APA Dictionary of Psychology

in parapsychology experiments, the finding that a participant’s “calls,” or guesses, are more accurate for one set of targets in an experiment (e.g., die faces with high values, Zener cards with stars) than for another (e.g., die faces with low values, Zener cards with crosses) or even for one type of testing condition over another when the experiments ostensibly test the same preternatural ability. See also decline effect; differential effect; focusing effect; position effect; sheep–goat effect.