What is the primary purpose of control variables in research?

The primary purpose of control variables in research is to account for other factors that may influence the dependent variable. When conducting a study, there are often multiple variables at play that can affect the outcome. By controlling for these additional variables, researchers can isolate the effect of the independent variable on the dependent variable, leading to more accurate and reliable results. This process helps to ensure that any observed relationships are not due to confounding factors but can be attributed to the variable of interest.

In contrast, while ignoring irrelevant factors might seem beneficial, it does not capture the essence of control variables, which actively manage and account for other influences. Reducing the number of observations needed is not a function of control variables; rather, the use of control variables may require maintaining a sufficient sample size to detect the desired effect reliably. Increasing sample size is sometimes necessary for statistical power but is not directly linked to the role of control variables in addressing confounding factors.