【单选题】Let S be the covariance matrix associated with the random vector . S have eigenvalue-eigenvector pairs , be the ith sample principal components. then the sample covariance of and = ( )
【简答题】Complete the sentences with the correct form of the expressions below. assert oneself be associated with major in make sense stand for 1 I ___________ politics and economi...
【判断题】Given below is the scatter plot of the market value (thousands$) and profit (thousands$) of 50 U.S. companies. Higher market values appear to be associated with higher profits.