A contingent or dependent variable is a factor in an experiment or study that changes in response to other variables. It relies on the influence of independent variables, which are manipulated to observe their effect. For example, in a study examining the impact of study time on test scores, the test scores are the contingent variable, as they depend on the amount of study time. In research, understanding contingent variables is crucial for establishing cause-and-effect relationships. By identifying how these variables respond to changes, researchers can draw meaningful conclusions and make informed decisions based on their findings.