Independent and dependent variables are key concepts in experimental research. The independent variable is the variable that is manipulated or varied by the researcher, and presumed to cause changes in the dependent variable. The dependent variable is the response or outcome that is measured and presumed to be affected by changes in the independent variable. Examples given include a study of participation in an intensive study program as the independent variable affecting graduation rates as the dependent variable, and a study of knowledge, attitudes, and conflict handling skills as independent variables affecting commitment to remaining a resident assistant as the dependent variable.