Skip to main content

Game Theory, Equilibrium Theory, and Complexity

Image result for brian arthur economist

"In general equilibrium analysis, agents do not interact with one another directly, but only through impersonal markets. By contrast, in game theory all players interact with all other players, with outcomes specified by the game's payoff matrix."

Brian Arthur et al aren't so much contrasting game theory against GE analysis here, although that is what it sounds like. Rather they are saying that GE and GT have something in common, and they propose a model of economics, "complexity," that moves away from that commonality.

The quote comes from a introduction to a volume published in 1997 by the Santé Fe Institute, and as Arthur later wrote it was "as close as out economics program ... came to a manifesto."

The commonality is that interaction structures in both of the older theories are simple and extreme, either one-with-all or all-with-all.  In complexity, agents are chunked, so some interact more with their neighbors than with distant parties, and interact with distant parties only indirectly through the chunking.

That, BTW, is Brian Arthur's photo above.

Comments

Popular posts from this blog

A Story About Coleridge

This is a quote from a memoir by Dorothy Wordsworth, reflecting on a trip she took with two famous poets, her brother, William Wordsworth, and their similarly gifted companion, Samuel Taylor Coleridge.   We sat upon a bench, placed for the sake of one of these views, whence we looked down upon the waterfall, and over the open country ... A lady and gentleman, more expeditious tourists than ourselves, came to the spot; they left us at the seat, and we found them again at another station above the Falls. Coleridge, who is always good-natured enough to enter into conversation with anybody whom he meets in his way, began to talk with the gentleman, who observed that it was a majestic waterfall. Coleridge was delighted with the accuracy of the epithet, particularly as he had been settling in his own mind the precise meaning of the words grand, majestic, sublime, etc., and had discussed the subject with William at some length the day before. “Yes, sir,” says Coleridge, “it is a maj...

Searle: The Chinese Room

John Searle has become the object of accusations of improper conduct. These accusations even have some people in the world of academic philosophy saying that instructors in that world should try to avoid teaching Searle's views. That is an odd contention, and has given rise to heated exchanges in certain corners of the blogosphere.  At Leiter Reports, I encountered a comment from someone describing himself as "grad student drop out." GSDO said: " This is a side question (and not at all an attempt to answer the question BL posed): How important is John Searle's work? Are people still working on speech act theory or is that just another dead end in the history of 20th century philosophy? My impression is that his reputation is somewhat inflated from all of his speaking engagements and NYRoB reviews. The Chinese room argument is a classic, but is there much more to his work than that?" I took it upon myself to answer that on LR. But here I'll tak...

Recent Controversies Involving Nassim Taleb, Part I

I've written about Nassim Taleb on earlier occasions in this blog. I'll let you do the search yourself, dear reader, for the full background. The short answer to the question "who is Taleb?" is this: he is a 57 year old man born in Lebanon, educated in France, who has been both a hedge fund manager and a derivatives trader. He retired from active participation from the financial world sometime between 2004 and 2006, and has been a full-time writer and provocateur ever since. Taleb's writings for the general public began where one might expect -- in the field where he had made his money -- and he explained certain financial issues to a broad audiences in a very dramatic non-technical way. Since then, he has widened has fields of study, writing about just about everything, applying the intellectual tools he honed in that earlier work. As you might have gather from the above, I respect Taleb, though I have sometimes been critical of him when my own writing ab...