After controlling for Z,the partial correlation coefficient is .78.The bivariate Pearson's r between X and Y was only .51.Which interpretation is consistent with these results?
A)None,these results are mathematically impossible.
B)There is a spurious relationship between X and Y.
C)X and Z are both caused by Y.
D)X and Z are separate,uncorrelated causes of Y.

Question

Quizplus · Accepted Answer

The partial correlation coefficient of .78 between X and Y after controlling for Z implies that the relationship between X and Y is stronger than the bivariate Pearson's correlation of .51. This suggests that Z is acting as a confounding variable, and that X and Z are separate, uncorrelated causes of Y. Therefore, the best choice is D.

After Controlling for Z,the Partial Correlation Coefficient Is