The Signal and the Noise: Why So Many Predictions Fail-but Some Don't

by Nate Silver

The process of disentangling a financial crisis—everyone trying to figure out who owes what to whom—can produce hangovers that persist for a very long time. The economists Carmen Reinhart and Kenneth Rogoff, studying volumes of financial history for their book This Time Is Different: Eight Centuries of Financial Folly, found that financial crises typically produce rises in unemployment that persist for four to six years.86 Another study by Reinhart, which focused on more recent financial crises, found that ten of the last fifteen countries to endure one had never seen their unemployment rates recover to their precrisis levels.87 This stands in contrast to normal recessions, in which there is typically above-average growth in the year or so following the recession88 as the economy reverts to the mean, allowing employment to catch up quickly. Yet despite its importance, many economic models made no distinction between the financial system and other parts of the economy.