Now picture two candidates, one intrinsically appealing and the other not so. The appealing candidate raises much more money and wins easily. But was it the money that won him the votes, or was it his appeal that won the votes and the money?

That's a crucial question but a very hard one to answer. Voter appeal, after all, isn't easy to quantify. How can it be measured?

It can't, really -- except in one special case. The key is to measure a candidate against ... himself. That is, Candidate A today is likely to be similar to Candidate A two or four years hence. The same could be said for Candidate B. If only Candidate A ran against Candidate B in two consecutive elections but in each case spent different amounts of money. Then, with the candidates' appeal more or less constant, we could measure the money's impact.

As it turns out, the same two candidates run against each other in consecutive elections all the time indeed, in nearly a thousand U.S. congressional races since 1972. What do the numbers have to say about such cases?

Here's the surprise: the amount of money spent by the candidates hardly matters at all. A winning candidate can cut his spending in half and lose only 1 percent of the vote. Meanwhile, a losing candidate who doubles his spending can expect to shift the vote in his favor by only that same 1 percent. What really matters for a political candidate is not how much you spend; what matters is who you are. (The same could be said and will be said, in chapter 5 about parents.) Some politicians are inherently attractive to voters and others simply aren't, and no amount of money can do much about it. (Messrs. Dean, Forbes, Huffington, and Golisano already know this, of course.)

And what about the other half of the election truism -- that the amount of money spent on campaign finance is obscenely huge? In a typical election period that includes campaigns for the presidency the Senate, and the House of Representatives, about $1 billion is spent per year -- which sounds like a lot of money, unless you care to measure it against something seemingly less important than democratic elections.

It is the same amount, for instance, that Americans spend every year on chewing gum.


This isn't a book about the cost of chewing gum versus campaign spending per se, or about disingenuous real-estate agents, or the impact of legalized abortion on crime. It will certainly address these scenarios and dozens more, from the art of parenting to the mechanics of cheating, from the inner workings of the Ku Klux Klan to racial discrimination on The Weakest Link. What this book is about is stripping a layer or two from the surface of modern life and seeing what is happening underneath. We will ask a lot of questions, some frivolous and some about life and death issues. The answers may often seem odd but, after the fact, also rather obvious. We will seek out these answers in the data -- whether those data come in the form of schoolchildren's test scores or New York City's crime statistics or a crack dealer's financial records. (Often we will take advantage of data that were incidentally left behind, like an airplane's sharp contrail in a high sky.) It is well and good to opine or theorize about a subject, as humankind is wont to do, but when moral posturing is replaced by an honest assessment of the data, most subjects actually become even more compelling.

Morality, it could be argued, represents the way that people would like the world to work whereas economics represents how it actually does work. Economics is above all a science of measurement. It comprises an extraordinarily powerful and flexible set of tools that can reliably assess a thicket of information to determine the effect of any one factor, or even the whole effect. That's what "the economy" is, after all: a thicket of information about jobs and real estate and banking and investment. But the tools of economics can be just as easily applied to subjects that are more -- well, more interesting.

The foregoing is excerpted from Freakonomics by Steven D. Levitt and Stephen J. Dubner. All rights reserved. No part of this book may be used or reproduced without written permission from HarperCollins Publishers, 10 East 53rd Street, New York, NY 10022