Correlation Coefficient

The correlation coefficient, typically denoted r measures how strongly two numerical variables are linked to each other. The following is the formula for r, with a brief description of the variables:

• The number of data points is given by n.
• The capital sigma denotes addition of several terms.
• The data points are represented by xi and yi.
• The mean of the xi is denoted by x with a horizonatal bar over it.
• The standard deviation of the xi is denoted by sx.
• The mean of the yi is denoted by y with a horizonatal bar over it.
• The standard deviation of the yi is denoted by sy.