Far from having a disruptive effect the presence of outsiders or people who don't fit in with the rest of the group can actually have a beneficial effect on productivity. Researchers at Brigham Young University in the U.S. conducted a traditional group problem-solving exercise but added a newcomer to the group after they had been working for five minutes. When the newcomer was a social outsider the teams were more likely to solve the problem successfully. The newcomers in the experiment didn't necessarily ask tougher questions, have more up-to-date information or argue their point of view better but when existing group members sided with them the 'insiders' felt obliged to justify their decision and this improved the quality of the debate. Although the groups where the newcomer was more familiar felt they had performed better they actually performed worse than the groups where the newcomer was more socially distinct.
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