Quantity versus quality : the opportunity to choose back-up reinforcers in a token economy

Preference for single versus varied reinforcers was assessed in the context of a token system. This study also assessed the preferences of 4 participants for one stimulus versus a number of qualitatively different stimuli, presented contingent on academic task completion. A paired-choice preference assessment was conducted followed by a reinforcer assessment using a combined reversal and multi-element design. The purpose of these procedures was to determine whether higher rates of responding would occur during conditions in which token reinforcement produced access to back-up reinforcers compared to a no reinforcement condition. Next, the opportunity to choose single versus varied token reinforcers was presented in a concurrent -chains arrangement. The dependent variables were the number of letters traced per min and the number of tokens earned per min during 3-min sessions, and the percentage of selections for single versus varied conditions. Results showed that response rates during the reinforcer assessment were higher during the reinforcement condition relative to the no reinforcement condition. A preference was not detected for 2 of 4 participants when the opportunity to choose from the same or qualitatively different reinforcers was presented. One of 4 participants preferred selecting the varied-choice condition (i.e., qualitatively different back-up reinforcers), and a second participant showed a similar pattern, but results were inconclusive due to limited data