The differential outcomes effect refers to the increase in accuracy obtained in discrimination tasks when rewards provided for correct responses vary according to the stimulus presented. The present research examined this effect in a sample of 63 university students (18-38 yrs old) discriminating multiple stimuli. A computer task was used to teach the meanings of 15 Japanese kanji characters, with both immediate (photos) and backup (lottery prizes) rewards following correct responses. Students were randomly allocated to one of three conditions: a differential condition (photos and prizes were uniquely associated with specific kanji), a partial differential condition (photos but not prizes were uniquely associated with specific kanji), and a nondifferential condition (photos and prizes were randomly associated with specific kanji). Participants in the differential condition learned the kanji meanings more quickly than those in the nondifferential condition. Accuracy in the partial differential condition was intermediate to, and not significantly different from, the other two conditions. These results extend the generality of the differential outcomes effect and have important practical implications.
Miller, Odette T.; Waugh, Kevin M.; and Chambers, Karen
"Differential Outcomes Effect: Increased Accuracy in Adults Learning Kanji with Stimulus Specific Rewards,"
The Psychological Record:
3, Article 5.
Available at: http://opensiuc.lib.siu.edu/tpr/vol52/iss3/5