Khan Academy Static

An experiment assigns some subjects to receive a treatment while others don't get the treatment. Experiments also try to control for other variables so we can see if there's a cause-effect relationship between the treatment and some response. Learn more about the differences between observational studies and experiments in this tutorial.

4536_Correlation_and_causality.html

4537_Types_of_statistical_studies.html

4538_Appropriate_statistical_study_example.html