Question
What are the requirements for an experiment to be able to show that changes in one variable cause changes in another?
short answer
In order for an experiment to show that changes in one variable cause changes in another, the following requirements must be met:
1. Controlled variables: All other variables, aside from the independent and dependent variables being studied, must be controlled and kept constant.
2. Random assignment: Participants must be randomly assigned to different groups to ensure that any differences observed are due to the manipulation of the independent variable.
3. Manipulation of the independent variable: The independent variable must be intentionally manipulated in order to observe the effects on the dependent variable.
4. Replication: The experiment should be able to be repeated by other researchers in order to verify the results and ensure their reliability.
5. Causal relationship: The results of the experiment should show a clear and direct relationship between the independent and dependent variables, indicating that changes in one indeed cause changes in the other.