Correlation A Magnitude or Power quantity?

1. Does correlation capture magnitude?
2. What does correlation measure?
3. Does correlation have units?
4. How is correlation calculated?

Does correlation capture magnitude?

Correlations range in magnitude from -1.00 to 1.00. The larger the absolute value of the coefficient (the size of the number without regard to the sign) the greater the magnitude of the relationship.

What does correlation measure?

Correlation is a measure of association that tests whether a relationship exists between two variables. It indicates both the strength of the association and its direction (direct or inverse). The Pearson product-moment correlation coefficient, written as r, can describe a linear relationship between two variables.

Does correlation have units?

The correlation coefficient does not have any units.

It's just a number.

How is correlation calculated?

The correlation coefficient is calculated by determining the covariance of the variables and dividing that number by the product of those variables' standard deviations.