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Freakonomics. Steven Levitt is a "genius" who can "take a seemingly meaningless set of numbers, ferret out the telltale pattern and recognize what it means," writes Steven E. Landsburg in The Wall Street Journal.
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" The Levitt treatment, as Steven Landsburg describes it, is based on "the identification of a suspicious pattern, a labyrinth of reasoning to rule out the innocent explanations and a compelling indictment." The results can be quite astonishing -- perhaps most of all Levitt's evidence that "legalized abortion was the single biggest factor in bringing the crime wave of the 1980s to a screeching halt."
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Levitt started with the observation "that crime began falling nationwide just 18 years after the Supreme Court effectively legalized abortion. He was struck by the fact that in five states crime began falling three years earlier than it did everywhere else. These were exactly the five states that had legalized abortion three years before Roe v. Wade." Levitt doesn't necessarily conclude that crime fell "because hundreds of thousands of prospective criminals had been aborted," but he "piles pattern on pattern until the evidence overwhelms you ... He doesn't pretend to settle the matter, but in just a few pages he constructs exactly the right framework for thinking about it and then leaves the reader to draw his (or her) own conclusions.