Although groups brainstorm less effectively than individuals, they perform better on certain judgment tasks, perhaps because members learn from each other.
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Asked to estimate the flight distance between European cities, groups of students averaged 30% fewer errors than individuals, according to a team led by Thomas Schultze of Georg-August-University in Goettingen, Germany. Accuracy can be further increased if members are told which member is most competent, the researchers say.
[Source: HBR]