Against The Odds: Preschoolers, Like Adults, Predict Outcomes That Are Desirable But Unlikely

Adults’ expectations are often biased by their desires, a phenomenon known as the desirability bias. The current study was the first to investigate the desirability bias in 4- and 5-year-old children and adults. Participants predicted whether a critical card would be drawn from decks containing 10 cards. Decks contained one of five different ratios of critical to noncritical cards (1:9, 4:6, 5:5, 6:4, 9:1). For some decks, drawing a critical card resulted in gaining a reward and in other decks, it resulted in a loss. Results showed that children, like adults, exhibited a desirability bias by predicting critical cards more often when they were associated with a gain than when they were associated with a loss. Furthermore, children showed a stronger desirability bias than adults for both gains and losses. Children, but not adults, showed a desirability bias for potential losses. Adults tended to use a strategy that minimized losses by predicting an undesirable outcome to occur when there was a potential loss at stake. Future research should attempt to measure the desirability bias in infants, as well as older adults, in order to better understand the developmental trajectory of the bias throughout the lifespan.