The manipulated or independent variable is the variable that is intentionally changed or manipulated by the researcher in an experiment to see its effect on the responding or dependent variable. The controlled variable, on the other hand, is the variable that is kept constant throughout the experiment to ensure that it does not interfere with the relationship between the manipulated and responding variables. The responding or dependent variable is the variable that is measured or observed to determine the effect of the manipulated variable. It changes in response to the changes in the manipulated variable.
