Which type of variable is manipulated in an experiment?

In an experiment, the independent variable is the type of variable that researchers manipulate to determine its effect on another variable. This manipulation allows scientists to observe the outcomes and establish cause-and-effect relationships. By changing the independent variable, researchers can measure the impact it has on the dependent variable, which is the outcome they are interested in studying.

In contrast, the dependent variable is what is measured in response to changes in the independent variable. Controlled variables are those factors that are kept constant throughout the experiment to ensure that the results are due only to the manipulation of the independent variable, not other influences. Confounding variables are external influences that could affect the results but are not controlled, potentially leading to misleading conclusions. Understanding these distinctions is crucial in experimental design, where the goal is to isolate the effects of the independent variable accurately.