You will have little difficulty identifying the independent and dependent variables in an experiment if you take the time to think about what the experimenter did. Ask yourself the following questions: What did the experimenter manipulate? Is this the independent variable? Suppose we are designing an experiment to test our own hypothesis. How will we identify the independent and dependent variables? Because the experiment has not been done, we cannot examine the procedures that were used. There is no simple rule for deciding which variable is the independent variable in a hypothesis. To make this determination, we must think about the hypothesis and how we would go about testing it.