08 November 2008

Stochastic

I first became acquainted with this word in my student days at Cal. I read Gregory Bateson's Mind and Nature, and Dr. Bateson spent a bit of time on "stochastic processes," dancing around in evolution, psychology, anthropology, and whatnot, trying to put together some sort of ecological treatise. I used to read stuff like that. Now I read Out of the Gutter.

Bateson threw around a number of big words, but he had the decency to include a glossary. Here's his take on stochastic:


Stochastic. (Greek, stochazein, to shoot with a bow at a target; that is, to scatter events in a partially random manner, some of which achieve a preferred outcome) If a sequence of events combines a random component with a selective process so that only certain outcomes of the random are allowed to endure, that sequence is said to be stochastic.
(p. 252 Bantam New Age 1980 paperback edition)

Wolfram MathWorld says the word is synonymous with "random," and Bartleby agrees with the etymology.

Years later I came across the notion of a "random walk." This was in
Burton Malkiel's A Random Walk Down Wall Street. I've read, at most, a handful of things about finance. This engaging book was the most memorable and enjoyable. I have the everyman's ignorance about these things, and like I said, spend my time reading noir. But I love words, and when I consulted my trusty Cartoon Guide to Statistics on the subject of "random walks," they had this to say:

Random walks begin with a coin flip. Suppose you move ahead one step for a head and back one step for a tail. Repeated flips produce a stochastic process called a random walk.

(Larry Gonick, empahsis mine)

There's that pesky Greek again! WordMan™ would love "stochastic." He'd whip it out in all sorts of verbal crises in his globe-trekking exploits. What could be more stochastic than world travel? And think of the other opportunities--dazzling
my baseball readers with erudite posts on the stochastic nature of our beloved pastime! Screw sabermetrics. Stochasto-ball is here.

This post does have a point. It isn't often that you get "stochastic" in an interview, much less twice. But my brother-in-law,
Bart Rothwell, is an awfully bright fellow, and knows all sorts of things about science, statistics, and finance. If anyone has the the intellectual street cred to toss it around, it's him. So I was reading about Bart's latest endeavor (way to go, Bart!), and there was "stochastic." Words are like a bottle of good whiskey--you get to uncork that bottle again and pour out another dram. Each time you get to experience another aspect of their complexity and richness. Damn! I'm thirsty!

1 comment:

nancyo said...

Lovely, wonderful riff on the richness of words! 'Stochastic':
a new dram for me. Grand.