But the overfit model scores those extra points in essence by cheating—by fitting noise rather than signal. It actually does a much worse job of explaining the real world.58 As obvious as this might seem when explained in this way, many forecasters completely ignore this problem. The wide array of statistical methods available to researchers enables them to be no less fanciful—and no more scientific—than a child finding animal patterns in clouds.* “With four parameters I can fit an elephant,” the mathematician John von Neumann once said of this problem.59 “And with five I can make him wiggle
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