I need 25,000 square feet at least.

至少25000平方呎。

I want to connect to this definition of covariance to everything we've been doing with least squared regression.

将协方差这个定义与们用最二乘回归所做一切联系起来。

His profound contribution was the introduction of the method of " least squares, " a standard procedure in regression analysis used to minimize the sum of the square differences between observed and predicted data.

他贡献是引入了“最二乘法”，这是回归分析中一种标准程序，用于最化观测数据与预测数据之间平方差之和。