"Correlation coefficient is to analyze the linkage relationship between the performance of two different securities from the perspective of asset return correlation. The absolute value of the correlation coefficient reflects the strength of the correlation between the returns of the two securities. The correlation coefficient can measure the changing relationship between any two asset returns. "

Securities are all kinds of economic rights and interests certificates, and also refer to specialized products. It is a legal document used to prove that the holder enjoys certain rights. Mainly including capital security, currency securities and commodity securities. In a narrow sense, securities mainly refer to securities products in the securities market, including property market products such as stocks, debt market products such as bonds, and derivative market products such as stock futures, options and interest rate futures.