Dr. Fantino will carry out experiments to investigate choice behavior. All are relevant to his delay-reduction theory of choice, which states that performance for a stimulus may be predicted most accurately by calculating the reduction in the length of time to reinforcement correlated with the onset of the stimulus in question relative to the length of time to reinforcement measured from the onset of the trial. In other words, the greater the improvement in terms of temporal proximity or waiting time to reinforcement, correlated with the onset of a stimulus, the more preferred that stimulus will be. The experiments are to assess potentially important modifications of this theory. For example, it has never been ascertained whether the effectiveness of a stimulus in delay-reduction terms is predicted most accurately by calculating the reduction in the time to reinforcement measured from the onset of the preceding stimulus or by calculating the reduction in the time to reinforcement measured relative to the average time to primary reinforcement in the situation. These experiments will assess those questions which are central to an appreciation of response strength. The second set of experiments will explore the adequacy of delay-reduction in accounting for choice in situations where the theory predicts nonoptimal behavior. The third set of experiments includes a novel extension of the theory to conditional discrimination problems, in which Dr. Fantino will asses the effectiveness of two conflicting sources of information on choice. This section also should help illuminate the factors governing base-rate errors reported in judgment tasks. Topics such as reinforcement and choice--including nonoptimal decision- making--have relevance for health concerns.
