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Use of Differential Decision Criteria for Preferred and Nonpreferred Conclusions

Filed in Research News
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Today’s highlight article comes from Dan Gilbert’s mention of it in his recent New York Times Op-Ed piece:

“Two psychologists, Peter Ditto and David Lopez, told subjects that they were being tested for a dangerous enzyme deficiency. Subjects placed a drop of saliva on a test strip and waited to see if it turned green. Some subjects were told that the strip would turn green if they had the deficiency, and others were told that the strip would turn green if they did not. In fact, the strip was just an ordinary piece of paper that never changed color.

So how long did subjects stare at the strip before accepting its conclusion? Those who were hoping to see the strip turn green waited a lot longer than those who were hoping not to. Good news may travel slowly, but people are willing to wait for it to arrive.

The same researchers asked subjects to evaluate a student’s intelligence by examining information about him one piece at a time. The information was quite damning, and subjects were told they could stop examining it as soon as they’d reached a firm conclusion. Results showed that when subjects liked the student they were evaluating, they turned over one card after another, searching for the one piece of information that might allow them to say something nice about him. But when they disliked the student, they turned over a few cards, shrugged and called it a day.”

For over a quarter century we’ve known that people use heuristics to make decisions. The challenge of the next quarter century is to figure out what governs which heuristics are pulled from the toolbox when. When do we choose between a heuristic that cuts search short and one that digs through information? These kinds of considerations, and not fat (as in overweighted) linear models, are a start.

Reference: Motivated Skepticism: Use of Differential Decision Criteria for Preferred and Nonpreferred Conclusions. Peter H. Ditto and David F. Lopez. Journal of Personality and Social Psychology 1992, Vol. 63, No. 4, 568-584.