The appropriate correlation coefficient for measuring the direction and strength of the linear relationship between two ranked or ordinal variables is ______.
A) the Spearman correlation coefficient
B) the point-biserial correlation coefficient
C) the phi correlation coefficient
D) none of these

Question

Quizplus · Accepted Answer

The Spearman correlation coefficient is the best choice for measuring the direction and strength of the linear relationship between two ranked or ordinal variables. It applies to variables that have a monotonic relationship, which means that as one variable increases, the other variable either increases or decreases consistently. The point-biserial correlation coefficient is appropriate for measuring the correlation between a binary variable and a continuous variable. The phi correlation coefficient is used to measure the association between two binary variables. Therefore, neither option B nor C is an appropriate choice for this scenario.

The Appropriate Correlation Coefficient for Measuring the Direction and Strength