational expectations, market clearing, and equilibrium, and we know that real people and markets cannot be expected to obey these assumptions, the warrants for supposing that conclusions or hypotheses of causally relevant mechanisms or regularities can be bridged, are obviously non-justifiable. Incompatibility between actual behaviour and the behaviour in macroeconomic models building on representative actors and rational expectations microfoundations is not a symptom of ‘irrationality.’ It rather shows the futility of trying to represent real-world target systems with models flagrantly at odds with reality.

A gadget is just a gadget – and no matter how many brilliantly silly mathematical models you come up with, they do not help us working with the fundamental issues of modern economies. The mainstream economics project is — mostly because of its irrelevance — seriously harmful to most people, but also seriously harmless for those who benefit from the present status quo of our societies.

Ekonomi – vetenskap eller gissningslek?

Är nationalekonomi vetenskapligt baserad kunskap? Kan man förutspå hur enskilda individer eller hela samhällen kommer att agera ekonomiskt? Till exempel om miljonbonusar gör toppchefer mer lojala mot de företag som anställt dom? Kan ekonomiska analytiker verkligen se in i framtiden och förutspå kommande kriser? Eller handlar ekonomernas prognoser mer om en kvalificerad gissningslek?

Yours truly, Tore Ellingsen, och Daniel Waldenström ger sina svar i det här avsnittet av P1:s Vetandets värld.

Economics — where does it lead us?

The issue of interpreting economic theory is, in my opinion, the most serious problem now facing economic theorists. The feeling among many of us can be summarized as follows. Economic theory should deal with the real world. It is not a branch of abstract mathematics even though it utilizes mathematical tools. Since it is about the real world, people expect the theory to prove useful in achieving practical goals. But economic theory has not delivered the goods. Predictions from economic theory are not nearly as accurate as those offered by the natural sciences, and the link between economic theory and practical problems … is tenuous at best. Economic theory lacks a consensus as to its purpose and interpretation. Again and again, we find ourselves asking the question “where does it lead?”

Ariel Rubinstein