Compute the Pearson correlation coefficient r between two variables, given the covariance value between the two variables, and each variable's standard deviation. Correlation coefficients are often very useful for understanding and comparing the relationships among variables in an analytics study.
Compute the covariance value between two variables, given the Pearson correlation coefficient for the two variables, and each variable's standard deviation. Covariances reveal the extent to which the values of two variables change together, which is often very useful to know when examining the relationships among variables in an analytics study.