He chose the line so that--this is Gauss-- he chose the line to minimize the sum of squared distances of the points from the lines.

高斯选的这条线,所有点距离这条直线的平方和,是所有直线中最小的

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Now there many ways I can connect these two points together. The simplest way is to draw a straight line. It's called the linear interpolation. My line is not so straight, right here. You could do a different kind of line.

最简单的办法是,像这样画一条直线,这叫线性插值,不过我的这条线画得不太直，你也可以用别的办法,比如一条抛物线。

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