Retrodiction (or postdiction, though this should not be confused with the use of the term in criticisms of parapsychological research) is the act of making a prediction about the past. This is especially useful when one wishes to test a theory whose actual predictions are too long-term to be of immediate use. The theory is used to manipulate data concerning the more distant past in order to predict an event in the less distant past. This is useful in, for example, the fields of archaeology, evolutionary biology, forensic science, and cosmology.