How does a researcher ensure the validity of an experiment?

The validity of an experiment is fundamentally about ensuring that the observed effects are genuinely representative of the phenomena being studied and not due to confounding factors or biases. Controlling variables is key to this process, as it involves identifying and managing extraneous variables that could influence the results. This means that the researcher manipulates the independent variable while keeping other conditions constant, which helps isolate the effects of that variable on the dependent variable.

Using appropriate methodologies is equally crucial, as it encompasses the design of the experiment, selection of measurement tools, and procedures that align with the research question. By employing standardized methods, researchers can reliably replicate the study and enhance the credibility of their findings.

While randomizing the sample population is beneficial for generalizing results and minimizing bias, it should be complemented by strict control of variables to ensure that the experiment's conditions remain consistent. Overall, combining variable control with sound methodological practices fosters robust experimental validity.