Tuesday, May 21, 2013

The Self-Organizing Economy

Krugman, Paul. (1996). The Self-Organizing Economy. Cambridge, MA: Blackwell.

The concept of self-organization is difficult (for me) to get a grasp on, so I turned to this well-known writer who tackled economics. What I like about him is that he's always conversational in tone, and I have to be the same way, because I'm explaining language to people who already know quite a bit, but don't know self-organization. But second, he actually went as far as to work out the math; this I admire him for, and don't know if I can do the same for language.

Now it's time to return the book to the library (though I could just renew it); I've had it for months, and I need to mine it for quotes and get it out of here. I'm sure somebody else could use it!

He points out that scientists of complexity theory have not had much luck with economics and economists, because:
the authors of articles and books on complexity almost never talk to serious economists or read what serious economists write; as a result, claims about the applicability of the new ideas to economics are usually coupled with statements about how economies work (and what economists know) that are so ill-informed as to make any economist who happens to encounter them dismiss the whole enterprise. (p. 2)
His definition of a self-organizing system is the following:
...what links the study of embryos and hurricanes, of magnetic materials and collections of neurons,is that they are all self-organizing systems: systems that, even when they start from an almost homogeneous or almost random state, spontaneously form large-scale patterns. (p. 3)
Self-organization is not always good:
...self-organization is not necessarily, or even presumptively, a good thing. I think it is fair to accuse many of the writers on complexity, especially but not only the more popular ones, of falling into this fallacy...Self organization is something we observe and try to understand, not necessarily something we want. (p. 6)
This part is about Schelling and his model of how neighborhoods become segregated:
Thus Schelling derived, without any fanfare, a theme of many writers on complexity: local, short-range interactions can create large-scale structure. (p. 17)
About the field of complexity in general:
...the whole rationale of the field is the idea that common principles may apply to subjects with very different details....(p. 29)
His main thesis is that economics is a self-organizing system in two senses that are shown by complexity theorists to be properties of self-organizing systems. First is that:
starting from disordered initial conditions they tend to move to highly ordered behavior, and at least in a statistical sense this behavior exhibits surprisingly simple regularities...(p. 36)
The second sense is that they create order from random growth. (p. 37). Of this he tells a story:
Take a ceramic object, say a Grecian urn, and throw it hard against a stone wall, so that it shatters randomly into innumerable pieces. Surely such an act can do nothing but create disorder! And yet (so The Economist tells us) a strange hidden order emerges. Carefully gather up the pieces larger than 0.1 grams, the number larger than 0.01 grams, and so on, and you will find something remarkable: the pieces will obey a power law. And not just any power law: if it really was a Grecian urn, the exponent will take on a particular value; if it was a ceramic sphere it will take on another value; and so on. That is, a seemingly disorderly and complex process of fragmentation (which is random growth with a minus sign) produces the simple order of a power law, and the exponent of that power law contains important information - in this case, incredibly, it turns out to reveal the shape of the original object. (p. 49)
Here is a complexity theory bibliography:
Bak, P. (1991). Self-organizing criticality, Scientific American (January).
Kauffman, S. (1993). The Origins of Order. New York: Oxford Univ. Press.
Lewin, R. (1992). Complexity: Life at the Edge of Chaos. New York: Macmillan.
Nicolis, G. and Prigogine, I. (1989). Exploring Complexity. New York: W.H. Freeman.
Schelling, T. (1978). Micromotives and Macrobehavior. New York: W.W. Norton.
Waldrop, W. M. (1993). Complexity. New York: Basic Books.

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