Dr. Nancy wants to understand the effect of exercise on self-reported levels of depression. She assigns participants to either a group that exercises 30 minutes each day or a group that does not exercise at all. She then records the depression level of her participants after a period of time. In this example, exercise would be the and level of depression would be the .

independent variable; dependent variable

Explanation:

An independent variable is the variable that causes an effect, or that is manipulated in order to ascertain the effects it has on a dependent variable.

On the other hand, a dependent variable is the effect caused by the independent variable, which is tested or measured. The dependent variable is dependent on the independent variable.  

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