So right footed players find it easier to shoot to the left as facing, to shoot across the goal.

习惯用右脚射门的球员从左路进攻,会更容易把球射入球门

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The goal keeper is standing at the goal.

对方门将站在球门线上

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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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