Interpreting
Correlation Coefficients
Properties of the Linear Correlation Coefficient
- The correlation coefficient is a unitless measure.
- The value of r will always be between −1 and +1 inclusively. That is, \(-1\leq r\leq1\).
- If the values of \(x\) and \(y\) are interchanged, the value of r will be unchanged.
- If the values of \(x\) and/or \(y\) are converted to a different scale, the value of \(r\) will be unchanged.
- The value of \(r\) is sensitive to outliers and can change dramatically if they are present in the data.
.jpg "relationship meter")
*The range of the linear correlation coefficient is from −1 to +1. If there is a strong positive linear relationship between the variables, the value of r will be close to +1.*
* If there is a strong negative linear relationship between the variables, the value of r will be close to −1.*
*When there is no linear relationship between the variables or only a weak relationship, the value of r will be close to 0.*