We're going to be taking away from lucky-- you think of yourself as randomly on any point of this.

我们会从有钱人那里拿走一些,你可以想象自己作为例子

耶鲁公开课 - 金融市场课程节选

er is a vector at each point of length one pointing radially away from the center.

r 是一个模长恒为 1 的矢量,方向沿半径向外

耶鲁公开课 - 基础物理课程节选