So this line represents the expected payoff of shooting to the middle as a function of the probability that the goal keeper dives to the right.

这条线表示从中路射门时罚球者的收益,是门将扑向右路概率的一个函数

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So the payoff here is something like u1 if the goal keeper dives to the left is equal to 4, by which I mean there's a 40% chance of scoring.

收益u1表示门将扑向左路时,罚球者从左路进攻的收益是4,也就是说球被射入球门的概率是40%

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