Big — and not so big — ideas in macroeconomics

9 Nov, 2017 at 22:44 | Posted in Economics | 1 Comment

In Athreya’s world, and that of a large part of the academic macroeconomics profession, macroeconomics does indeed begin with Walras, and the first modern development in the field was the formalization of Walras’ model by the economic theorists Arrow, Debreu and MacKenzie in the 1950s. The big subsequent development is the integration of growth theory into the static ADM framework to generate the modern dynamic stochastic general equilibrium (DSGE) models. Keynes’ 1936 ‘essay’ is treated as a curiosity, too vague and wordy to permit any real analysis.

This has the odd effect that many of the leading Keynesians of the postwar era … are given respectful cites for their work on growth theory, even as … their macroeconomic work is dismissed as being too silly even to be refuted … Real macro (that is, Walrasian GE applied to issues like the business cycle) begins, in this analysis, with Robert Lucas in the late 1970s.

All this gives me a bit more insight into the apparent convergence in macroeconomics in the early years of this century, and its breakdown in 2008. The New Keynesians understood themselves as having met their New Classical colleagues halfway, with DSGE models which were Keynesian in character, at least in the short run, while meeting the demands for rigorous microeconomic foundations. Meanwhile, the New Classical school were quietly snickering whenever Keynes’ name was mentioned, but were prepared to concede the possible existence of largely unspecified market “imperfections”, whose only role in practice was to justify a policy of inflation targeting.

The crisis that erupted in 2008 destroyed this spurious consensus. On any kind of Keynesian view, New or Old, the combination of high unemployment and zero interest rates implied that the economy had been driven into a Keynesian liquidity trap, with a need for fiscal stimulus on a massive scale. By contrast, for the New Classicals, a disaster of this kind could only be the result of government failure (or, in places where they still mattered, the pernicious actions of trade unions). Since this was implausible, New Classical economists have generally preferred to reassert dogma without too much attention to facts.

Broadly speaking, as far as academic macroeconomics is concerned, DSGE has won the day, not so much by force of argument as by maintaining control of the criteria for publication of journal articles in the field: it’s OK to assume full employment, and ignore inflation, but not to omit rigorous microfoundations for your model …

The result is that there is almost zero intersection between Big Ideas in Macroeconomics and what I would think of as macroeconomics. It’s not so much that I think Athreya is wrong is that we are talking past each other. As Charles Goodhart said of DSGE, Athreya’s version of macro excludes everything in which I am interested.

John Quiggin