In research design, what distinguishes an experiment from a correlational study?

In research design, what distinguishes an experiment from a correlational study?

• A. An experiment manipulates an independent variable
• B. A correlational study proves causation
• C. An experiment uses only descriptive statistics
• D. A correlational study uses random assignment

Answer: (A)

The key idea is that experiments involve actively changing one variable to see its effect on another. By manipulating the independent variable and often using random assignment to create comparable groups, researchers can control for other factors and observe causal effects on the dependent variable. Correlational studies, on the other hand, simply observe variables as they occur naturally and examine relationships without manipulation, so they can reveal associations but not causation. That’s why manipulating the independent variable is the defining feature that distinguishes an experiment from a correlational study.

The key idea is that experiments involve actively changing one variable to see its effect on another. By manipulating the independent variable and often using random assignment to create comparable groups, researchers can control for other factors and observe causal effects on the dependent variable. Correlational studies, on the other hand, simply observe variables as they occur naturally and examine relationships without manipulation, so they can reveal associations but not causation. That’s why manipulating the independent variable is the defining feature that distinguishes an experiment from a correlational study.