What does Pearson's correlation primarily measure?

Pearson's correlation primarily measures the linear relationship and strength between two quantitative variables. It provides a numerical value, typically between -1 and 1, representing how closely the two variables tend to move together. A value close to 1 indicates a strong positive linear relationship, while a value close to -1 indicates a strong negative linear relationship. A result close to 0 suggests that there is little to no linear correlation between the variables.

This measure is specifically designed for quantitative data and assumes that the relationship being measured can be approximated linearly, making it an effective tool in statistical analysis for assessing the degree to which two variables are related.