Psychology research indeed suggests that the more desirable a future event is, the more likely people think it is. When the sociologists Edward Brent and Donald Granberg studied wish fulfillment in U.S. presidential elections between 1952 and 1980, they found that 80 percent of each of the major candidates’ supporters expected their preferred candidate to win by a ratio of around four to one. “People distort their perception of an election’s closeness in ways that are consistent with their preferences,” a later paper concluded. Likewise, after the 2008 election, researchers analyzed survey predictions from 19,000 Americans and found that Democrats tended to think Barack Obama was more likely to win, while Republicans assumed John McCain would.

Conversely, the more someone dreads or fears a potential outcome, the less likely they think it is to happen. In November 2007, economists in the Philadelphia Federal Reserve’s Survey of Professional Forecasters predicted just a 20 percent chance of “negative growth”—read: decline—in the U.S. economy any time in 2008, despite visible signals of an impending recession. There is, the economist Sergey Smirnov wrote in a review of economists’ botched predictions on the 2008 recession, “some deep inherent unwillingness to predict undesirable things.”