CONCEPTS
HOME
             Independent Variable and Dependent Variable

      What is an independent variable?   What is a dependent variable? It is important to compare independent vs. dependent variables.  The independent variable and dependent varaible are two different types of variables in an experiment

Independent Variable Definition
     

       What is an independent variable?  The independent variable is the variable that is
manipulated by the researcher.  The independent variable is something that is hypothesized to influence the dependent variable.  The researcher determines for the participant what level or condition of the independent variable that the participant in the experiment receives.  For example, each participant in the experiment may be randomly assigned to either an experimental condition or the control condition.

Dependent Variable Definition

      What is a dependent variable?  The dependent variable is the variable that is simply
measured by the researcher.  It is the variable that reflects the influence of the independent variable.  For example, the dependent variable would be the variable that is influenced by being randomly assigned to either an experimental condition or a control condition.   

Examples of Independent Variable and Examples of Dependent Variable

      
In order to clarify the concepts of independent variable and dependent variable, it is important to provide examples.
       Imagine that you wished to know whether listening to music would increase productivity in the workplace.  You randomly assign each participant in this experiment to either an experimental condition or a control condition.  In the experimental condition, participants listen to music while they work.  In the control condition, the participants do not listen to music while they work.  In this example, listening to music vs. not listening to music is the independent variable.  The dependent variable in this example is productivity.
      Now imagine you wish to know whether a one-page or two-page resume is more persuasive.  You randomly assign each participant to read a one-page or two-page resume, and then they make a judgment about whether the person should be hired for a job.  In this example, the independent variable is the one-page vs. two-page resume.  The dependent variable in this example is the hiring judgment.