## Alan Kirman debunking mainstream economics

19 Jul, 2021 at 15:36 | Posted in Economics | 1 Comment.

An economic theory that does not go beyond proving theorems and conditional ‘if-then’ statements — and do not make assertions and put forward hypotheses about real-world individuals and institutions — is of little consequence for anyone wanting to use theories to better understand, explain or predict real-world phenomena.

Building theories and models on patently ridiculous assumptions we know people never conform to, does not deliver real science. Real and reasonable people have no reason to believe in ‘as-if’ models of ‘rational’ robot-imitations acting and deciding in a Walt Disney-world characterised by ‘common knowledge,’ ‘full information,’ ‘rational expectations,’ zero transaction costs, given stochastic probability distributions, risk-reduced genuine uncertainty, and other laughable nonsense assumptions of the same ilk. Science fiction is not science.

For decades now, economics students have been complaining about the way economics is taught. Their complaints are justified. Force-feeding young and open-minded people with unverified and useless autistic mainstream theories and models cannot be the right way to develop a relevant and realist economic science.

Much work done in mainstream theoretical economics is devoid of any explanatory interest. And not only that. Seen from a strictly scientific point of view, it has no value at all. It is a waste of time. And as so many have been experiencing in modern times of austerity policies and market fundamentalism — a very *harmful* waste of time.

Alan Kirman presents a forceful critique of mainstream economics in general, and more specifically, of the kind of assumptions that mainstream macroeconomic DSGE modelling (New Classical, ‘New Keynesian’, RBC, etc.) is built on. For most heterodox critics of mainstream economics the themes are probably well-known. That said, let me just give some brief comments on what Kirman at the end of the interview presents as an alternative to mainstream orthodoxy — agent-based modelling.

Agent-based models are formal models usually constructed using mathematical programming and performing simulations and ‘artificial experiments’ with the intention of being able to (more explicitly than in conventional mainstream game theory) describe aggregate effects and dynamics of interacting individuals and socio-economic structures without standardly having to assume equilibria, non-emergence, Walrasian auctioneers, representative agents, rational expectations, etc., etc..

Agent-based models come in different degrees of realism and are usually conceptualised as different kinds of self-organising complex systems. But one thing they all have in common is reliance on mathematical formalism. In essence the agent-based modelling endeavour in macroeconomics is an attempt at providing new alternative mathematical models where many of the bizarre and ridiculous known-to-be ‘unrealistic’ assumptions in standard DSGE models are replaced with other less ‘unrealistic’ assumptions. But the idea that mathematical modelling as such is always appropriate to apply is never seriously questioned. And that’s where I find it hard to follow. One set of mathematical tractability assumptions are substituted for another. But what if the mathematical modelling *in itself* is the problem? What if the use of mathematical-formalistic modelling *in itself* biases your research efforts in specific directions? If it is the mathematical-formalistic approach *in itself* that is the problem, we only end up with different models based on the same unquestioned mathematical modelling strategy. From my own critical realist perspective I can’t see that mathematical modelling is the self-evidently appropriate way to perform analyses of societies and economies. The kind of ‘closures’ demanded of the target systems for warranting the analyses, I would argue, simply often aren’t there.

As a critique of mainstream economics, yours truly fully appreciates the work done by people like Alan Kirman. But although their alternative agent-based models in many ways are superior to the more traditional mainstream ‘Walt Disney’ kind of models, I am not convinced that their unquestioned attachment to mathematical-formalist modelling is the right way to move forward in making economics a more realist and relevant science.

## 1 Comment »

RSS feed for comments on this post. TrackBack URI

### Leave a Reply

Blog at WordPress.com.

Entries and Comments feeds.

Aren’t interlocking balance sheets a better way to model economies?

And when you actually look at balance sheets, can’t you find a lot of emergence ($8 trillion in a decade on the Fed’s bs alone)?

Can’t you basically get to the same place (lots of money creation) using ridiculous DSGE model assumptions if you properly scale the size of the financial sector? Do some recent BIS DSGE models come to right conclusions because they can model the Fed’s reaction function? Do they perhaps do this by simply exempting the Fed from rational expectations? (Or they redefine rationality for a central bank?)

Comment by rsm— 20 Jul, 2021 #