In research terminology, what does the term 'manipulation' refer to?

The term 'manipulation' in research terminology specifically refers to the process of controlling and altering independent variables to observe their effects on dependent variables in experimental research. This is a crucial aspect of hypothesis testing, where researchers aim to determine cause-and-effect relationships. By manipulating certain variables in a controlled setting, researchers can isolate the effects of these variables and draw more accurate conclusions about their interactions and impacts.

In this context, manipulation is essential for establishing validity in experimental design, allowing researchers to make definitive statements about how changing one variable influences another. This contrasts with simply recording outcomes or observing external factors, which do not involve the active control over variables needed to determine causal relationships.