8. Control Variables

Control variables are independent variables, but they are not the independent variables of main interest. We need to account for them, that is, control for them in order to understand the main independent variable of concern. Control variables remain important, which is whey we need to account for them. For instance, if I wanted to understand the impact of ethnic identity on a person's voting preferences, then I would probably want to control for a person's level of education and level of income because those two factors may also affect the person's voting preferences.