说明：  最小二乘法是一种数学优化技术。它通过最小化误差的平方寻找数据的最佳函数匹配，最小二乘法还可用于曲线拟合。
(Least squares is a mathematical optimization technique. It finds the best function match of the data by minimizing the square of the error, and the least square method can also be used for curve fitting.)