two heads are better than one

Two Heads Are Not Always Better Than One

two heads full of  ideas

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From the corporate boardroom to the kitchen table, important decisions are often made in collaboration. But are two—or three or five—heads better than one? Not always, according to new research from the University of Pennsylvania’s Wharton School. “People who make judgments by working with someone else are more confident in those judgments. As a result they take less input from other people”—and this myopia wipes out any advantage a pair may have over an individual, says psychologist Julia A. Minson, who conducted the study with Jennifer S. Mueller. “The collaborative process itself is the problem.” The findings appear in the journal Psychological Science, published by the Association for Psychological Science.

To test the hypothesis that confidence born of collaboration takes a toll on the quality of judgment, Minson and Mueller asked 252 people to estimate nine quantities related to U.S. geography, demographics, and commerce, either individually or in pairs after discussion. They were then offered the estimates of other individuals and pairs and allowed to revise their own; the final estimates therefore could come from the efforts of two to four people. To sweeten the pot, participants earned a $30 bonus for each of two estimation rounds, but lost $1 for each percentage point their answer deviated from correct. Individuals also rated their confidence in their judgments. [continue reading…]