来自《耶鲁大学开放课程：博弈论 第9集 第9集》

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  we've been using now for several weeks,
  其实是一样的
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  except everywhere where before we saw a pure strategy,
  只不过我们之前讲的都是纯策略
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  which was an S, I have replaced it with a P.
  即S 而现在我换成了混合策略P
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  So the same definition except
  其实定义基本都是一样的
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  I'm using mixed strategies instead of pure strategies.
  只不过这里我用混合策略替代了纯策略
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  But an implication of our lesson is what?
  我们总结出的结论该怎么表示呢
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  It's that if Pi* is part of a Nash Equilibrium,
  如果Pi*是纳什均衡的一部分
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  so if Pi* is a best response to what everyone else is doing, P-i*,
  即Pi*是对P-i*的最佳对策
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  then each of the pure strategies involved in Pi*
  则Pi*中的每一个纯策略
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  must itself be a best response.
  其本身也一定是最佳对策
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  So an implication of the lesson is, the lesson implies the following.
  这个结论的含义就是
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  If Pi* of a particular strategy is positive,
  如果Pi*中某个纯策略被赋予正概率