Evaluation of a multiple-stimulus presentation format for assessing reinforcer preferences.

We compared three methods for presenting stimuli during reinforcer-preference assessments: a paired-stimulus format (PS), a multiple-stimulus format in which selections were made with replacement (MSW), and a multiple-stimulus format in which selections were made without replacement (MSWO). Results obtained for 7 participants showed moderate to high rank-order correlations between the MSWO and PS procedures and a similar number of identified reinforcers. In addition, the time to administer the MSWO procedure was comparable to that required for the MSW method and less than half that required to administer the PS procedure. Subsequent tests of reinforcement effects revealed that some stimuli selected in the PS and MSWO procedures, but not selected in the MSW procedure, functioned as reinforcers for arbitrary responses. These preliminary results suggest that the multiple-stimulus procedure without replacement may share the respective advantages of the other methods.