In this case, we must state what we mean by the terms “media violence” and “aggression” as we will study them. Operational variables (or operationalizing definitions) refer to how you will define and measure a specific variable as it is used in your study.įor example, if we are concerned with the effect of media violence on aggression, then we need to be very clear what we mean by the different terms. Time of day has a significant effect on alertness. Stressful experiences significantly increase the likelihood of headaches.Ĥ. Social class has a significant effect on IQ scores.ĭV.…ģ. Lack of sleep significantly affects learning in 10-year-old boys. In this particular example the type of information is the independent variable (because it changes) and the amount of information remembered is the dependent variable (because this is being measured).įor the following hypotheses name the IV and the DV. organized or random) given to participants to see what effect this might have on the amount of information remembered. In an experiment, the researcher is looking for the possible effect on the dependent variable that might be caused by changing the independent variable.Įxamples of Independent and Dependent Variables in Experimentsįor example, we might change the type of information (e.g. An example of a dependent variable is depression symptoms, which depends on the independent variable (type of therapy). The dependent variable is the variable being tested and measured in an experiment, and is 'dependent' on the independent variable. Variable is the only important difference between the experimental (e.g. In a well-designed experimental study, the independent For example, allocating participants to either drug or placebo conditions (independent variable) in order to measure any changes in the intensity of their anxiety (dependent variable). The independent variable is the variable the experimenter manipulates or changes, and is assumed to have a direct effect on the dependent variable. One is called the dependent variable and the other the independent variable.
Variables are given a special name that only applies to experimental investigations. What are Independent and Dependent Variables?