Question

Linear Correlation In this section we use r to denote the value of the linear correlation coefficient. Why do we refer to this correlation coefficient as being linear?

Short answer

The term “linear” is used to describe the correlation coefficient because the correlation coefficient represented by r can be used to assess the straight-line pattern between the two variables on a scatterplot.

Step-by-step solution

Given information

It is known that r is used to represent the linear correlation coefficient between two variables.

Linearity property of correlation coefficient

The term linear refers to the straight-line pattern in general. On a scatter plot, if the sample values describe any approximate straight-line pattern, then measure r (linear correlation coefficient) can be used for the statistical measurement of strength and direction.

In other words, the term “linear” is used to denote the correlation coefficient (r) between two variables becauseit quantifies the straight-line pattern between the two quantitative variables.

As a result, a straight-line relationship is used to define r; linear correlation coefficient.