出典:Wikipedia
出典:『Wikipedia』 (2011/06/25 23:51 UTC 版)
The observer-expectancy effect (also called the experimenter-expectancy effect, observer effect, or experimenter effect) is a form of reactivity, in which a researcher's cognitive bias causes them to unconsciously influence the participants of an experiment. It is a significant threat to a study's internal validity, and is therefore typically controlled using a double-blind experimental design.