FEEDBACK AND RESPONSE MODE IN PERFORMING A BAYESIAN DECISION TASK

In a complex decision-making situation 64 male undergraduates received data generated by 1 of 3 hypotheses according to specified conditional probabilities. Ss inferred which hypothesis had generated the data or estimated the probability of each hypothesis given the data. Feedback was given after each trial either as the hypothesis which generated the data or the probability that each hypothesis generated the data calculated by Bayes' theorem. The percentage of trials when Ss chose the most probable hypothesis was significantly higher for the groups responding with a single hypothesis than for the probability response groups, and higher for the Bayesian probability feedback groups than for the groups receiving no feedback. The Bayesian probability feedback group also gave probability responses which were much closer to the optimal probabilities than did the no-feedback group. (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.