How are variables controlled in a controlled experiment?

Variables are controlled in a controlled experiment by manipulating and keeping them constant.

In a controlled experiment, variables are manipulated and kept constant to ensure that any observed changes are due to the manipulated variable and not any other extraneous factors. This is achieved by controlling the independent variable, which is the variable being manipulated, and keeping all other variables constant.

To control variables, researchers use a variety of techniques such as random assignment to groups, matching participants on relevant variables, and using standardised procedures. For example, in a study investigating the effects of caffeine on memory, researchers may randomly assign participants to either a caffeine or no caffeine condition, match participants on age and gender, and use the same memory test for all participants.

Controlling variables is important because it allows researchers to draw valid conclusions about the relationship between variables. Without controlling for extraneous variables, it is difficult to determine whether any observed effects are due to the manipulated variable or other factors.

In conclusion, controlling variables is a crucial aspect of conducting a controlled experiment. By manipulating and keeping variables constant, researchers can draw valid conclusions about the relationship between variables and avoid confounding variables that may affect the results.