Experimenter bias refers to the iInfluence of the experimenter''s expectations or personal beliefs on the findings of a study. Experimenter bias is a type of artifact and threatens bo
th internal and external validity.
Moreover. Experimenter bias is confounding variable that occurs when an experimenter unintentionally encourages participants to respond in a way that supports the hypothesis; the
the effect that an experimenter may unknowingly exert on results of an experiment, usually in a direction favoring the experimenter's hypothesis