Final answer:
A control group is an untreated group in a randomized experiment that receives an inactive treatment to provide a baseline for comparison with the experimental group. This allows researchers to determine if changes in the experimental group result from the independent variable rather than other factors or chance.
Step-by-step explanation:
A control group is an untreated group of individuals or subjects that serves as a benchmark in a randomized experiment. This group is managed exactly like the experimental group, except for the fact that they do not receive the active treatment or experimental manipulation. For example, to test a new educational method's effectiveness, the control group would receive standard teaching, while the experimental group would receive the new method. Then, both groups' performances could be compared to assess the method's impact. By having a control group, researchers can determine if it's truly the independent variable causing an observed effect and not other variables or chance.
The control group helps researchers to maintain the integrity of the experiment by providing a baseline to compare against the experimental groups, allowing for a clearer understanding of the independent variable's effects. It is important to note that control groups help in minimizing experimental errors and biases like the placebo effect or experimenter bias. Therefore, each experiment must have a control group to ensure valid and reliable results.