Ben Recht is looking for problems. He develops mathematical strategies to help researchers, from urban planners to online retailers, cut through blizzards of data to find what they're after.

He resists the "needle in the haystack" metaphor because, he says, the researchers, engineers, and business people he has worked with usually don't know enough about their data to reach their goal.

"My work tries to incorporate as much expert knowledge as possible into data analysis," says Recht. "Once you codify this expertise, the needle often turns out to be a pitchfork."

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