Monday, February 26, 2007

Runway Quants in the Vortex: Useless Math


Or, How you gonna keep them down on the farm after they see the bare shoulders of those seductive quantitative models?

The ships was free of bounds, it was true. But it had entered a phantasm allegorical.
The compass needles spinning in overdrive, as the calendar pages sucked into the vortex. And the models began to spit out gibberish. Yet a lazy air conditioned mid-ought porch somehow came to mind.


Spent a couple of evenings at Dr. Shroud’s home on a visit in the mid oughts. Piled high were scientific journals, to be tossed about, launched hazhapardly in the air, and ingested like artsy scientific popcorn, I guess. There was that and true fiddle faddle too, and the tube was always on. The mags were fodder for grand illuminations in underneath the Shroud’s bald cranium.

The covers of the journals - I hadn’t really sat down with these types of publications for some ten years before - were surprising - very vivid, imagistic, literally abstract, because the computer model had come recently into being big time. The data was increasingly being modeled and visualized. Big rolls of colored toilet paper unflapping. Ordinate Mounds of pudding interspersed with graphs of cherries and whip cream. Topological candy, psychedelic morphing. All representing black holes in conjuration, populations in migration, penicillin reactions in Tibetans, and thangs. All bringing interesting visualizations of phenomena. Ones a good science head could nog on and, oh, I don’t know, maybe edge closer to cure for cancer.

Nay, colonel, you are jumping back when you should be jumping ahead.

Yes, true, in fact I am.

The model. You first hold it up and you are wary. Then it becomes familiar, and you believe it more than a fair representation. Like anything, the model can be mishandled The glue gets to you. It provides a warmth. Although it is just a theory, it starts to look better than the real thing. Even better if it’s a good theory; less better if not. Which brings us to the object of today’s post: Useless Arithmetic. A topic dear to the heart of many a school boy. The notion of Useless Arthmetic authored by Orin Pilkey and Linda Pilkey-Jarvis.

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The notion of Useless Arthmetic is appealing. The models must make assumptions. As we move up the scale, as the systems become more complex, it is likely the assumptions will begin to overcome the outcome. Last straws and such. Theory has its limits in the real world. Thes notion is bopped about in the new book Useless Arithmetic.

The notion of Useless Arthmetic is appealing. But it does arrive during an important effort to move global warming from the debating society stage to the lets do something about it society stage.

Note the authors do see a problem with their assertion: One is climate change, in which, they say, experts' justifiable caution about model uncertainties can encourage them to ignore accumulating evidence, and so on. The shoe is usually on the other foot ["Remember when the facts dont fit the model, the facts got to change."]

As I looked closer at the blog trail of useless math tears it appeared authors were not entirely opposed to modeling, but were concerned that it is being overused and under-understood. The publisher has up some comments too. These are pr comments. Abuzz. "The book offers fascinating case studies depicting how the seductiveness of quantitative models has led to unmanageable nuclear waste disposal practices, poisoned mining sites, unjustifiable faith in predicted sea level rise ... " Oh those seductive quantitative models, they broke up many a happy home.

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The Problems in Modeling Nature, With Its Unruly Natural Tendencies - New York Times
http://www.nytimes.com/2007/02/20/science/20book.html
Useless Arithmetic; Why Environmental Scientists Can't Predict the Future
http://www.columbia.edu/cu/cup/catalog/data/023113/0231132123.HTM
Places and Spaces: Useless Arithmetic
http://epd372.blogspot.com/2007/02/useless-arithmetic.html
USELESS ARITHMETIC - Daily Policy Digest NCPA
http://www.ncpa.org/sub/dpd/index.php?page=article&Article_ID=14220
Under the Covers: Useless arithmetic? - Gristmill: The environmental news blog
http://gristmill.grist.org/story/2007/2/21/124321/594

Note.. .The American Scientist has about the best treatment here, but that article is only open to subscribers. Maybe I can summ it later...

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