Using Progressive Ratio Schedules as a Means of Evaluating Absolute and Relative Reinforcer Value

We evaluated behavior exhibited by 3 individuals with developmental disabilities using progressive ratio schedules. High- and low-preferred stimuli (i.e., edibles) were determined based on the results of a paired-stimulus preference assessment (Fisher et al., 1992) and were evaluated in subsequent reinforcer and progressive ratio assessments using a modified reversal design. Data were collected on responding to arbitrary tasks associated with high- and low-preferred edibles under concurrent and single operant schedules of presentation. Results showed that for two of three participants, stimuli determined to be low-preferred via a preference assessment functioned as reinforcers when evaluated independently of high-preferred stimuli and under gradually increasing response requirements. The results suggest that for cases in which a high-preferred stimulus is unavailable or unfeasible, the contingent delivery of relatively less-preferred stimuli may maintain appropriate behavior, even as response effort is increased. In addition, results of the progressive ratio evaluation are suggestive of stimulus value