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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 independent variable is the variable that the researcher manipulates in the experiment. This variable will then be hypothesized in order to influence the dependent variable. The independent variable has a big effect on the entire experiment, and is very important in drawing the conclusion of the experiment.