Book review: Everything has a hidden explanation

Which is more dangerous, a gun or a swimming pool? Why do drug dealers live with their moms? What impact did Roe v. Wade have on violent crime? How do parents of different races or classes name their children?

Chances are you've never thought to ask yourself these questions. Chances are, however, you're curious as to what the answers to them are. This constant challenging of popular thinking lies at the heart of a fascinating (and unfortunately titled) new book called Freakonomics:A Rogue Economist Explores the Hidden Side of Everything.

Steven D. Levitt, a recipient of the prestigious John Bates Medal (given every two years to the most accomplished economist less than 40 years old) got some help in writing from journalist friend Stephen J. Dubner, a writer for The New Yorker. Together, they've crafted an intriguing, highly original little book.

"The conventional wisdom is often wrong," writes Levitt. "Crime didn't keep soaring in the 1990s, money alone doesn't win elections, and - surprise - drinking eight glasses of water a day has never actually been shown to do a thing for your health."

Without a doubt, the most provocative section of the book deals with abortion and the falling crime rate in the 1990s. All kinds of theories are put forth for the decline - community policing, stricter gun control laws, and a better economy, among others - but Levitt determined that these had at best a minimal effect. Other factors, like the hiring of more police officers and stricter sentencing guidelines had an effect, but did not solely account for the drop.

The Supreme Court decision Roe v. Wade legalized abortion in 1973. Levitt points out that with abortion legally accessible, it would be a poor, single mother who would be most likely to take advantage of it. "These two factors - childhood poverty and a single-parent household - are among the strongest predictors that a child will have a criminal future." In the 1990s, the first generation of children born after Roe was hitting its late teens, when young men enter their criminal prime.

Levitt notes that in states that legalized abortion earlier, like New York and California, the crime rate dropped earlier. Lest he be accused of advocating this as a crime-fighting tool, he offers an economist's cost-benefit analysis. Say that one newborn is worth 100 fetuses. By doing the math, the number of prevented murders wouldn't justify the number of abortions. Thus, "even for someone who considers a fetus to be worth only one one-hundredth of a human being, the trade-off between higher abortions and lower crime is, by an economist's reckoning, terribly inefficient."

Levitt engages in similar myth-busting when examining the finances of a drug dealing Chicago gang. A graduate student, Sudhir Venkatesh, spent considerable time with the gang in an attempt to study its culture. He gained its trust to the point where one dealer, who served as the gang's financial chief, gave Venkatesh four years worth of the gang's financial records.

By analyzing this treasure trove of information, Levitt draws some startling conclusions. Contrary to popular myth, most of the gang members weren't rolling in the cash. The leader was making about $100,000 annually, but the minions were earning a mere $3.30 an hour - less than they would make starting off at McDonald's. What's more, one in four gang members died in the period being analyzed. Most death row inmates have a better chance of survival.

Freakonomics is filled with these sorts of insights, and Levitt delivers them in rapid fire succession. Interspersed in between are plenty of bits of trivia to keep your interest.

There are some weird elements to this book. For instance, each chapter opens with a passage from an admiring New York Times Magazine profile that Dubner wrote of Levitt. Some readers may also be put off by the book's boast that it has "no unifying theme." But these are small prices to pay for a work as unique as Freakonomics.

And just in case you're still wondering, a child is 100 times more likely to die by drowning in a swimming pool than as a result of gunplay.