Correlation Coefficient

Correlation measures the strength and direction of the linear relationship between two variables.

The formula for the correlation coefficient (Pearson’s r) is:

$r = \frac{\sum (x_i – \bar{x})(y_i – \bar{y})}{\sqrt{\sum (x_i – \bar{x})^2 \sum (y_i – \bar{y})^2}}$

Where:

• $(x_i)$ and $(y_i)$ are the individual sample points.
• $(\bar{x})$ and $(\bar{y})$ are the means of the (x) and (y) samples, respectively.