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Observer Expectancy Effect. The observer expectancy effect, also called the experimenter expectancy effect, is a phenomenon that can occur when a researcherâs beliefs or expectations cause him or her to unconsciously influence the participants of an experiment. In order to conserve the internal validity of an experiment, researchers can use a double-blind experimental design.
The factor that is changed or controlled in an experiment is called the independent variable. An experimenter makes alterations to the independent variable in order to test the effects these changes have on the dependent variable. Continue Reading