measurement of correlation meaning in English

Beta is a measurement of correlation between the price fluctuations of individual security ( or portfolio ) and the average price fluctuations of all securities in the market , that is called " systematic risk coefficient " . beta has not only important implications in finance theory , but also widely used in investment practices such as asset pricing , portfolio management and performance valuation
一方面,系数是正确理解资本市场理论中有关收益?风险关系的关键参数,系数的稳定与否对于capm模型在投资决策方面的应用如资产定价、股票收益预测和投资绩效评价至关重要;另一方面,资本市场上的许多事件研究也都依赖于系数的稳定性。