For a certain data set the regression equation is y = 2 + 3x.The correlation coefficient between y and x in this data set ___.
A)must be 0
B)is negative
C)must be 1
D)is positive
E)must be 3

Question

Quizplus · Accepted Answer

The correlation coefficient (r) measures the strength and direction of the linear relationship between two variables. It ranges from -1 to 1, with negative values indicating a negative relationship and positive values indicating a positive relationship. Since the regression equation has a positive slope of 3, it suggests that there is a positive relationship between y and x. Therefore, the correlation coefficient must also be positive. Choice D is the best choice that reflects this relationship.

For a Certain Data Set the Regression Equation Is Y