Economics, 3rd Edition

People are Reluctant to Change Their Minds

People tend to interpret evidence to confirm beliefs they already hold. In one study, subjects were asked 

to read and evaluate a research report on whether capital punishment deters crime. After reading the 

report, those who initially favoured the death penalty said they were surer in their view, and those who 

initially opposed the death penalty also said they were surer in their view. The two groups interpreted the 

same evidence in exactly opposite ways.