If you have profit sharing in a firm or profit sharing in homework assignment, or any joint projects, you have to worry about too little effort being contributed because there's an externality.

如果你是一个公司的股东,或者和别人一起做作业及其他合作项目,你们需要注意到因为外部性,实际上每个人都付出了较少的努力

耶鲁公开课 - 博弈论课程节选

because it gets you used to living with other people and you know, cooperating.

因为你就习惯了和别人住，与人合作。

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So, for example, if you have a joint project that you're working on, perhaps it's a homework assignment, or perhaps it's a video project like these guys, that can turn into a Prisoners' Dilemma.

比如说你和别人要进行一个合作项目,可能是家庭作业,或者像他们正在进行的视频采集项目,它能变成一个囚徒困境

耶鲁公开课 - 博弈论课程节选