名詞 covariance:

1. (statistics) the mean value of the product of the deviations of two variates from their respective means

co.var.i.ance

n.（名詞）
A statistical measure of the variance of two random variables that are observed or measured in the same mean time period. This measure is equal to the product of the deviations of corresponding values of the two variables for their respective means.
協(xié)方差：在觀察或測(cè)量同一平均時(shí)間的兩個(gè)任意變量的變化的一個(gè)統(tǒng)計(jì)值。這個(gè)值等于這兩變量的各自平均值偏離其相應(yīng)值的乘積