Prior probability information and changes in event frequency in three-choice learning.

Abstract

In probabilistic situations known to be static, short-term alterations in event frequencies should have progressively less effect upon subjective probability as the number of trials increases. Assuming that expectation for a static environment would increase with increasing amount of prior information about the event probabilities, the amount of prior information and the location of alterations in event frequency were varied in a three-choice probability learning task. Both variables had large effects upon the observed choice patterns and, in general, the greater the amount of prior information, the less sensitive was choice behavior to changes in event frequency during later trials.