In statistics, a response variable is the quantity that is being studied based on a number of factors, which are measured as explanatory variables. This is similar to the use of the dependent and independent variable classification.

A response variable is classified as a dependent variable. An explanatory variable may be compared to an independent variable. For example, a study is done to determine if the number of hours spent doing homework has an effect on the grade a student earns on an exam. Since the value of one variable changes the value of another, there exists a response variable and an explanatory variable. The number of hours studied is classified as the explanatory variable, and the score on the test is the response variable.