experimenter effects definition
(psychol) the influence of an experimenter's expectations on his results. experimenter effect in Medicine. experimenter effect n. The influence of the experimenter's behavior, personality traits, or expectancies on the results of his or her own research.
Observer Expectancy Effect. The observer expectancy effect, also called the experimenter expectancy effect, is a phenomenon that can occur when a researcherâs 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.