没有参与这项研究的宾夕法尼亚大学心理学家尼娜·施特罗明格指出，她希望这种影响是真实的，但不能排除一些未知的混杂变量。

Psychologist Nina Strohminger at the University of Pennsylvania, who was not involved in the study, says she wants the effect to be real but cannot rule out some unknown confounding variable.

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对局外人来说，这种商业模式是否可靠还是未知之数，在被问及是否已经向其他国家或公司作出要出租太空站空间的承诺时，毕格罗也拒绝提供答案。

The soundness of the business case is unknown to outsiders. Mr. Bigelow declines to say if he has firm commitments from any countries or companies to rent space on his space stations.

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曾经也踢过足球并当过足球教练的金斯伯格说，这类的科学研究能做的也就只能到这了，比赛中存在着太多的因素影响，而这些也将永远是比赛中未知的变数。

"This kind of science can only take you so far," said Ginsburg, who has also played and coached soccer. "There are an enormous number of factors that go into this."

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