In the largest analysis of the issue thus far, investigators have found that the smaller the research team working on a problem, the more likely it was to generate innovative solutions. . . . .
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“You might ask what is large, and what is small,” said Dr. Evans. “Well, the answer is that this relationship holds no matter where you cut the number: between one person and two, between ten and twenty, between 25 and 26.”
It also holds within every field in science, whether physics, psychology, computer science, mathematics, or zoology, he added: “You see it within field, within topics. And two-thirds of the effect we found is within the individual. That means that if I’m writing a paper, and I partner with one other person, or two, the result is less disruptive with each person I add.”Can Big Science Be Too Big?
How much of this is about social norms and regression to the mean? Add enough people and pretty soon you get an average.