shake that cat

It's hard to know where to start

Stephen J. Dubner and Steven D. Levitt's article in the June 5 New York Times Magazine, on economists doing research with monkeys, "Monkey Business," fits well into an issue otherwise full of hedge fund managers and Silicon Valley venture capitalists:

..."The capuchin has a small brain, and it's pretty much focused on food and sex," says Keith Chen, a Yale economist who, along with Laurie Santos, a psychologist, is exploiting these natural desires—well, the desire for food at least—to teach the capuchins to buy grapes, apples and Jell-O. "You should really think of a capuchin as a bottomless stomach of want," Chen says. "You can feed them marshmallows all day, they'll throw up and then come back for more."

...If, for instance, the price of Jell-O fell (two cubes instead of one per token), would the capuchin buy more Jell-O and fewer grapes? The capuchins responded rationally to tests like this—that is, they responded the way most readers of The Times would respond.

...The data generated by the capuchin monkeys, Chen says, "make them statistically indistinguishable from most stock-market investors."

...Once, a capuchin in the testing chamber picked up an entire tray of tokens, flung them into the main chamber and then scurried in after them—a combination jailbreak and bank heist—which led to a chaotic scene in which the human researchers had to rush into the main chamber and offer food bribes for the tokens, a reinforcement that in effect encouraged more stealing.

...The introduction of money was tricky enough; it wouldn't reflect well on anyone involved if the money turned the lab into a brothel. To this end, Chen has taken steps to ensure that future monkey sex at Yale occurs as nature intended it.

The undergraduate population will be glad to hear it.

[For video clips of the monkeys and a monkey cam, see the Freakonomics Web site.]