There is a correlation between depression and memory: more frequently depressed people often have worse memory than less frequently depressed people. Genetics, however, may have an effect on a study participant's depression and memory. This is known as:
A) selection bias
B) the experimenter expectancy effect
C) the directionality problem
D) the third variable problem

Question

Quizplus · Accepted Answer

The third variable problem refers to a situation in which a correlation between two variables is actually caused by a third variable. In this case, genetics could be the third variable causing both depression and memory issues, meaning that the correlation between the two is not necessarily indicative of a causal relationship between the two variables.

There Is a Correlation Between Depression and Memory: More Frequently