Decisive: How to Make Better Choices in Life and Work

by Chip Heath

Almost certainly, you’d read more of the positive reviews. You really want this restaurant to be great. A recent meta-analysis of the psychology literature illustrated how dramatic this effect is. In reviewing more than 91 studies of over 8,000 participants, the researchers concluded that we are more than twice as likely to favor confirming information than disconfirming information. (So, scientifically speaking, you’d probably read twice as many four-star reviews as two-star reviews.) The meta-study found that the confirmation bias was stronger in emotion-laden domains such as religion or politics and also when people had a strong underlying motive to believe one way or the other (as in Upton Sinclair’s observation, “It is difficult to get a man to understand something when his salary depends on his not understanding it!”). The confirmation bias also increased when people had previously invested a lot of time or effort in a given issue.