Independent variable is a term in mathematics. In the mathematical equation y=f(x), x is an independent variable, which refers to the amount manipulated and changed by researchers. There are four independent variables, namely stimulus characteristic independent variable, environmental characteristic independent variable, subject characteristic independent variable and temporary difference between subjects.

Brief introduction of dependent variable

Dependent variable is a term in mathematics, which belongs to proper nouns in functions. In the functional relationship, the value of the dependent variable will change with the change of the independent variable. For example, in y=f(x), y is the dependent variable.