An experimenter gives one group of depressed subjects a certain amount of the medication Prozac and another group of depressed subjects a comparatively higher dose. Then she measures the number of violent or suicidal thoughts members of both groups have. In this situation, the independent variable is
A) the measure of medication administered.
B) the initial level of depression of the subjects.
C) the number of violent thoughts the subjects report.
D) the number of suicidal thoughts the subjects report.

Question

Quizplus · Accepted Answer

The independent variable is the medication administered, as it is being manipulated by the experimenter to see its effect on the dependent variable (number of violent or suicidal thoughts reported). The initial level of depression of the subjects is a potential confounding variable that should be controlled for in the study, but it is not the independent variable being manipulated. The number of violent and suicidal thoughts reported are the dependent variables being measured, not the independent variable.

An Experimenter Gives One Group of Depressed Subjects a Certain