title: Probability matching: encouraging optimal responding in humans.
abstract: Two hundred undergraduate students participated in a repeated-trials binary choice procedure in which choice of one outcome was correct on 75% of trials. Subjects received 192 trials and were divided into five conditions: (1) control; (2) subjects were given the actual probabilities; (3) subjects were told if they did well they could leave early; (4) competition condition; (5) midway through the task subjects were asked to recommend a strategy for another subject. Half of the subjects in each group were told that the best they could do was to be correct on 75% of the trials. This manipulation permitted assessment of the hypothesis that subjects in probability-matching tasks are seeking a strategy that will be correct on 100% of the trials. The results partially confirmed this hypothesis. In addition, two of the variables improved performance significantly (giving probabilities and asking subjects to recommend a strategy). However, while subjects in all groups improved significantly over trials, optimal choice did not occur in this task.
authors.affiliation: Department of Psychology-0109, University of California, San Diego, La Jolla, CA 92093-0109, USA. efantino@ucsd.edu
authors.forename: Edmund
authors.initials: E
authors.lastname: Fantino
authors.forename: Ali
authors.initials: A
authors.lastname: Esfandiari
mesh_terms: D000328:Adult; D001288:Attention; D003163:Competitive Behavior; D005260:Female; D006801:Humans; D008297:Male; D009042:Motivation; D011337:Probability Learning; D011597:Psychomotor Performance