Independent variable

Definition

An independent variable is a factor that is manipulated or controlled in an experiment to observe its effect on the dependent variable. It is the presumed cause in a cause-and-effect relationship.

5 Must Know Facts For Your Next Test

1. Independent variables are chosen by the researcher and are not affected by other variables in the experiment.
2. In experimental design, changing the independent variable helps determine if it has a causal effect on the dependent variable.
3. There can be more than one independent variable in an experiment, but each should be clearly defined and isolated.
4. Random assignment of subjects to different levels of the independent variable helps ensure unbiased results.
5. Identifying and correctly manipulating the independent variable is crucial for maintaining internal validity in an experiment.

Review Questions

• What role does the independent variable play in an experimental design?
• Why is random assignment important when dealing with independent variables?
• How can having multiple independent variables affect an experiment?

Related terms

Dependent Variable: The outcome or response measured to see if it is influenced by changes in the independent variable.

Control Variable: A factor that is kept constant to prevent it from influencing the outcome of an experiment.

Random Assignment: The process of assigning subjects to different treatment groups using randomization to eliminate bias.