Definitions must first be laid out in order to classify the variables in question as dependent, independent, moderating, extraneous, or intervening. The dependent variable refers to the variable that is being tested in a scientific experiment. Dependent variables are dependent upon and obtain their value from independent variables. During an experiment, the experimenter changes the independent variable. When the independent variable is changed, the change in the dependent variable is observed and recorded. Thus, the dependent and independent variable are related. The dependent variable is the variable that is being measured. Therefore, in this experiment, the dependent variable is sales. The independent variable refers to the variable that is manipulated or controlled in the experiment. The independent variables have an affect on the dependent variable and are viewed as causes witch affect other variables. Therefore, in this experiment, the independent variable is per capita income.