So strategy ?i is a best response to the strategy S-i of the other players if my payoff from choosing ?i against S-i, is weakly bigger than that from choosing Si' against S- i, and this better hold for all possible other strategies I could choose.

策略?i是其他参与人策略S-i的,最佳对策,如果此时我选?i的收益,弱优于此情况下选Si'的收益,这对于所有我可以选择的策略都成立

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