In one study they looked at a housing project in Manhattan and they asked people where their best friend was and 90% of them said, "My best friend is in the same building as me," and 50% of them says the same floor.

在一个针对一栋曼哈顿住宅的研究中,他们问住户他们最好的朋友住在哪,90%的人说，“我最好的朋友和我住同一栋楼”,50%说住在同一层楼。

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