摘要: $$Cov(x,y)=\frac{\sum_{i=1}^{n}({x_i-\bar{x})^2}*\sum_{i=1}^{n}({y_i-\bar{y})^2}}{\sqrt{\sum_{i=1}^{n}({x_i-\bar{x})^2}}*\sqrt{\sum_{i=1}^{n}({y_i-\ba 阅读全文
posted @ 2020-10-11 14:45 jory_boke 阅读(2579) 评论(0) 推荐(0)