The Terms
Extraneous variables, control group, counterbalancing
Extraneous variable
Extraneous variables are any variables that you are not intentionally studying in your experiment or test. When you run an experiment, you’re looking to see if one variable (the independent variable) has an effect on another variable (the dependent variable).Other variables, perhaps ones that never crossed your mind, might influence the outcome of an experiment. These variables are called extraneous variables.
Control group
The control group is defined as the group in an experiment or study that does not receive treatment by the researchers and is then used as a benchmark to measure how the other tested subjects do. For example, in an experiment in which blood pressure medication is tested, one group is given the blood pressure medication while the control group is given a placebo pill instead.
Counterbalancing
Counterbalancing is a technique used to deal with order effects when using a repeated measures design. With counterbalancing, the participant sample is divided in half, with one half completing the two conditions in one order and the other half completing the conditions in the reverse order. It is a technique in experimental design that is used to avoid the confounding variables.